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Soil Survey of Rock Island County_ Illinois

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Soil Survey of Rock Island County_ Illinois Powered By Docstoc
					United States   In cooperation with Illinois
Department of
Agriculture
                Agricultural Experiment
                Station
                                               Soil Survey of
Natural
Resources
                                               Rock Island
Conservation
Service                                        County, Illinois
NRCS Accessibility Statement
        The Natural Resources Conservation Service (NRCS) is committed to making its
     information accessible to all of its customers and employees. If you are experiencing
     accessibility issues and need assistance, please contact our Helpdesk by phone at
     1-800-457-3642 or by e-mail at helpdesk@helpdesk.itc.nrcs.usda.gov. For assistance
     with publications that include maps, graphs, or similar forms of information, you may
     also wish to contact our State or local office. You can locate the correct office and
     phone number at http://offices.sc.egov.usda.gov/locator/app.
                                                                                                                   3




How To Use This Soil Survey
This publication consists of a manuscript and a set of soil maps. The information provided can be useful in planning
the use and management of small areas.

To find information about your area of interest, locate that area on the Index to Map Sheets. Note the number of
the map sheet, and turn to that sheet.

Locate your area of interest on the map sheet. Note the map unit symbols that are in that area. Turn to the
Numerical Index to Map Units, which lists the map units by symbol and name and shows the page where each
map unit is described. The map unit symbols and names also appear as bookmarks, which link directly to the
appropriate page in the publication.

The Contents shows which table has data on a specific land use for each soil map unit. Also see the Contents for
other sections of this publication that may address your specific needs.
4




        This soil survey is a publication of the National Cooperative Soil Survey, a joint effort
    of the United States Department of Agriculture and other Federal agencies, State
    agencies including the Agricultural Experiment Stations, and local agencies. The
    Natural Resources Conservation Service (formerly the Soil Conservation Service) has
    leadership for the Federal part of the National Cooperative Soil Survey.
        Major fieldwork for this soil survey was completed in 1998. Soil names and
    descriptions were approved in 1998. Unless otherwise indicated, statements in this
    publication refer to conditions in the survey area in 1998. This survey was made
    cooperatively by the Natural Resources Conservation Service and the Illinois
    Agricultural Experiment Station. It is part of the technical assistance furnished to the
    Rock Island County Soil and Water Conservation District. Financial assistance was
    provided by the Rock Island County Board and the Illinois Department of Agriculture.
        Soil maps in this survey may be copied without permission. Enlargement of these
    maps, however, could cause misunderstanding of the detail of mapping. If enlarged,
    maps do not show the small areas of contrasting soils that could have been shown at a
    larger scale.
        The United States Department of Agriculture (USDA) prohibits discrimination in all of
    its programs on the basis of race, color, national origin, gender, religion, age, disability,
    political beliefs, sexual orientation, and marital or family status. (Not all prohibited bases
    apply to all programs.) Persons with disabilities who require alternative means for
    communication of program information (Braille, large print, audiotape, etc.) should
    contact the USDA’s TARGET Center at 202-720-2600 (voice or TDD).
        To file a complaint of discrimination, write USDA, Director, Office of Civil Rights,
    Room 326W, Whitten Building, 14th and Independence Avenue SW, Washington, DC
    20250-9410, or call 202-720-5964 (voice or TDD). USDA is an equal opportunity
    provider and employer.


      Cover: A view from the loess hill bluffs overlooking the Mississippi River Valley.




        Additional information about the Nation’s natural resources is available on the
      Natural Resources Conservation Service homepage on the World Wide Web. The
      address is http://www.nrcs.usda.gov.
                                                                                                                                                      5




Contents
How To Use This Soil Survey ................................. 3                3400A—Calco silty clay loam, 0 to 2 percent
Numerical Index to Map Units ............................. 10                      slopes, frequently flooded ............................ 36
Foreword ............................................................... 13    8400A—Calco silty clay loam, 0 to 2 percent
General Nature of the Survey Area ......................... 15                     slopes, occasionally flooded ........................ 37
  Settlement, Industry, and Farming ...................... 15                  Chute Series ...................................................... 37
  Relief, Physiography, and Drainage .................... 16                   Coatsburg Series ............................................... 38
  Climate ............................................................... 17   Coffeen Series ................................................... 39
How This Survey Was Made ................................... 18                3428A—Coffeen silt loam, 0 to 2 percent
Formation and Classification of the Soils .......... 21                            slopes, frequently flooded ............................ 40
  Factors of Soil Formation ................................... 21             7428A—Coffeen silt loam, 0 to 2 percent
     Parent Material ............................................... 21            slopes, rarely flooded ................................... 40
     Living Organisms ........................................... 21           Coloma Series .................................................... 41
     Climate ........................................................... 21    689B—Coloma sand, 1 to 7 percent slopes ....... 41
     Topography .................................................... 21        689D—Coloma sand, 7 to 15 percent
     Time ............................................................... 22       slopes .......................................................... 42
  Classification of the Soils .................................... 22          Coyne Series ...................................................... 42
Soil Series and Detailed Soil Map Units .............. 25                      764A—Coyne fine sandy loam, 0 to 2
  Ambraw Series ................................................... 26             percent slopes ............................................. 43
  8302A—Ambraw loam, 0 to 2 percent                                            764C—Coyne fine sandy loam, 5 to 10
      slopes, occasionally flooded ........................ 27                     percent slopes ............................................. 44
  Atlas Series ........................................................ 27     Denny Series ...................................................... 44
  Atterberry Series ................................................ 28        45A—Denny silt loam, 0 to 2 percent slopes ...... 45
  61A—Atterberry silt loam, 0 to 2 percent                                     Dickinson Series ................................................ 46
      slopes .......................................................... 29     87A—Dickinson sandy loam, 0 to 2 percent
  Biggsville Series ................................................. 30           slopes .......................................................... 46
  671A—Biggsville silt loam, 0 to 2 percent                                    87C2—Dickinson sandy loam, 5 to 10
      slopes .......................................................... 30         percent slopes, eroded ................................ 47
  671B—Biggsville silt loam, 2 to 5 percent                                    Dorchester Series .............................................. 47
      slopes .......................................................... 31     3239A—Dorchester silt loam, 0 to 2 percent
  Birds Series ........................................................ 31         slopes, frequently flooded ............................ 48
  1334A—Birds silt loam, undrained, 0 to 2                                     7239A—Dorchester silt loam, 0 to 2 percent
      percent slopes, frequently flooded ............... 32                        slopes, rarely flooded ................................... 48
  Bold Series ......................................................... 32     Elkhart Series ..................................................... 49
  Buckhart Series .................................................. 33        567C2—Elkhart silt loam, 5 to 10 percent
  705A—Buckhart silt loam, 0 to 2 percent                                          slopes, eroded ............................................. 50
      slopes .......................................................... 34     567D2—Elkhart silt loam, 10 to 18 percent
  Burkhardt Series ................................................ 34             slopes, eroded ............................................. 50
  961A—Burkhardt-Saude complex, 0 to 2                                         Fayette Series .................................................... 51
      percent slopes ............................................. 35          280B—Fayette silt loam, 2 to 5 percent
  Calco Series ....................................................... 35          slopes .......................................................... 51
  1400A—Calco silty clay loam, undrained,                                      280B2—Fayette silt loam, 2 to 5 percent
      0 to 2 percent slopes, frequently flooded ..... 36                           slopes, eroded ............................................. 52
6




    280C2—Fayette silt loam, 5 to 10 percent                                   763B—Joslin silt loam, 2 to 5 percent
        slopes, eroded ............................................. 52             slopes .......................................................... 67
    280C3—Fayette silty clay loam, 5 to 10                                     Joy Series .......................................................... 67
        percent slopes, severely eroded .................. 53                  275A—Joy silt loam, 0 to 2 percent slopes ......... 68
    3646L—Fluvaquents, loamy, 0 to 2 percent                                   Landes Series .................................................... 69
        slopes, frequently flooded, long duration ...... 53                    7304A—Landes fine sandy loam, 0 to 2
    Greenbush Series .............................................. 54              percent slopes, rarely flooded ...................... 69
    675A—Greenbush silt loam, 0 to 2 percent                                   Lawler Series ..................................................... 70
        slopes .......................................................... 55   647A—Lawler loam, 0 to 2 percent slopes ......... 71
    675B—Greenbush silt loam, 2 to 5 percent                                   Lawson Series .................................................... 71
        slopes .......................................................... 55   3451A—Lawson silt loam, 0 to 2 percent
    Hickory Series .................................................... 56          slopes, frequently flooded ............................ 72
    8D2—Hickory silt loam, 10 to 18 percent                                    7451A—Lawson silt loam, 0 to 2 percent
        slopes, eroded ............................................. 57             slopes, rarely flooded ................................... 72
    8D3—Hickory clay loam, 10 to 18 percent                                    Marseilles Series ................................................ 72
        slopes, severely eroded ............................... 57             913D2—Marseilles-Hickory silt loams, 10
    8F—Hickory silt loam, 18 to 35 percent                                          to 18 percent slopes, eroded ........................ 73
        slopes .......................................................... 58   913F—Marseilles-Hickory silt loams, 18 to
    8F3—Hickory clay loam, 18 to 35 percent                                         35 percent slopes ........................................ 74
        slopes, severely eroded ............................... 58             913G—Marseilles-Hickory silt loams, 35 to
    898F3—Hickory-Sylvan complex, 18 to 35                                          60 percent slopes ........................................ 75
        percent slopes, severely eroded .................. 59                  Martinsville Series .............................................. 75
    898G—Hickory-Sylvan silt loams, 35 to 60                                   570B—Martinsville silt loam, 2 to 5 percent
        percent slopes ............................................. 59             slopes .......................................................... 76
    946D3—Hickory-Atlas complex, 10 to 18                                      570C3—Martinsville clay loam, 5 to 10
        percent slopes, severely eroded .................. 60                       percent slopes, severely eroded .................. 77
    946F3—Hickory-Atlas complex, 18 to 35                                      570D3—Martinsville clay loam, 10 to 18
        percent slopes, severely eroded .................. 61                       percent slopes, severely eroded .................. 77
    960D2—Hickory-Sylvan-Fayette silt loams,                                   Millington Series ................................................. 78
        10 to 18 percent slopes, eroded ................... 61                 1082A—Millington silt loam, undrained,
    960D3—Hickory-Sylvan-Fayette complex,                                           0 to 2 percent slopes, frequently flooded ..... 78
        10 to 18 percent slopes, severely eroded ..... 62                      3082A—Millington silt loam, 0 to 2 percent
    960F—Hickory-Sylvan-Fayette silt loams,                                         slopes, frequently flooded ............................ 79
        18 to 30 percent slopes ................................ 63            Millsdale Series .................................................. 79
    Hoopeston Series ............................................... 64        317A—Millsdale silty clay loam, 0 to 2
    172A—Hoopeston sandy loam, 0 to 2                                               percent slopes ............................................. 80
        percent slopes ............................................. 65        M-W—Miscellaneous water ................................ 80
    Joslin Series ....................................................... 65   Moline Series ..................................................... 80
    525A—Joslin loam, bedrock substratum,                                      1654A—Moline silty clay, undrained, 0 to 2
        0 to 2 percent slopes .................................... 66               percent slopes, frequently flooded ............... 81
    763A—Joslin silt loam, 0 to 2 percent                                      7654A—Moline silty clay, 0 to 2 percent
        slopes .......................................................... 66        slopes, rarely flooded ................................... 81
                                                                                                                                                  7




Muscatune Series .............................................. 82         279A—Rozetta silt loam, 0 to 2 percent
51A—Muscatune silt loam, 0 to 2 percent                                        slopes .......................................................... 97
    slopes .......................................................... 83   279B—Rozetta silt loam, 2 to 5 percent
Niota Series ........................................................ 83       slopes .......................................................... 97
261A—Niota silt loam, 0 to 2 percent                                       Sable Series ....................................................... 98
    slopes .......................................................... 84   68A—Sable silty clay loam, 0 to 2 percent
Oakville Series ................................................... 85         slopes .......................................................... 99
741F—Oakville fine sand, 20 to 30 percent                                  Saude Series ...................................................... 99
    slopes .......................................................... 85   774A—Saude loam, 0 to 2 percent slopes ....... 100
917C2—Oakville-Tell complex, 5 to 10                                       Sawmill Series .................................................. 100
    percent slopes, eroded ................................ 85             1107A—Sawmill silty clay loam, undrained,
917D2—Oakville-Tell complex, 10 to 18                                          0 to 2 percent slopes, frequently
    percent slopes, eroded ................................ 86                 flooded ....................................................... 101
Orion Series ....................................................... 87    3107A—Sawmill silty clay loam, 0 to 2
3415A—Orion silt loam, 0 to 2 percent                                          percent slopes, frequently flooded ............. 101
    slopes, frequently flooded ............................ 87             7107A—Sawmill silty clay loam, 0 to 2
7415A—Orion silt loam, 0 to 2 percent                                          percent slopes, rarely flooded .................... 102
    slopes, rarely flooded ................................... 88          8107+—Sawmill silt loam, 0 to 2 percent
802B—Orthents, loamy, undulating .................... 88                       slopes, occasionally flooded, overwash ..... 102
Osco Series ....................................................... 89     Seaton Series ................................................... 103
86B—Osco silt loam, 2 to 5 percent slopes ........ 90                      274B—Seaton silt loam, 2 to 5 percent
86C2—Osco silt loam, 5 to 10 percent                                           slopes ........................................................ 104
    slopes, eroded ............................................. 90        274B2—Seaton silt loam, 2 to 5 percent
Otter Series ........................................................ 91       slopes, eroded ........................................... 104
1076A—Otter silt loam, undrained, 0 to 2                                   274C2—Seaton silt loam, 5 to 10 percent
    percent slopes, frequently flooded ............... 91                      slopes, eroded ........................................... 105
3076A—Otter silt loam, 0 to 2 percent slopes,                              274D2—Seaton silt loam, 10 to 18 percent
    frequently flooded ........................................ 92             slopes, eroded ........................................... 105
7076A—Otter silt loam, 0 to 2 percent slopes,                              943D2—Seaton-Timula silt loams, 10 to 18
    rarely flooded ............................................... 92          percent slopes, eroded .............................. 105
864—Pits, quarries ............................................. 93        943F2—Seaton-Timula silt loams, 18 to 35
865—Pits, gravel ................................................ 93           percent slopes, eroded .............................. 106
800C—Psamments, sloping ............................... 93                 Sparta Series ................................................... 107
Raddle Series ..................................................... 93     88A—Sparta loamy sand, 0 to 2 percent
430A—Raddle silt loam, 0 to 2 percent                                          slopes ........................................................ 107
    slopes .......................................................... 94   Strawn Series ................................................... 108
430B—Raddle silt loam, 2 to 5 percent                                      959G—Strawn-Chute complex, 18 to 60
    slopes .......................................................... 95       percent slopes ........................................... 108
Radford Series ................................................... 95      Stronghurst Series ........................................... 109
3074A—Radford silt loam, 0 to 2 percent                                    278A—Stronghurst silt loam, 0 to 2 percent
    slopes, frequently flooded ............................ 96                 slopes ........................................................ 110
Rozetta Series .................................................... 96     Sylvan Series ................................................... 110
8




  19C3—Sylvan silty clay loam, 5 to 10                                          Recreation ........................................................ 130
       percent slopes, severely eroded ................ 111                     Wildlife Habitat ................................................. 131
  19D—Sylvan silt loam, 10 to 18 percent                                        Hydric Soils ...................................................... 132
       slopes ........................................................ 112      Engineering ...................................................... 133
  19D3—Sylvan silty clay loam, 10 to 18                                             Building Site Development ........................... 133
       percent slopes, severely eroded ................ 112                         Sanitary Facilities ......................................... 134
  19F—Sylvan silt loam, 18 to 35 percent                                            Construction Materials ................................. 136
       slopes ........................................................ 113          Water Management ...................................... 137
  19F3—Sylvan silty clay loam, 18 to 35                                       Soil Properties .................................................... 139
       percent slopes, severely eroded ................ 113                     Engineering Index Properties ........................... 139
  962F—Sylvan-Bold silt loams, 18 to 35                                         Physical Properties .......................................... 140
       percent slopes ........................................... 114           Chemical Properties ......................................... 141
  Tell Series ......................................................... 114     Water Features ................................................. 141
  Thebes Series .................................................. 115          Soil Features .................................................... 142
  212B—Thebes silt loam, 2 to 5 percent                                       References .......................................................... 145
       slopes ........................................................ 116    Glossary .............................................................. 147
  Timula Series ................................................... 116       Tables .................................................................. 157
  Titus Series ...................................................... 117       Table 1.—Temperature and Precipitation .......... 158
  8404A—Titus silty clay loam, 0 to 2 percent                                   Table 2.—Freeze Dates in Spring and Fall ........ 159
       slopes, occasionally flooded ...................... 118                  Table 3.—Growing Season ............................... 159
  Velma Series .................................................... 119         Table 4.—Classification of the Soils .................. 160
  250D—Velma silt loam, 10 to 18 percent                                        Table 5.—Acreage and Proportionate
       slopes ........................................................ 119           Extent of the Soils ...................................... 162
  944D2—Velma-Coatsburg silt loams, 10 to                                       Table 6.—Land Capability and Yields per
       18 percent slopes, eroded ......................... 120                       Acre of Crops and Pasture ......................... 164
  Wabash Series ................................................. 120           Table 7.—Prime Farmland ................................ 170
  3083A—Wabash silty clay, 0 to 2 percent                                       Table 8.—Forestland Productivity ..................... 172
       slopes, frequently flooded .......................... 121                Table 9a.—Forestland Management ................. 177
  7083A—Wabash silty clay, 0 to 2 percent                                       Table 9b.—Forestland Management ................. 182
       slopes, rarely flooded ................................. 122             Table 9c.—Forestland Management ................. 187
  Waukee Series ................................................. 122           Table 9d.—Forestland Management ................. 191
  727A—Waukee loam, 0 to 2 percent                                              Table 9e.—Forestland Management ................. 194
       slopes ........................................................ 123      Table 10.—Windbreaks and Environmental
Use and Management of the Soils .................... 125                             Plantings .................................................... 196
  Interpretive Ratings .......................................... 125           Table 11a.—Recreation .................................... 220
     Rating Class Terms ...................................... 125              Table 11b.—Recreation .................................... 230
     Numerical Ratings ........................................ 125             Table 12.—Wildlife Habitat ................................ 239
  Crops and Pasture ........................................... 125             Table 13.—Hydric Soils .................................... 246
     Crop Yield Estimates .................................... 126              Table 14a.—Building Site Development ............ 249
     Land Capability Classification ...................... 126                  Table 14b.—Building Site Development ............ 260
     Prime Farmland ........................................... 127             Table 15.—Sanitary Facilities ........................... 273
  Forestland Management and Productivity ........ 127                           Table 16.—Construction Materials .................... 292
  Windbreaks and Environmental Plantings ........ 129                           Table 17a.—Water Management ...................... 312
                                                                                                                          9




Table 17b.—Water Management ...................... 323       Table 20.—Chemical Properties of the Soils ..... 371
Table 18.—Engineering Index Properties ......... 336         Table 21.—Water Features ............................... 382
Table 19.—Physical Properties of the Soils ...... 360        Table 22.—Soil Features .................................. 389


                                                   Issued 2004
10




Numerical Index to Map Units
8D2—Hickory silt loam, 10 to 18 percent                                         274B2—Seaton silt loam, 2 to 5 percent
  slopes, eroded .................................................... 57          slopes, eroded .................................................. 104
8D3—Hickory clay loam, 10 to 18 percent                                         274C2—Seaton silt loam, 5 to 10 percent
  slopes, severely eroded ...................................... 57               slopes, eroded .................................................. 105
8F—Hickory silt loam, 18 to 35 percent                                          274D2—Seaton silt loam, 10 to 18 percent
  slopes ................................................................. 58     slopes, eroded .................................................. 105
8F3—Hickory clay loam, 18 to 35 percent                                         275A—Joy silt loam, 0 to 2 percent slopes ............. 68
  slopes, severely eroded ...................................... 58             278A—Stronghurst silt loam, 0 to 2 percent
19C3—Sylvan silty clay loam, 5 to 10 percent                                      slopes ............................................................... 110
  slopes, severely eroded .................................... 111              279A—Rozetta silt loam, 0 to 2 percent
19D—Sylvan silt loam, 10 to 18 percent                                            slopes ................................................................. 97
  slopes ............................................................... 112    279B—Rozetta silt loam, 2 to 5 percent
19D3—Sylvan silty clay loam, 10 to 18 percent                                     slopes ................................................................. 97
  slopes, severely eroded .................................... 112              280B—Fayette silt loam, 2 to 5 percent
19F—Sylvan silt loam, 18 to 35 percent                                            slopes ................................................................. 51
  slopes ............................................................... 113    280B2—Fayette silt loam, 2 to 5 percent
19F3—Sylvan silty clay loam, 18 to 35 percent                                     slopes, eroded .................................................... 52
  slopes, severely eroded .................................... 113              280C2—Fayette silt loam, 5 to 10 percent
45A—Denny silt loam, 0 to 2 percent                                               slopes, eroded .................................................... 52
  slopes ................................................................. 45   280C3—Fayette silty clay loam, 5 to 10
51A—Muscatune silt loam, 0 to 2 percent                                           percent slopes, severely eroded ......................... 53
  slopes ................................................................. 83   317A—Millsdale silty clay loam, 0 to 2 percent
61A—Atterberry silt loam, 0 to 2 percent                                          slopes ................................................................. 80
  slopes ................................................................. 29   430A—Raddle silt loam, 0 to 2 percent
68A—Sable silty clay loam, 0 to 2 percent                                         slopes ................................................................. 94
  slopes ................................................................. 99   430B—Raddle silt loam, 2 to 5 percent
86B—Osco silt loam, 2 to 5 percent slopes ............ 90                         slopes ................................................................. 95
86C2—Osco silt loam, 5 to 10 percent slopes,                                    525A—Joslin loam, bedrock substratum,
  eroded ................................................................ 90      0 to 2 percent slopes .......................................... 66
87A—Dickinson sandy loam, 0 to 2 percent                                        567C2—Elkhart silt loam, 5 to 10 percent
  slopes ................................................................. 46     slopes, eroded .................................................... 50
87C2—Dickinson sandy loam, 5 to 10 percent                                      567D2—Elkhart silt loam, 10 to 18 percent
  slopes, eroded .................................................... 47          slopes, eroded .................................................... 50
88A—Sparta loamy sand, 0 to 2 percent                                           570B—Martinsville silt loam, 2 to 5 percent
  slopes ............................................................... 107      slopes ................................................................. 76
172A—Hoopeston sandy loam, 0 to 2 percent                                       570C3—Martinsville clay loam, 5 to 10 percent
  slopes ................................................................. 65     slopes, severely eroded ...................................... 77
212B—Thebes silt loam, 2 to 5 percent                                           570D3—Martinsville clay loam, 10 to 18
  slopes ............................................................... 116      percent slopes, severely eroded ......................... 77
250D—Velma silt loam, 10 to 18 percent                                          647A—Lawler loam, 0 to 2 percent slopes ............. 71
  slopes ............................................................... 119    671A—Biggsville silt loam, 0 to 2 percent
261A—Niota silt loam, 0 to 2 percent slopes .......... 84                         slopes ................................................................. 30
274B—Seaton silt loam, 2 to 5 percent                                           671B—Biggsville silt loam, 2 to 5 percent
  slopes ............................................................... 104      slopes ................................................................. 31
                                                                                                                                                     11




675A—Greenbush silt loam, 0 to 2 percent                                        946D3—Hickory-Atlas complex, 10 to 18
  slopes ................................................................. 55     percent slopes, severely eroded ......................... 60
675B—Greenbush silt loam, 2 to 5 percent                                        946F3—Hickory-Atlas complex, 18 to 35
  slopes ................................................................. 55     percent slopes, severely eroded ......................... 61
689B—Coloma sand, 1 to 7 percent slopes ............ 41                         959G—Strawn-Chute complex, 18 to 60
689D—Coloma sand, 7 to 15 percent                                                 percent slopes .................................................. 108
  slopes ................................................................. 42   960D2—Hickory-Sylvan-Fayette silt loams,
705A—Buckhart silt loam, 0 to 2 percent                                           10 to 18 percent slopes, eroded ......................... 61
  slopes ................................................................. 34   960D3—Hickory-Sylvan-Fayette complex,
727A—Waukee loam, 0 to 2 percent slopes ......... 123                             10 to 18 percent slopes, severely eroded ........... 62
741F—Oakville fine sand, 20 to 30 percent                                       960F—Hickory-Sylvan-Fayette silt loams, 18
  slopes ................................................................. 85     to 30 percent slopes ........................................... 63
763A—Joslin silt loam, 0 to 2 percent slopes ......... 66                       961A—Burkhardt-Saude complex, 0 to 2
763B—Joslin silt loam, 2 to 5 percent slopes ......... 67                         percent slopes .................................................... 35
764A—Coyne fine sandy loam, 0 to 2 percent                                      962F—Sylvan-Bold silt loams, 18 to 35
  slopes ................................................................. 43     percent slopes .................................................. 114
764C—Coyne fine sandy loam, 5 to 10                                             1076A—Otter silt loam, undrained, 0 to 2
  percent slopes .................................................... 44          percent slopes, frequently flooded ...................... 91
774A—Saude loam, 0 to 2 percent                                                 1082A—Millington silt loam, undrained, 0 to 2
  slopes ............................................................... 100      percent slopes, frequently flooded ...................... 78
800C—Psamments, sloping ................................... 93                  1107A—Sawmill silty clay loam, undrained,
802B—Orthents, loamy, undulating ........................ 88                      0 to 2 percent slopes, frequently flooded .......... 101
864—Pits, quarries ................................................. 93         1334A—Birds silt loam, undrained, 0 to 2
865—Pits, gravel .................................................... 93          percent slopes, frequently flooded ...................... 32
898F3—Hickory-Sylvan complex, 18 to 35                                          1400A—Calco silty clay loam, undrained, 0 to 2
  percent slopes, severely eroded ......................... 59                    percent slopes, frequently flooded ...................... 36
898G—Hickory-Sylvan silt loams, 35 to 60                                        1654A—Moline silty clay, undrained, 0 to 2
  percent slopes .................................................... 59          percent slopes, frequently flooded ...................... 81
913D2—Marseilles-Hickory silt loams, 10 to 18                                   3074A—Radford silt loam, 0 to 2 percent
  percent slopes, eroded ....................................... 73               slopes, frequently flooded ................................... 96
913F—Marseilles-Hickory silt loams, 18 to 35                                    3076A—Otter silt loam, 0 to 2 percent slopes,
  percent slopes .................................................... 74          frequently flooded ............................................... 92
913G—Marseilles-Hickory silt loams, 35 to 60                                    3082A—Millington silt loam, 0 to 2 percent
  percent slopes .................................................... 75          slopes, frequently flooded ................................... 79
917C2—Oakville-Tell complex, 5 to 10 percent                                    3083A—Wabash silty clay, 0 to 2 percent
  slopes, eroded .................................................... 85          slopes, frequently flooded ................................. 121
917D2—Oakville-Tell complex, 10 to 18                                           3107A—Sawmill silty clay loam, 0 to 2 percent
  percent slopes, eroded ....................................... 86               slopes, frequently flooded ................................. 101
943D2—Seaton-Timula silt loams, 10 to 18                                        3239A—Dorchester silt loam, 0 to 2 percent
  percent slopes, eroded ..................................... 105                slopes, frequently flooded ................................... 48
943F2—Seaton-Timula silt loams, 18 to 35                                        3400A—Calco silty clay loam, 0 to 2 percent
  percent slopes, eroded ..................................... 106                slopes, frequently flooded ................................... 36
944D2—Velma-Coatsburg silt loams, 10 to 18                                      3415A—Orion silt loam, 0 to 2 percent slopes,
  percent slopes, eroded ..................................... 120                frequently flooded ............................................... 87
12




3428A—Coffeen silt loam, 0 to 2 percent                                        7415A—Orion silt loam, 0 to 2 percent slopes,
  slopes, frequently flooded ................................... 40              rarely flooded ..................................................... 88
3451A—Lawson silt loam, 0 to 2 percent                                         7428A—Coffeen silt loam, 0 to 2 percent
  slopes, frequently flooded ................................... 72              slopes, rarely flooded ......................................... 40
3646L—Fluvaquents, loamy, 0 to 2 percent                                       7451A—Lawson silt loam, 0 to 2 percent
  slopes, frequently flooded, long                                               slopes, rarely flooded ......................................... 72
  duration .............................................................. 53   7654A—Moline silty clay, 0 to 2 percent
7076A—Otter silt loam, 0 to 2 percent slopes,                                    slopes, rarely flooded ......................................... 81
  rarely flooded ..................................................... 92      8107+—Sawmill silt loam, 0 to 2 percent
7083A—Wabash silty clay, 0 to 2 percent                                          slopes, occasionally flooded, overwash ............ 102
  slopes, rarely flooded ....................................... 122           8302A—Ambraw loam, 0 to 2 percent
7107A—Sawmill silty clay loam, 0 to 2 percent                                    slopes, occasionally flooded ............................... 27
  slopes, rarely flooded ....................................... 102           8400A—Calco silty clay loam, 0 to 2 percent
7239A—Dorchester silt loam, 0 to 2 percent                                       slopes, occasionally flooded ............................... 37
  slopes, rarely flooded ......................................... 48          8404A—Titus silty clay loam, 0 to 2 percent
7304A—Landes fine sandy loam, 0 to 2 percent                                     slopes, occasionally flooded ............................. 118
  slopes, rarely flooded ......................................... 69          M-W—Miscellaneous water .................................... 80
                                                                                                 13




Foreword
       This soil survey contains information that affects land use planning in this survey
    area. It contains predictions of soil behavior for selected land uses. The survey also
    highlights soil limitations, improvements needed to overcome the limitations, and the
    impact of selected land uses on the environment.
       This soil survey is designed for many different users. Farmers, foresters, and
    agronomists can use it to evaluate the potential of the soil and the management needed
    for maximum food and fiber production. Planners, community officials, engineers,
    developers, builders, and home buyers can use the survey to plan land use, select sites
    for construction, and identify special practices needed to ensure proper performance.
    Conservationists, teachers, students, and specialists in recreation, wildlife
    management, waste disposal, and pollution control can use the survey to help them
    understand, protect, and enhance the environment.
       Various land use regulations of Federal, State, and local governments may impose
    special restrictions on land use or land treatment. The information in this report is
    intended to identify soil properties that are used in making various land use or land
    treatment decisions. Statements made in this report are intended to help the land users
    identify and reduce the effects of soil limitations on various land uses. The landowner or
    user is responsible for identifying and complying with existing laws and regulations.
       Great differences in soil properties can occur within short distances. Some soils are
    seasonally wet or subject to flooding. Some are shallow to bedrock. Some are too
    unstable to be used as a foundation for buildings or roads. Clayey or wet soils are
    poorly suited to use as septic tank absorption fields. A high water table makes a soil
    poorly suited to basements or underground installations.
       These and many other soil properties that affect land use are described in this soil
    survey. The location of each soil is shown on the detailed soil maps. Each soil in the
    survey area is described, and information on specific uses is given. Help in using this
    publication and additional information are available at the local office of the Natural
    Resources Conservation Service or the Cooperative Extension Service.


    William J. Gradle
    State Conservationist
    Natural Resources Conservation Service
                                                                                                                        15




Soil Survey of
Rock Island County, Illinois
                 By Steve Elmer, Natural Resources Conservation Service

                 Original fieldwork by L.L. Acker, R.D. Busby, L.A. Dungan, G.T. Keller, R. Rehner,
                 L.M. Reinebach, J.A. Thompson, and S.E. Zwicker

                 Updated fieldwork by Steve Elmer and Dave Preloger, Natural Resources Conservation
                 Service

                 Compilation and resource analysis by Steve Elmer, Frank Heisner, Amy Kuhel, Dave
                 Preloger, and Jonathan Wald, Natural Resources Conservation Service

                 United States Department of Agriculture, Natural Resources Conservation Service,
                 in cooperation with the Illinois Agricultural Experiment Station




    ROCK ISLAND COUNTY is in northwestern Illinois                 complex known as the Quad Cities. This metropolitan
(fig. 1). It has a total area of about 288,910 acres, or           area includes Davenport and Bettendorf in Iowa and
451 square miles. It is bounded by Whiteside and                   Rock Island and Moline in Illinois.
Henry Counties on the east, by Mercer County on the                   The county has a well developed transportation
south, and by the Mississippi River on the west and                system. Interstate Highway 74 and U.S. Highways 6,
north.                                                             67, and 150 bisect the county from north to south.
    This soil survey updates the survey of Rock Island             Interstate 80 and Interstate 280 cross the county from
County published in 1977 (Acker, 1977). It provides                east to west. The county also has several State roads.
additional information and has larger maps, which                  The main secondary roads are blacktop. Railroads
show the soils in greater detail.                                  furnish freight service to the county. Facilities for
                                                                   loading commodities onto river barges are available
                                                                   along the Mississippi River. The Quad City Airport
General Nature of the Survey Area                                  offers connections to all points throughout the United
                                                                   States.
   This section provides some general information
                                                                      The Quad Cities is considered the “tractor capital of
about the survey area. It describes settlement,
                                                                   the world.” The county has several small industries and
industry, and farming; relief, physiography, and
                                                                   is also the home of the U.S. Army Weapons
drainage; and climate.
                                                                   Command, Rock Island Arsenal. Several limestone
                                                                   quarries and gravel pits provide crushed rock for
Settlement, Industry, and Farming                                  roads, finely ground material for limestone application
   This section was originally written by the late Emil Kubalek,   on fields, and sand and gravel for building materials.
former district conservationist, Rock Island County.               Hybrid seed corn is produced in the county. Cordova
                                                                   Township also has a large industrial complex. The
   Rock Island County was established in 1831. In                  nuclear generating station in Cordova Township
2000, the population of the county was 149,374 and                 provides power for much of east-central Iowa and
that of Rock Island, the county seat, was 39,684 (U.S.             northwestern Illinois and generates power for the
Department of Commerce, 2002).                                     Chicago metropolitan region.
   The center of the county is part of the metropolitan               The Quad Cities area offers many educational
16                                                                                                               Soil Survey of




                                                                                           LEGEND

                                                                95B—Southern Wisconsin and Northern Illinois Drift
                                                                   Plain

                                                                98—Southern Michigan and Northern Indiana Drift
                                                                   Plain

                                                                105—Northern Mississippi Valley Loess Hills

                                                                108A and 108B—Illinois and Iowa Deep Loess and
                                                                   Drift

                                                                110—Northern Illinois and Indiana Heavy Till Plain

                                                                113—Central Claypan Area

                                                                114B—Southern Illinois and Indiana Thin Loess and
                                                                   Till Plain

                                                                115A, 115B, and 115C—Central Mississippi Valley
                                                                   Wooded Slopes

                                                                120A—Kentucky and Indiana Sandstone and Shale
                                                                   Hills and Valleys

                                                                131A—Southern Mississippi Valley Alluvium

                                                                134—Southern Mississippi Valley Silty Uplands




                Figure 1.—Location of Rock Island County and major land resource areas (MLRAs) in Illinois.



facilities. Augustana College, Western Illinois                 the total number of swine was 35,900 (Illinois
University, and Blackhawk Junior College are on the             Agricultural Statistics Service, 2001). Sheep and
Illinois side of the Mississippi River. St. Ambrose             chickens also are raised.
College and Scott County Junior College are on the
Iowa side of the river.
    Farming has been a major enterprise in Rock Island          Relief, Physiography, and Drainage
County since its settlement. In 2000, there were 318               Dr. Richard C. Anderson, retired, Department of Geology,
farms in the county (Illinois Agricultural Statistics           Augustana College, helped prepare this section.
Service, 2001). Crops and livestock are raised in the
survey area.                                                       The topography of Rock Island County consists of
    Corn and soybeans are the main crops. In 2000,              upland plains, highly dissected valley sides, terraces,
the acreage used for corn was 65,000 and the                    and flood plains (fig. 2). Although the county was
acreage used for soybeans was 55,000 (Illinois                  covered by glaciers that greatly modified the pre-
Agricultural Statistics Service, 2001). Small grain and         existing landscape, the present topography is almost
hay also are grown in the county, and there are several         entirely the result of stream erosion (Willman and
apple orchards.                                                 Frye, 1970). Thus the upland plains represent a gently
    The total number of cattle in 2000 was 11,000, and          rolling surface produced by glacial deposition, and the
Rock Island County, Illinois                                                                                       17




flood plains and dissected valley sides are the result of     the floors of the valleys cut by the streams. The lower
subsequent stream erosion (Leighton and Brophy,               areas are subject to periodic flooding. The flood plains
1961).                                                        are underlain by water-deposited sand, silt, and clay.
   The upland plains are at elevations of 750 to 790          They are relatively shallow over limestone and shale
feet between the Mississippi River and Copperas and           bedrock. In the extreme northern end of the county,
Mill Creeks. They are at an elevation of about 810 feet       however, bedrock is at a depth of more than 100 feet.
south of Copperas and Mill Creeks and at an elevation         Sand and silt terraces are common on the flood plains.
of about 700 feet in Coe Township at the northern end            Erosion by tributaries of the Mississippi and Rock
of the county. The upland areas are remnants of a             Rivers has produced highly dissected topography
once-continuous glacial plain that extended far to the        adjacent to these main streams. In many places the
south and east (Leighton and Brophy, 1961). Although          local relief varies by more than 200 feet. Steep slopes
largely of glacial origin, the upland areas are covered       cause landslides and soil instability.
with 30 feet or more of wind-deposited loess. In most            The Mississippi River serves as the water source
places the loess is simply a veneer without a                 for Rock Island, Moline, and East Moline, and the
topographic expression of its own, but in Coe                 smaller towns and rural areas are supplied by wells
Township it has been deposited in long, narrow ridges         pumping from limestone crevices at depths of 100 to
as much as 50 feet high that give the topography a            300 feet.
distinct northwest-southeast orientation. Sand dunes
are on uplands in the extreme western part of the             Climate
county and in Coe Township.
   The flood plains are chiefly along the Mississippi            Table 1 gives data on temperature and precipitation
and Rock Rivers and on the Meredosia bottom lands.            for the survey area as recorded at Moline during the
The elevation on the flood plains ranges from 540 feet        period 1971 to 2000. Table 2 shows probable dates of
at the southwestern end of the county to 610 feet on          the first freeze in fall and the last freeze in spring.
the sand plains in the northern part. Flood plains are        Table 3 provides data on length of the growing season.




                                  Figure 2.—A physiographic map of Rock Island County.
18                                                                                                     Soil Survey of




   In winter, the average temperature is 25 degrees F        down into the unconsolidated material in which the soil
and the average daily minimum temperature is 16              formed. The unconsolidated material is devoid of roots
degrees. The lowest temperature on record, which             and other living organisms and has not been changed
occurred at Moline on February 3, 1996, is -28               by other biological activity.
degrees. In summer, the average temperature is 73               The soils and miscellaneous areas in the survey
degrees and the average daily maximum temperature            area are in an orderly pattern that is related to the
is 84 degrees. The highest recorded temperature,             geology, landforms, relief, climate, and natural
which occurred at Moline on August 18, 1936, is 106          vegetation of the area. Each kind of soil and
degrees.                                                     miscellaneous area is associated with a particular kind
   Growing degree days are shown in table 1. They            or segment of the landscape. By observing the soils
are equivalent to “heat units.” During the month,            and miscellaneous areas in the survey area and
growing degree days accumulate by the amount that            relating their position to specific segments of the
the average temperature each day exceeds a base              landscape, soil scientists develop a concept, or model,
temperature (50 degrees F). The normal monthly               of how the soils were formed. Thus, during mapping,
accumulation is used to schedule single or successive        this model enables the soil scientists to predict with a
plantings of a crop between the last freeze in spring        considerable degree of accuracy the kind of soil or
and the first freeze in fall.                                miscellaneous area at a specific location on the
   Total annual precipitation is 38.04 inches. Of this       landscape.
total, 24.30 inches, or about 64 percent, usually falls in      Individual soils on the landscape commonly merge
April through September. The growing season for most         into one another as their characteristics gradually
crops falls within this period. In 2 years out of 10, the    change. To construct an accurate map, however, soil
rainfall in April through September is less than 11.85       scientists must determine the boundaries between the
inches. The heaviest 1-day rainfall during the period of     soils. They can observe only a limited number of soil
record was 6.21 inches.                                      profiles. Nevertheless, these observations,
   The average seasonal snowfall is 33.7 inches. The         supplemented by an understanding of the soil-
greatest snow depth at any one time during the period        vegetation-landscape relationship, are sufficient to
of record was 29 inches. On average, 47 days of the          verify predictions of the kinds of soil in an area and to
year have at least 1 inch of snow on the ground. The         determine the boundaries.
number of such days varies greatly from year to year.           Soil scientists recorded the characteristics of the
                                                             soil profiles that they studied. They noted soil color,
How This Survey Was Made                                     texture, size and shape of soil aggregates, kind and
                                                             amount of rock fragments, distribution of plant roots,
   This survey was made to provide updated                   soil reaction, and other features that enable them to
information about the soils and miscellaneous areas in       identify soils. After describing the soils in the survey
Rock Island County, which is a subset of Major Land          area and determining their properties, the soil
Resource Areas 108B and 115C (fig. 1). Major land            scientists assigned the soils to taxonomic classes
resource areas (MLRAs) are geographically                    (units). Taxonomic classes are concepts. Each
associated land resource units that share a common           taxonomic class has a set of soil characteristics with
land use, elevation, topography, climate, water, soils,      precisely defined limits. The classes are used as a
and vegetation (USDA, 1981). Map unit design and the         basis for comparison to classify soils systematically.
soil descriptions are based on the occurrence of each        Soil taxonomy, the system of taxonomic classification
soil throughout the MLRA. In some cases a soil may           used in the United States, is based mainly on the kind
be referred to that was not mapped in the Rock Island        and character of soil properties and the arrangement
County subset but that is representative of the MLRA.        of horizons within the profile. After the soil scientists
   The information includes a description of the soils       classified and named the soils in the survey area, they
and miscellaneous areas and their location and a             compared the individual soils with similar soils in the
discussion of their properties and the subsequent            same taxonomic class in other areas so that they
effects on suitability, limitations, and management for      could confirm data and assemble additional data
specified uses. Soil scientists observed the steepness,      based on experience and research.
length, and shape of the slopes; the general pattern of         While a soil survey is in progress, samples of some
drainage; the kinds of crops and native plants; and the      of the soils in the area generally are collected for
kinds of bedrock. They dug many holes to study the           laboratory analyses and for engineering tests. Soil
soil profile, which is the sequence of natural layers, or    scientists interpret the data from these analyses and
horizons, in a soil. The profile extends from the surface    tests as well as the field-observed characteristics and
Rock Island County, Illinois                                                                                      19




the soil properties to determine the expected behavior       climate and biological activity. Soil conditions are
of the soils under different uses. Interpretations for all   predictable over long periods of time, but they are not
of the soils are field tested through observation of the     predictable from year to year. For example, soil
soils in different uses and under different levels of        scientists can predict with a fairly high degree of
management. Interpretations are modified as                  accuracy that a given soil will have a seasonal high
necessary to fit local conditions, and some new              water table within certain depths in most years, but
interpretations are developed to meet local needs.           they cannot predict that the water table will always be
Data are assembled from other sources, such as               at a specific level in the soil on a specific date.
research information, production records, and field             After soil scientists located and identified the
experience of specialists. For example, data on crop         significant natural bodies of soil in the survey area,
yields under defined levels of management are                they drew the boundaries of these bodies on aerial
assembled from farm records and from field or plot           photographs and identified each as a specific map
experiments on the same kinds of soil.                       unit. Aerial photographs show trees, buildings, fields,
   Predictions about soil behavior are based not only        roads, and rivers, all of which help in locating
on soil properties but also on such variables as             boundaries accurately.
                                                                                                                     21




Formation and Classification of the Soils
   This section relates the soils in the survey area to      Living Organisms
the major factors of soil formation and describes the
system of soil classification.                                  Plants have had a greater effect than animals on
                                                             the formation of soils in the survey area, but the
Factors of Soil Formation                                    animals and organisms that live on and in the soils
                                                             also have been important. The changes they bring
   The principal factors of soil formation are parent        about depend mainly on the kind of life processes
material, climate, plant and animal life, topography,        distinctive to each. The kinds of plants and animals
and time (Jenny, 1941). The relative importance of           that live on and in the soils are affected, in turn, by the
each factor differs from place to place, and each factor     climate, the parent material, the topography, and the
modifies the effect of the other four. In some cases         age of the soil.
one factor may dominate the formation of a soil.                Some soils in the county formed under trees, and
Human activities, such as clearing forests, cultivating      others formed under prairie grasses. Most of the
the soils, and using fertilizers, also change the course     sloping soils formed mainly under such trees as oak
of soil formation.                                           and hickory. The nearly level soils formed under prairie
                                                             grasses. These soils have a darker, thicker surface
Parent Material                                              layer than that of the soils that formed under forest
                                                             vegetation and have a higher content of organic
    Peoria loess is the predominant parent material of       matter.
the soils in Rock Island County (University of Illinois,
1971). The Mississippi River Valley was the main             Climate
source of the loess. The loess is about 30 feet thick on
nearly level uplands. Muscatune and Rozetta soils                Climate affects the formation of soils through its
formed in these thick deposits of loess. In areas on         influence on the rate of weathering of parent material.
slopes where the loess is thin or has been removed by        The humid, temperate climate of the county
erosion, the soils formed in such parent material as         contributes to the relatively rapid breakdown of soil
Illinoian till or Pennsylvania shale. Hickory soils formed   minerals, to the formation of clay, and to the movement
in Illinoian till, and Marseilles soils formed in            of these materials downward in the soil profile. Most of
Pennsylvania shale.                                          the upland soils in the county have considerably more
    Terraces are in the valleys of the Mississippi and       clay in the subsoil than in the surface layer.
Rock Rivers and in the valleys of the larger creeks. On
some of these terraces, Niota and Moline soils formed        Topography
in fine textured sediment. On other terraces, Sparta
and Dickinson soils formed in sandy parent material.            Relief influences the amount of runoff, the degree of
    Medium and moderately fine textured soils formed         erosion, and the amount of water infiltrating and
in alluvium in the valleys of the Mississippi and Rock       percolating through the soil profile. Where the soils
Rivers. Coffeen and Sawmill soils are common in              formed in uniform, permeable parent materials, such
these river valleys. In the smaller valleys, soils formed    as loess, natural drainage is closely associated with
mainly in recent medium textured sediment washed             slope. The moderately well drained and well drained
from the uplands. Dorchester, Radford, and Orion soils       soils are in the more rolling areas, and the somewhat
are examples.                                                poorly drained to very poorly drained soils are mainly
22                                                                                                    Soil Survey of




on flats or in depressions. Slopes in the county range      Table 4 shows the classification of the soils in the
from less than 2 percent on the bottom land and in the      survey area. The categories are defined in the
nearly level uplands to more than 60 percent on the         following paragraphs.
steeper parts of the uplands that border valleys.               ORDER. Twelve soil orders are recognized. The
                                                            differences among orders reflect the dominant soil-
Time                                                        forming processes and the degree of soil formation.
                                                            Each order is identified by a word ending in sol. An
    The length of time necessary for the development        example is Mollisol.
of a soil depends on the other factors of soil formation.       SUBORDER. Each order is divided into suborders
Soils that formed in parent material low in calcium         primarily on the basis of properties that influence soil
(lime) develop more readily and become acid more            genesis and are important to plant growth or
readily than soils that formed in material high in          properties that reflect the most important variables
calcium. Permeable soils are leached of calcium and         within the orders. The last syllable in the name of a
other soluble minerals much more rapidly than slowly        suborder indicates the order. An example is Aquoll
permeable soils. Soils form more quickly under forest       (Aqu, meaning water, plus oll, from Mollisol).
vegetation than under prairie vegetation because                GREAT GROUP. Each suborder is divided into
grasses are more efficient in recycling calcium and         great groups on the basis of close similarities in kind,
other bases from the subsoil to the surface layer. Soils    arrangement, and degree of development of
generally form more quickly in a humid climate than in      pedogenic horizons; soil moisture and temperature
a dry climate.                                              regimes; and base status. Each great group is
    In general, the longer the soils have been exposed      identified by the name of a suborder and by a prefix
to weathering processes, the more strongly developed        that indicates a property of the soil. An example is
they are and the more evidence they show of horizon         Endoaquolls (Endo, meaning within, plus aquoll, the
differentiation. Most of the soils on uplands are           suborder of the Mollisols that has an aquic moisture
moderately developed. The soils in the western and          regime).
northern parts of the county and on terraces, however,          SUBGROUP. Each great group has a typic
are only weakly developed. Because there has not            subgroup. Other subgroups are intergrades or
been enough time for changes to take place, most of         extragrades. The typic is the central concept of the
the soils on bottom land have no horizon differentiation    great group; it is not necessarily the most extensive.
or have only weakly expressed horizon differentiation.      Intergrades are transitions to other orders, suborders,
    Organic matter has accumulated in all of the soils.     or great groups. Extragrades have some properties
Soils that formed under prairie vegetation have a           that are not representative of the great group but do
thicker, darker surface layer than that of the soils that   not indicate transitions to any other known kind of soil.
formed under forest vegetation. In the poorly drained       Each subgroup is identified by one or more adjectives
soils, iron compounds have been reduced and moved           preceding the name of the great group. The adjective
downward in the profile. This process results in gray       Typic identifies the subgroup that typifies the great
colors in the subsoil. Some of this iron has                group. An example is Typic Endoaquolls.
accumulated as concretions or small, round pellets. In          FAMILY. Families are established within a
the well drained soils, the iron compounds are oxidized     subgroup on the basis of physical and chemical
and are generally more diffuse. They result in a            properties and other characteristics that affect
yellowish brown subsoil.                                    management. Generally, the properties are those of
                                                            horizons below plow depth where there is much
Classification of the Soils                                 biological activity. Among the properties and
                                                            characteristics considered are particle-size class,
   The system of soil classification used by the            mineral content, cation-exchange capacity,
National Cooperative Soil Survey has six categories         temperature regime, thickness of the root zone,
(Soil Survey Staff, 1999). Beginning with the broadest,     consistence, moisture equivalent, slope, and
these categories are the order, suborder, great group,      permanent cracks. A family name consists of the
subgroup, family, and series. Classification is based on    name of a subgroup preceded by terms that indicate
soil properties observed in the field or inferred from      soil properties. An example is fine-silty, mixed,
those observations or from laboratory measurements.         superactive, mesic Typic Endoaquolls.
Rock Island County, Illinois                                                                                23




   SERIES. The series consists of soils that have     arrangement in the profile. The texture of the surface
similar horizons in their profile. The horizons are   layer or of the substratum can differ within a series.
similar in color, texture, structure, reaction,       The Sable series is an example of a soil series in this
consistence, mineral and chemical composition, and    survey area.
                                                                                                                     25




Soil Series and Detailed Soil Map Units
    In this section, arranged in alphabetical order, each     the dominant soil or soils in the map unit, and thus
soil series recognized in the survey area is described.       they do not affect use and management. These are
Each series description is followed by detailed               called noncontrasting, or similar, components. They
descriptions of the associated soil map units.                may or may not be mentioned in a particular map unit
    Characteristics of the soil and the material in which     description. Other minor components, however, have
it formed are identified for each soil series. A pedon, a     properties and behavioral characteristics divergent
small three-dimensional area of soil, that is typical of      enough to affect use or to require different
the series in the survey area is described. The detailed      management. These are called contrasting, or
description of each soil horizon follows standards in         dissimilar, components. They generally are in small
the “Soil Survey Manual” (Soil Survey Division Staff,         areas and could not be mapped separately because of
1993). Many of the technical terms used in the                the scale used. Some small areas of strongly
descriptions are defined in “Keys to Soil Taxonomy”           contrasting soils or miscellaneous areas are identified
(Soil Survey Staff, 1998). Unless otherwise stated,           by a special symbol on the maps. The contrasting
colors in the descriptions are for moist soil. Following      components are mentioned in the map unit
the pedon description is the range of important               descriptions. A few areas of minor components may
characteristics of the soils in the series.                   not have been observed, and consequently they are
    The map units on the soil maps in this survey             not mentioned in the descriptions, especially where
represent the soils or miscellaneous areas in the             the pattern was so complex that it was impractical to
survey area. These soils or miscellaneous areas are           make enough observations to identify all the soils and
listed as individual components in the map unit               miscellaneous areas on the landscape.
description. The map unit descriptions in this section,           The presence of minor components in a map unit in
along with the maps, can be used to determine the             no way diminishes the usefulness or accuracy of the
suitability and potential of a unit for specific uses. They   data. The objective of mapping is not to delineate pure
also can be used to plan the management needed for            taxonomic classes but rather to separate the
those uses. More information about each map unit is           landscape into landforms or landform segments that
given under the headings “Use and Management of               have similar use and management requirements. The
the Soils” and “Soil Properties.”                             delineation of such segments on the map provides
    A map unit delineation on a soil map represents an        sufficient information for the development of resource
area dominated by one or more major kinds of soil or          plans. If intensive use of small areas is planned,
miscellaneous areas. A map unit is identified and             however, onsite investigation is needed to define and
named according to the taxonomic classification of the        locate the soils and miscellaneous areas.
dominant soils. Within a taxonomic class there are                An identifying symbol precedes the map unit name
precisely defined limits for the properties of the soils.     in the map unit descriptions. Each description includes
On the landscape, however, the soils are natural              general facts about the unit and gives some of the soil
phenomena, and they have the characteristic                   properties and qualities that may affect planning for
variability of all natural phenomena. Thus, the range of      specific uses.
some observed properties may extend beyond the                    Soils that have profiles that are almost alike make
limits defined for a taxonomic class. Areas of soils of a     up a soil series. Except for differences in texture of the
single taxonomic class rarely, if ever, can be mapped         surface layer, all the soils of a series have major
without including areas of other taxonomic classes.           horizons that are similar in composition, thickness,
Consequently, every map unit is made up of the soils          and arrangement.
or miscellaneous areas for which it is named and                  Soils of one series can differ in texture of the
some minor components that belong to taxonomic                surface layer, slope, stoniness, salinity, degree of
classes other than those of the major soils.                  erosion, and other characteristics that affect their use.
    Most minor soils have properties similar to those of      On the basis of such differences, a soil series is
26                                                                                                     Soil Survey of




divided into soil phases. Most of the areas shown on             fine subangular blocky structure parting to weak
the soil maps are phases of soil series. The name of a           fine granular; friable; many distinct black (10YR
soil phase commonly indicates a feature that affects             2/1) organic coatings on faces of peds; few fine
use or management. For example, Hickory silt loam,               prominent yellowish brown (10YR 5/6) iron oxide
10 to 18 percent slopes, eroded, is a phase of the               masses in the matrix; neutral; clear smooth
Hickory series.                                                  boundary.
    A map unit is named for the component or                  Bg1—20 to 27 inches; dark gray (10YR 4/1) clay loam;
components that make up a dominant percentage of                 moderate medium and fine subangular blocky
the map unit. Many map units consist of one dominant             structure; friable; many distinct very dark gray
component. These map units are consociations. Sable              (10YR 3/1) organic coatings on faces of peds; few
silty clay loam, 0 to 2 percent slopes, is an example.           fine concretions of iron oxide throughout the
    Some map units are made up of two or more                    matrix; common fine prominent strong brown
dominant components. These map units are                         (7.5YR 4/6) iron oxide masses in the matrix;
complexes. A complex consists of two or more                     neutral; clear smooth boundary.
components in such an intricate pattern or in such            Bg2—27 to 32 inches; dark gray (10YR 4/1) clay loam;
small areas that they cannot be shown separately on              weak medium prismatic structure; friable; few faint
the maps. Attempting to delineate the individual                 concretions of iron oxide throughout the matrix;
components of a complex would result in excessive                many medium prominent yellowish brown (10YR
clutter that could make the map illegible. The pattern           5/6) and few fine prominent strong brown (7.5YR
and proportion of the components in a complex are                4/6) iron oxide masses in the matrix; slightly acid;
somewhat similar in all areas. Marseilles-Hickory silt           clear smooth boundary.
loams, 35 to 60 percent slopes, is an example.                Bg3—32 to 36 inches; gray (5Y 5/1) clay loam; weak
    This survey includes miscellaneous areas. Such               medium subangular blocky structure; friable; very
areas have little or no soil material and support little or      dark gray (10YR 3/1) krotovina 1 inch wide at a
no vegetation. The map unit Pits, gravel, is an                  depth of 34 to 35 inches; few fine concretions of
example.                                                         iron oxide throughout the matrix; many medium
    Table 5 gives the acreage and proportionate extent           prominent yellowish brown (10YR 5/6) and few
of each map unit. Other tables (see Contents) give               fine prominent strong brown (7.5YR 4/6) iron oxide
properties of the soils and the limitations, capabilities,       masses in the matrix; neutral; abrupt smooth
and potentials for many uses. The Glossary defines               boundary.
many of the terms used in describing the soils or             Bg4—36 to 45 inches; gray (5Y 5/1) clay loam with
miscellaneous areas.                                             thin strata of gray (10YR 5/1) sandy clay loam;
                                                                 weak medium subangular blocky structure; friable;
                                                                 few fine soft masses of iron oxide throughout the
Ambraw Series                                                    matrix; few fine prominent brown (7.5YR 5/4) and
                                                                 common fine prominent yellowish brown (10YR
Taxonomic classification: Fine-loamy, mixed,
                                                                 5/6) iron oxide masses in the matrix; slightly acid;
   superactive, mesic Fluvaquentic Endoaquolls
                                                                 gradual smooth boundary.
                    Typical Pedon                             Cg—45 to 60 inches; stratified grayish brown (2.5Y
                                                                 5/2) clay loam, very dark grayish brown (2.5Y 3/2)
Ambraw clay loam, 0 to 2 percent slopes, rarely
                                                                 sandy clay loam, and brown (10YR 5/3) loamy
flooded; 2,400 feet north and 160 feet east of the
                                                                 sand; massive; friable; few fine prominent
southwest corner of sec. 11, T. 19 N., R. 3 E.; in
                                                                 yellowish brown (10YR 5/6) iron oxide masses in
Whiteside County, Illinois; USGS Erie Northwest
                                                                 the matrix; neutral.
topographic quadrangle; lat. 41 degrees 38 minutes 57
seconds N. and long. 90 degrees 07 minutes 54
                                                                          Range in Characteristics
seconds W., NAD 27:
                                                              Thickness of the mollic epipedon: 10 to 24 inches
Ap—0 to 10 inches; black (10YR 2/1) clay loam, very
                                                              Depth to free carbonates: More than 50 inches
   dark grayish brown (10YR 3/2) dry; weak fine
                                                              Thickness of the solum: 40 to 60 inches
   subangular blocky structure parting to weak fine
   granular; friable; slightly acid; abrupt smooth            Ap or A horizon:
   boundary.                                                      Hue—10YR, 2.5Y, or N
A—10 to 20 inches; very dark gray (10YR 3/1) clay                 Value—2 or 3
   loam, dark grayish brown (10YR 4/2) dry; weak                  Chroma—0 to 2
Rock Island County, Illinois                                                                                     27




    Texture—clay loam, loam, sandy loam, sandy clay       Hazard of corrosion: High for steel and moderate for
      loam, or silty clay loam                                concrete
                                                          Surface runoff class: Negligible
Bg horizon:
                                                          Susceptibility to water erosion: Slight
    Hue—10YR, 2.5Y, 5Y, or N
                                                          Susceptibility to wind erosion: Slight
    Value—4 to 6
    Chroma—0 to 2                                                         Interpretive Groups
    Texture—loam, clay loam, sandy clay loam, sandy
                                                          Land capability classification: 2w
      loam, or silt loam
                                                          Prime farmland status: Prime farmland where drained
Cg horizon:                                               Hydric soil status: Hydric
    Hue—10YR, 2.5Y, or 5Y
    Value—4 to 6
    Chroma—1 to 4                                         Atlas Series
    Texture—stratified sand, loamy sand, sandy loam,
      loam, silt loam, and clay loam                      Taxonomic classification: Fine, smectitic, mesic Aeric
                                                             Chromic Vertic Epiaqualfs
                                                          Map units in which this series occurs: 946D3, 946F3
8302A—Ambraw loam, 0 to 2 percent
   slopes, occasionally flooded                                              Typical Pedon
                                                          Atlas silt loam, 5 to 10 percent slopes, eroded, at an
                         Setting
                                                          elevation of 665 feet; 1,200 feet west and 50 feet south
Landform: Flood plains                                    of the northeast corner of sec. 7, T. 1 N., R. 6 W.; in
                                                          Warren County, Illinois; USGS Coatsburg topographic
                    Composition
                                                          quadrangle; lat. 40 degrees 05 minutes 40 seconds N.
Ambraw and similar soils: 95 percent                      and long. 91 degrees 07 minutes 52 seconds W., NAD
Dissimilar soils: 5 percent                               27:
                Minor Components                          Ap—0 to 7 inches; dark grayish brown (10YR 4/2) silt
                                                              loam, light brownish gray (10YR 6/2) dry; weak
Similar soils:
                                                              fine granular structure; friable; common very fine
• Soils that contain more clay in the lower part
                                                              and fine roots; common medium prominent brown
• Soils that have a thicker surface layer
                                                              (7.5YR 5/8) and few fine distinct yellowish brown
Dissimilar soils:                                             (10YR 5/6) masses of iron throughout; few fine
• Moderately well drained soils on footslopes                 prominent black (2.5Y 2/1) masses of iron and
                                                              manganese throughout; slightly acid; clear smooth
 Properties and Qualities of the Ambraw Soil
                                                              boundary.
Parent material: Alluvium                                 BE—7 to 13 inches; brown (10YR 5/3) silty clay loam,
Drainage class: Poorly drained                                light brownish gray (10YR 6/2) dry; weak medium
Slowest permeability within a depth of 40 inches:             subangular blocky structure; friable; common fine
    Moderately slow                                           roots; few fine distinct light brownish gray (10YR
Permeability below a depth of 60 inches: Moderately           6/2) clay depletions throughout; few fine distinct
    slow or moderate                                          yellowish brown (10YR 5/6) masses of iron
Depth to restrictive feature: More than 80 inches             throughout; slightly acid; clear wavy boundary.
Available water capacity to a depth of 60 inches: About   2Btg1—13 to 26 inches; dark gray (10YR 4/1) silty
    9.4 inches                                                clay loam; moderate thick platy structure parting to
Content of organic matter in the surface layer: 2 to 3        weak fine subangular blocky; firm; common fine
    percent                                                   and few medium roots; common distinct very dark
Shrink-swell potential: Moderate                              gray (10YR 3/1) organo-clay films on faces of
Depth and months of the highest apparent seasonal             peds and in pores; few fine prominent yellowish
    high water table: At the surface, January to May          brown (10YR 5/6) masses of iron and few fine
Ponding depth: 0.2 foot during wet periods                    distinct white (10YR 8/1) masses of barite
Frequency and most likely period of flooding:                 throughout; moderately acid; clear wavy boundary.
    Occasional, November to June                          2Btg2—26 to 37 inches; 87 percent dark gray (10YR
Potential for frost action: High                              4/1) and 10 percent gray (10YR 5/1) silty clay;
28                                                                                                  Soil Survey of




    weak medium prismatic structure; firm; common             Chroma—0 to 2
    fine and medium roots; few distinct very dark gray        Texture—clay loam, clay, silty clay loam, or silty
    (10YR 3/1) organo-clay films on faces of peds and           clay
    in pores; common fine prominent yellowish brown           Content of rock fragments—0 to 5 percent
    (10YR 5/6) masses of iron and few fine distinct
                                                          2Cg horizon (if it occurs):
    white (10YR 8/1) masses of barite throughout;
                                                             Hue—10YR, 7.5YR, 2.5Y, 5Y, or N
    1 percent rounded gravel and 1 percent
                                                             Value—4 to 6
    subangular limestone-cherty gravel; neutral; clear
                                                             Chroma—0 to 6
    wavy boundary.
                                                             Texture—silty clay loam, clay loam, or loam
2Btg3—37 to 47 inches; gray (2.5Y 5/1) silty clay;
                                                             Content of rock fragments—2 to 15 percent
    weak coarse prismatic structure; firm; common
    fine roots; few distinct very dark gray (10YR 3/1)
    organo-clay films on faces of peds and in pores;      Atterberry Series
    few fine prominent yellowish brown (10YR 5/6)
    masses of iron throughout; few fine faint gray        Taxonomic classification: Fine-silty, mixed,
    (10YR 6/1) iron depletions and few fine distinct         superactive, mesic Udollic Endoaqualfs
    white (10YR 8/1) masses of barite throughout;
                                                            Typical Pedon (Official Series Description)
    1 percent angular gravel; neutral; clear wavy
    boundary.                                             Atterberry silt loam, 0 to 2 percent slopes; 1,650 feet
2Btg4—47 to 61 inches; gray (2.5Y 5/1) clay loam;         north and 1,120 feet east of the southwest corner of
    weak coarse prismatic structure; firm; common         sec. 34, T. 16 N., R. 9 E.; in Bureau County, Illinois;
    very fine roots; few distinct very dark gray (10YR    USGS Princeton South topographic quadrangle; lat. 41
    3/1) organo-clay films on faces of peds and in        degrees 19 minutes 30 seconds N. and long. 89
    pores; few fine distinct black (2.5Y 2/1) masses of   degrees 26 minutes 47 seconds W., NAD 27:
    iron and manganese and few fine distinct white
                                                          Ap—0 to 9 inches; very dark grayish brown (10YR 3/2)
    (10YR 8/1) barite crystals throughout; 1 percent
                                                             silt loam, brown (10YR 5/3) dry; moderate fine
    limestone-cherty gravel and 1 percent rounded
                                                             granular structure; friable; few fine roots; neutral;
    igneous-granite gravel; neutral; clear wavy
                                                             abrupt smooth boundary.
    boundary.
                                                          E—9 to 13 inches; light brownish gray (10YR 6/2) silt
2BCg—61 to 80 inches; light brownish gray (2.5Y 6/2)
                                                             loam; moderate thin platy structure; friable; few
    clay loam; weak coarse prismatic structure; firm;
                                                             fine roots; common fine faint grayish brown (10YR
    few fine distinct yellowish brown (10YR 5/6) and
                                                             5/2) redoximorphic depletions; slightly acid; clear
    common medium prominent brownish yellow
                                                             smooth boundary.
    (10YR 6/8) masses of iron throughout; 2 percent
                                                          BE—13 to 17 inches; brown (10YR 5/3) silt loam;
    limestone-cherty gravel; neutral.
                                                             moderate medium platy structure parting to
             Range in Characteristics                        moderate very fine subangular blocky; friable; few
                                                             fine roots; common faint brown (10YR 4/3) clay
Depth to the base of the argillic horizon: More than 42
                                                             films on faces of peds and common distinct light
   inches
                                                             gray (10YR 7/2) (dry) redoximorphic clay
Ap or A horizon:                                             depletions on faces of peds; few fine dark brown
    Hue—10YR                                                 (7.5YR 3/2) concretions of iron and manganese
    Value—2 to 5                                             oxide; few fine faint grayish brown (10YR 5/2) iron
    Chroma—1 to 4                                            depletions; slightly acid; clear smooth boundary.
    Texture—silt loam, loam, silty clay loam, or clay     Bt—17 to 24 inches; brown (10YR 5/3) silty clay loam;
       loam                                                  moderate fine subangular blocky structure; firm;
                                                             few fine roots; many faint dark grayish brown
E or BE horizon:
                                                             (10YR 4/2) clay films and common faint light gray
    Hue—10YR
                                                             (10YR 7/2) (dry) redoximorphic clay depletions on
    Value—4 or 5
                                                             faces of peds; common fine rounded dark brown
    Chroma—1 to 4
                                                             (7.5YR 3/2) concretions of iron and manganese
    Texture—silt loam or silty clay loam
                                                             oxide; common fine faint grayish brown (10YR 5/2)
Bt, Btg, or 2Btg horizon:                                    iron depletions and common fine distinct yellowish
    Hue—10YR, 2.5Y, 5Y, or N                                 brown (10YR 5/6) iron concentrations; strongly
    Value—4 to 6                                             acid; clear smooth boundary.
Rock Island County, Illinois                                                                                    29




Btg1—24 to 33 inches; grayish brown (2.5Y 5/2) silty       E horizon:
    clay loam; moderate medium subangular blocky               Value—4 to 6
    structure; friable; few fine roots; many distinct          Chroma—1 or 2
    grayish brown (10YR 5/2) clay films and few                Reaction—strongly acid to neutral
    distinct light gray (10YR 7/2) (dry) redoximorphic
                                                           Bt or Btg horizon:
    clay depletions on faces of peds; common fine
                                                               Hue—10YR, 2.5Y, or 5Y
    rounded dark brown (7.5YR 3/2) concretions of
                                                               Value—4 to 6
    iron and manganese oxide; common fine faint light
                                                               Chroma—2 to 4
    brownish gray (2.5Y 6/2) iron depletions and
                                                               Texture—silty clay loam or silt loam
    common fine distinct yellowish brown (10YR 5/6)
                                                               Reaction—strongly acid to neutral
    iron concentrations; strongly acid; clear smooth
    boundary.                                              C or Cg horizon:
Btg2—33 to 40 inches; light brownish gray (2.5Y 6/2)           Hue—10YR, 2.5Y, or 5Y
    silty clay loam; moderate medium prismatic                 Value—4 to 6
    structure parting to moderate medium subangular            Chroma—1 to 4
    blocky; friable; few fine roots; common distinct           Reaction—moderately acid to slightly alkaline
    grayish brown (10YR 5/2) clay films and few
    distinct light gray (10YR 7/2) (dry) redoximorphic
    clay depletions on faces of peds; many prominent       61A—Atterberry silt loam, 0 to 2 percent
    very dark grayish brown (10YR 3/2) clay films             slopes
    lining pores; common fine prominent rounded dark                              Setting
    brown (7.5YR 3/2) concretions of iron and
                                                           Landform: Ground moraines
    manganese oxide; many fine prominent yellowish
                                                           Position on the landform: Summits
    brown (10YR 5/6) iron concentrations; strongly
    acid; clear smooth boundary.                                               Composition
Btg3—40 to 48 inches; light brownish gray (2.5Y 6/2)
                                                           Atterberry and similar soils: 98 percent
    silty clay loam; moderate coarse prismatic
                                                           Dissimilar soils: 2 percent
    structure; friable; few fine roots; common distinct
    grayish brown (10YR 5/2) clay films on faces of                        Minor Components
    peds; many prominent very dark grayish brown           Similar soils:
    (10YR 3/2) clay films lining pores; many fine          • Soils that have more clay in the subsoil
    prominent yellowish brown (10YR 5/6) iron              • Eroded soils that have slopes of 2 to 5 percent; near
    concentrations; strongly acid; clear smooth            the head of drainageways
    boundary.
                                                           Dissimilar soils:
BCg—48 to 55 inches; light brownish gray (2.5Y 6/2)
                                                           • The well drained Fayette soils on shoulders
    silt loam; weak coarse prismatic structure; friable;
                                                           • The well drained Rozetta soils on summits
    common distinct grayish brown (10YR 5/2) clay
                                                           • The poorly drained Sable soils in depressions
    films on faces of peds; many prominent very dark
    grayish brown (10YR 3/2) clay films lining pores;      Properties and Qualities of the Atterberry Soil
    many medium prominent yellowish brown (10YR
                                                           Parent material: Loess
    5/6) iron concentrations; moderately acid; clear
                                                           Drainage class: Somewhat poorly drained
    smooth boundary.
                                                           Slowest permeability within a depth of 40 inches:
Cg—55 to 60 inches; light brownish gray (2.5Y 6/2) silt
                                                               Moderate
    loam; massive; friable; many medium prominent
                                                           Permeability below a depth of 60 inches: Moderate
    yellowish brown (10YR 5/6) iron concentrations;
                                                           Depth to restrictive feature: More than 80 inches
    slightly acid.
                                                           Available water capacity to a depth of 60 inches: About
             Range in Characteristics                          11.7 inches
                                                           Content of organic matter in the surface layer: 1.5 to
Thickness of the solum: 42 to 72 inches
                                                               3.5 percent
Ap or A horizon:                                           Shrink-swell potential: Moderate
    Value—2 or 3                                           Depth and months of the highest apparent seasonal
    Chroma—1 or 2                                              high water table: 0.5 foot, January to May
    Reaction—moderately acid to neutral                    Flooding: None
30                                                                                                    Soil Survey of




Accelerated erosion: None or slight                            loam; massive; friable; few fine black (7.5YR 2.5/1)
Potential for frost action: High                               iron and manganese oxide stains; slightly acid.
Hazard of corrosion: High for steel and moderate for
                                                                        Range in Characteristics
    concrete
Surface runoff class: Low                                  Thickness of the mollic epipedon: 10 to 20 inches
Susceptibility to water erosion: Slight                    Depth to the base of the cambic horizon: More than 42
Susceptibility to wind erosion: Slight                         inches
                Interpretive Groups                        Ap or A horizon:
                                                               Value—2 or 3
Land capability classification: 1
                                                               Chroma—1 to 3
Prime farmland status: Prime farmland where drained
                                                               Reaction—moderately acid to moderately alkaline
Hydric soil status: Not hydric
                                                           Bw or BC horizon:
                                                              Hue—7.5YR or 10YR
Biggsville Series                                             Value—3 to 5
                                                              Chroma—3 to 6
Taxonomic classification: Fine-silty, mixed,
                                                              Reaction—moderately acid to neutral
   superactive, mesic Typic Hapludolls
                                                           C or Cg horizon:
  Typical Pedon (Official Series Description)
                                                               Hue—7.5YR, 10YR, or 2.5Y
Biggsville silt loam, 0 to 2 percent slopes, at an             Value—4 to 6
elevation of 630 feet; 1,520 feet west and 200 feet            Chroma—2 to 6
south of the northeast corner of sec. 30, T. 19 N., R. 3       Reaction—slightly acid to moderately alkaline
E.; in Rock Island County, Illinois; USGS Hillsdale
topographic quadrangle; lat. 41 degrees 36 minutes 40
seconds N. and long. 90 degrees 12 minutes 00              671A—Biggsville silt loam, 0 to 2 percent
seconds W., NAD 27:                                           slopes
Ap—0 to 8 inches; very dark gray (10YR 3/1) silt loam,                             Setting
   grayish brown (10YR 5/2) dry; moderate very fine
                                                           Landform: Ground moraines
   and fine granular structure; friable; common fine
                                                           Position on the landform: Summits
   roots; neutral; abrupt smooth boundary.
AB—8 to 16 inches; very dark grayish brown (10YR                               Composition
   3/2) and brown (10YR 4/3) silt loam, grayish
                                                           Biggsville and similar soils: 95 percent
   brown (10YR 5/2) dry; moderate medium
                                                           Dissimilar soils: 5 percent
   subangular blocky structure parting to moderate
   fine granular; friable; few fine roots; neutral;                        Minor Components
   gradual smooth boundary.
                                                           Similar soils:
Bw1—16 to 32 inches; brown (10YR 4/3) and dark
                                                           • Soils that do not have a seasonal high water table
   yellowish brown (10YR 4/4) silt loam; moderate
                                                           within a depth of 6 feet
   medium prismatic structure parting to moderate
                                                           • Soils that have a surface layer more than 24 inches
   medium subangular blocky; friable; few fine roots;
                                                           thick
   few faint very dark grayish brown (10YR 3/2)
                                                           • Soils that are underlain by sand within a depth of 60
   organic coatings on faces of peds; slightly acid;
                                                           inches
   abrupt smooth boundary.
Bw2—32 to 47 inches; brown (10YR 4/3) silt loam;           Dissimilar soils:
   moderate medium prismatic structure; friable;           • The somewhat poorly drained Joy soils on summits
   common medium distinct brown (7.5YR 4/4) and
                                                           Properties and Qualities of the Biggsville Soil
   yellowish brown (10YR 5/6) masses of iron within
   peds; common medium distinct grayish brown              Parent material: Loess
   (10YR 5/2) iron depletions within peds; few fine        Drainage class: Well drained
   black (7.5YR 2.5/1) iron and manganese oxide            Slowest permeability within a depth of 40 inches:
   stains; slightly acid; gradual smooth boundary.             Moderate
Cg—47 to 80 inches; grayish brown (10YR 5/2), brown        Permeability below a depth of 60 inches: Moderate
   (7.5YR 4/4), and yellowish brown (10YR 5/6) silt        Depth to restrictive feature: More than 80 inches
Rock Island County, Illinois                                                                                       31




Available water capacity to a depth of 60 inches: About   Content of organic matter in the surface layer: 3 to 5
    12.8 inches                                               percent
Content of organic matter in the surface layer: 3 to 5    Shrink-swell potential: Low
    percent                                               Depth and months of the highest apparent seasonal
Shrink-swell potential: Low                                   high water table: 4 feet, February to April
Depth and months of the highest apparent seasonal         Flooding: None
    high water table: 4 feet, February to April           Potential for frost action: High
Flooding: None                                            Hazard of corrosion: Low for steel and moderate for
Accelerated erosion: None or slight                           concrete
Potential for frost action: High                          Surface runoff class: Low
Hazard of corrosion: Low for steel and moderate for       Susceptibility to water erosion: Slight
    concrete                                              Susceptibility to wind erosion: Slight
Surface runoff class: Low
                                                                          Interpretive Groups
Susceptibility to water erosion: Slight
Susceptibility to wind erosion: Slight                    Land capability classification: 2e
                                                          Prime farmland status: Prime farmland
                Interpretive Groups
                                                          Hydric soil status: Not hydric
Land capability classification: 1
Prime farmland status: Prime farmland
Hydric soil status: Not hydric                            Birds Series
                                                          Taxonomic classification: Fine-silty, mixed,
671B—Biggsville silt loam, 2 to 5 percent                    superactive, nonacid, mesic Typic Fluvaquents
   slopes                                                                    Typical Pedon
                        Setting
                                                          Birds silt loam, undrained, 0 to 2 percent slopes,
Landform: Ground moraines                                 frequently flooded; 2,050 feet north and 110 feet west
Position on the landform: Shoulders                       of the southeast corner of sec. 36, T. 5 N., R. 4 W.; in
                                                          McDonough County, Illinois; USGS Fandon
                    Composition
                                                          topographic quadrangle; lat. 40 degrees 22 minutes 26
Biggsville and similar soils: 96 percent                  seconds N. and long. 90 degrees 47 minutes 30
Dissimilar soils: 4 percent                               seconds W., NAD 27:
                Minor Components                          Ap—0 to 9 inches; dark gray (10YR 4/1) silt loam, pale
                                                             brown (10YR 6/3) dry; thin strata of dark gray
Similar soils:
                                                             (10YR 4/1), very dark gray (10YR 3/1), and light
• Soils that do not have a seasonal high water table
                                                             yellowish brown (10YR 6/4) silt loam; moderate
within a depth of 6 feet
                                                             fine granular structure; friable; few fine distinct
• Soils that have a surface layer more than 24 inches
                                                             yellowish brown (10YR 5/8) iron masses in the
thick
                                                             matrix; slightly effervescent; moderately alkaline;
• Soils that are underlain by sand within a depth of 60
                                                             abrupt smooth boundary.
inches
                                                          Cg1—9 to 22 inches; gray (10YR 5/1) silt loam; thin
Dissimilar soils:                                            strata of light gray (10YR 7/1) and dark gray
• The somewhat poorly drained Joy soils on summits           (10YR 4/1) silt loam; massive; friable; few fine
• The poorly drained Denny soils in depressions              distinct light brownish gray (10YR 6/2) iron
                                                             depletions and few fine distinct yellowish brown
Properties and Qualities of the Biggsville Soil
                                                             (10YR 5/8) iron masses in the matrix; few fine
Parent material: Loess                                       rounded black (7.5YR 2.5/1) concretions of iron-
Drainage class: Well drained                                 manganese oxide throughout the matrix; slightly
Slowest permeability within a depth of 40 inches:            effervescent; moderately alkaline; clear smooth
    Moderate                                                 boundary.
Permeability below a depth of 60 inches: Moderate         Cg2—22 to 37 inches; gray (10YR 5/1) silt loam; thin
Depth to restrictive feature: More than 80 inches            strata of dark gray (10YR 4/1) silt loam; massive;
Available water capacity to a depth of 60 inches: About      friable; common fine distinct light brownish gray
    12.8 inches                                              (10YR 6/2) iron depletions and common fine
32                                                                                                 Soil Survey of




   distinct yellowish brown (10YR 5/8) iron masses in     Content of organic matter in the surface layer: 2 to 4
   the matrix; few fine rounded black (7.5YR 2.5/1)           percent
   concretions of iron-manganese oxide throughout         Shrink-swell potential: Moderate
   the matrix; neutral; clear smooth boundary.            Depth and months of the highest apparent seasonal
Cg3—37 to 60 inches; light brownish gray (10YR 6/2)           high water table: At the surface, November to June
   silt loam; thin strata of dark gray (10YR 4/1) silt    Ponding depth: 0.2 foot during wet periods
   loam; massive; friable; common fine distinct dark      Frequency and most likely period of flooding:
   gray (10YR 4/1) iron depletions and common fine            Frequent, November to June
   and medium distinct yellowish brown (10YR 5/8)         Potential for frost action: High
   iron masses in the matrix; few fine rounded black      Hazard of corrosion: Moderate for steel and low for
   (7.5YR 2.5/1) concretions of iron-manganese                concrete
   oxide throughout the matrix; slightly acid.            Surface runoff class: Negligible
                                                          Susceptibility to water erosion: Slight
             Range in Characteristics
                                                          Susceptibility to wind erosion: Slight
Ap, A, or ACg horizon:
                                                                          Interpretive Groups
    Hue—10YR, 2.5Y, or 5Y
    Value—4 to 6                                          Land capability classification: 5w
    Chroma—1 or 2                                         Prime farmland status: Not prime farmland
                                                          Hydric soil status: Hydric
Cg horizon:
    Hue—10YR, 2.5Y, or 5Y
    Value—4 to 7                                          Bold Series
    Chroma—1 or 2
    Texture—silt loam; strata of silty clay loam, clay    Taxonomic classification: Coarse-silty, mixed,
      loam, loam, or sandy loam below a depth of 40          superactive, calcareous, mesic Typic Udorthents
      inches in some pedons                               Map unit in which this series occurs: 962F
                                                                             Typical Pedon
1334A—Birds silt loam, undrained, 0 to 2                  Bold silt loam, in an area of Sylvan-Bold complex,
   percent slopes, frequently flooded                     severely eroded, 10 to 18 percent slopes; 600 feet
                                                          north and 900 feet east of the southwest corner of sec.
                         Setting
                                                          7, T. 16 N., R. 3 E.; in Henry County, Illinois; USGS
Landform: Flood plains                                    Geneseo topographic quadrangle; lat. 41 degrees 23
                                                          minutes 04 seconds N. and long. 90 degrees 11
                    Composition
                                                          minutes 57 seconds W., NAD 27:
Birds and similar soils: 97 percent
                                                          Ap—0 to 8 inches; mixed brown (10YR 4/3), dark
Dissimilar soils: 3 percent
                                                             grayish brown (10YR 4/2), and yellowish brown
                Minor Components                             (10YR 5/4) silt loam, pale brown (10YR 6/3) and
                                                             light yellowish brown (10YR 6/4) dry; weak very
Similar soils:
                                                             fine and fine granular structure; friable; slightly
• Soils that have a thicker or darker surface layer
                                                             effervescent; moderately alkaline; abrupt smooth
Dissimilar soils:                                            boundary.
• The poorly drained Sawmill soils on toeslopes           C1—8 to 16 inches; yellowish brown (10YR 5/6) silt
• Well drained soils on footslopes                           loam; massive; friable; strongly effervescent;
                                                             moderately alkaline; abrupt smooth boundary.
     Properties and Qualities of the Birds Soil
                                                          C2—16 to 37 inches; light brownish gray (10YR 6/2)
Parent material: Alluvium                                    and yellowish brown (10YR 5/6) silt loam;
Drainage class: Poorly drained                               massive; friable; strongly effervescent; moderately
Slowest permeability within a depth of 40 inches:            alkaline; clear smooth boundary.
    Moderate                                              C3—37 to 60 inches; yellowish brown (10YR 5/6) and
Permeability below a depth of 60 inches: Moderate            light brownish gray (10YR 6/2) silt loam; massive;
Depth to restrictive feature: More than 80 inches            friable; strongly effervescent; moderately alkaline;
Available water capacity to a depth of 60 inches: About      clear wavy boundary.
    11.9 inches                                           C4—60 to 80 inches; light brownish gray (10YR 6/2)
Rock Island County, Illinois                                                                                      33




    and yellowish brown (10YR 5/6) silt loam;                  strong brown (7.5YR 5/6) masses of iron and
    massive; few coarse prominent strong brown                 manganese along pores and few fine irregular
    (7.5YR 5/8) iron concentrations; strongly                  prominent light brownish gray (2.5Y 6/2) iron
    effervescent; moderately alkaline.                         depletions along pores; neutral; clear smooth
                                                               boundary.
             Range in Characteristics
                                                            Bt3—37 to 52 inches; brown (10YR 5/3) silt loam;
Thickness of the loess: 6 to more than 30 feet                 weak medium subangular blocky structure; friable;
Thickness of the solum: 3 to 12 inches                         few very fine roots; common distinct dark grayish
                                                               brown (10YR 4/2) clay films on faces of peds;
Ap horizon:
                                                               common fine irregular prominent strong brown
    Hue—10YR
                                                               (7.5YR 5/6) masses of iron and manganese along
    Value—4 to 6
                                                               pores, few fine rounded prominent black (7.5YR
    Chroma—2 to 6
                                                               2.5/1) iron-manganese nodules throughout, and
C horizon:                                                     common fine distinct irregular light brownish gray
   Hue—10YR                                                    (2.5Y 6/2) iron depletions along pores; slightly
   Value—4 to 7                                                acid; clear smooth boundary.
   Chroma—2 to 8                                            BCt—52 to 67 inches; light olive brown (2.5Y 5/3) silt
                                                               loam; weak coarse subangular blocky structure;
                                                               friable; few very fine roots; few distinct dark
Buckhart Series                                                grayish brown (10YR 4/2) clay films in root
                                                               channels and/or pores; common fine irregular
Taxonomic classification: Fine-silty, mixed,
                                                               prominent strong brown (7.5YR 5/6) masses of
   superactive, mesic Oxyaquic Argiudolls
                                                               iron and manganese along pores, common fine
  Typical Pedon (Official Series Description)                  irregular light brownish gray (2.5Y 6/2) iron
                                                               depletions along pores, and few fine rounded
Buckhart silt loam, 2 to 5 percent slopes, at an
                                                               prominent black (7.5YR 2.5/1) iron-manganese
elevation of 603 feet; 360 feet west and 540 feet north
                                                               nodules throughout; neutral; gradual smooth
of the southeast corner of sec. 24, T. 14 N., R. 3 W.; in
                                                               boundary.
Christian County, Illinois; USGS Grove City
                                                            C—67 to 80 inches; yellowish brown (10YR 5/4) silt
topographic quadrangle; lat. 39 degrees 33 minutes 53
                                                               loam; massive; friable; common medium irregular
seconds N. and long. 89 degrees 22 minutes 06
                                                               distinct strong brown (7.5YR 5/6) masses of iron
seconds W., NAD 27:
                                                               and manganese throughout, common medium
Ap—0 to 8 inches; very dark grayish brown (10YR 3/2)           irregular prominent light brownish gray (2.5Y 6/2)
   silt loam, grayish brown (10YR 5/2) dry; moderate           iron depletions throughout, and few fine rounded
   medium granular structure; friable; few very fine           prominent black (7.5YR 2.5/1) iron-manganese
   roots; moderately acid; clear smooth boundary.              nodules throughout; neutral.
A—8 to 15 inches; very dark grayish brown (10YR 3/2)
                                                                         Range in Characteristics
   silt loam, grayish brown (10YR 5/2) dry; moderate
   fine subangular blocky structure parting to              Thickness of the loess: More than 80 inches
   moderate medium granular; friable; few very fine         Thickness of the mollic epipedon: 10 to 20 inches
   roots; moderately acid; clear smooth boundary.           Depth to the base of the argillic horizon: 40 to 55
Bt1—15 to 26 inches; dark yellowish brown (10YR 4/4)            inches
   silty clay loam; moderate medium subangular              Depth to carbonates (if they occur): More than 40
   blocky structure parting to moderate medium                  inches
   granular; friable; few very fine roots; many distinct
                                                            Ap and A horizons:
   brown (10YR 4/3) clay films on faces of peds and
                                                                Hue—10YR
   few distinct very dark grayish brown (10YR 3/2)
                                                                Value—2 or 3
   organic coatings in root channels and/or pores;
                                                                Chroma—1 to 3
   slightly acid; clear smooth boundary.
                                                                Texture—silt loam or silty clay loam
Bt2—26 to 37 inches; dark yellowish brown (10YR 4/4)
   silty clay loam; moderate medium subangular              Bt or Btg horizon:
   blocky structure; friable; few very fine roots; many         Hue—10YR or 2.5Y
   distinct dark grayish brown (10YR 4/2) clay films            Value—4 to 6
   on faces of peds; few fine irregular prominent               Chroma—2 to 6
34                                                                                                  Soil Survey of




     Texture—silty clay loam or silt loam                 Hazard of corrosion: Moderate for steel and moderate
     Reaction—moderately acid to neutral                      for concrete
                                                          Surface runoff class: Low
BC or BCg horizon:
                                                          Susceptibility to water erosion: Slight
   Hue—10YR or 2.5Y
                                                          Susceptibility to wind erosion: Slight
   Value—5 or 6
   Chroma—2 to 4                                                          Interpretive Groups
   Texture—silt loam or silty clay loam
                                                          Land capability classification: 1
   Reaction—neutral or slightly alkaline
                                                          Prime farmland status: Prime farmland
C or Cg horizon:                                          Hydric soil status: Not hydric
    Hue—10YR or 2.5Y
    Value—5 or 6
    Chroma—2 to 6                                         Burkhardt Series
    Reaction—neutral to moderately alkaline
                                                          Taxonomic classification: Sandy, mixed, mesic Typic
                                                             Hapludolls

705A—Buckhart silt loam, 0 to 2 percent                                      Typical Pedon
   slopes                                                 Burkhardt sandy loam, in an area of Burkhardt-Saude
                       Setting                            complex, 0 to 2 percent slopes; 58 feet west and 602
                                                          feet north of the southeast corner of sec. 33, T. 21 N.,
Landform: Knolls on ground moraines
                                                          R. 2 E.; in Rock Island County, Illinois; USGS
Position on the landform: Summits
                                                          Comanche topographic quadrangle; lat. 41 degrees 51
                    Composition                           minutes 55 seconds N. and long. 90 degrees 15
                                                          minutes 55 seconds W., NAD 27:
Buckhart and similar soils: 93 percent
Dissimilar soils: 7 percent                               A1—0 to 7 inches; very dark gray (10YR 3/1) and very
                                                             dark grayish brown (10YR 3/2) sandy loam;
                Minor Components
                                                             moderate fine and medium granular structure;
Similar soils:                                               very friable; moderately acid; clear smooth
• Soils that have a seasonal high water table at a           boundary.
depth of less than 2 feet                                 A2—7 to 13 inches; very dark gray (10YR 3/1) and
• Soils that have a seasonal high water table at a           very dark grayish brown (10YR 3/2) sandy loam;
depth of more than 3.5 feet                                  moderate medium subangular blocky structure
                                                             parting to moderate fine and medium granular;
Dissimilar soils:
                                                             very friable; moderately acid; clear smooth
• The poorly drained Sable soils on toeslopes
                                                             boundary.
• The poorly drained Denny soils in depressions
                                                          Bw—13 to 20 inches; brown (10YR 4/3), dark brown
Properties and Qualities of the Buckhart Soil                (10YR 3/3), and very dark gray (10YR 3/1) sandy
                                                             loam; moderate medium and coarse subangular
Parent material: Loess
                                                             blocky structure; very friable; moderately acid;
Drainage class: Moderately well drained
                                                             clear smooth boundary.
Slowest permeability within a depth of 40 inches:
                                                          2BC—20 to 24 inches; dark yellowish brown (10YR
    Moderate
                                                             4/4), dark brown (10YR 3/3), and brown (10YR
Permeability below a depth of 60 inches: Moderate
                                                             4/3) gravelly loamy sand; weak coarse subangular
Depth to restrictive feature: More than 80 inches
                                                             blocky structure; very friable; moderately acid;
Available water capacity to a depth of 60 inches: About
                                                             gradual smooth boundary.
    12.2 inches
                                                          2C—24 to 60 inches; yellowish brown (10YR 5/4) and
Content of organic matter in the surface layer: 3 to 4
                                                             dark brown (10YR 3/3) medium and coarse sand
    percent
                                                             and fine gravel; single grain; moderately acid.
Shrink-swell potential: Moderate
Depth and months of the highest apparent seasonal                      Range in Characteristics
    high water table: 2 feet, February to April
                                                          Thickness of the solum: 10 to 20 inches
Flooding: None
Accelerated erosion: None or slight                       Ap or A horizon:
Potential for frost action: High                              Hue—7.5YR or 10YR
Rock Island County, Illinois                                                                                       35




    Value—2 or 3                                          Content of organic matter in the surface layer: 2 to 3
    Chroma—1 to 3                                             percent
    Texture—sandy loam, loam, or gravelly sandy           Shrink-swell potential: Low
      loam                                                Flooding: None
                                                          Accelerated erosion: None or slight
Bw or Bt horizon:
                                                          Potential for frost action: Low
   Hue—7.5YR or 10YR
                                                          Hazard of corrosion: Low for steel and high for
   Value—3 or 4
                                                              concrete
   Chroma—2 to 4
                                                          Surface runoff class: Very low
   Texture—sandy loam, loam, gravelly sandy loam,
                                                          Susceptibility to water erosion: Slight
      or gravelly loam
                                                          Susceptibility to wind erosion: Moderately high
2Bt or 2BC horizon (if it occurs):
                                                            Properties and Qualities of the Saude Soil
    Hue—7.5YR or 10YR
    Value—3 or 4                                          Parent material: Outwash
    Chroma—4 to 6                                         Drainage class: Well drained
    Texture—sand, coarse sand, loamy sand, or             Slowest permeability within a depth of 40 inches:
       loamy coarse sand or the gravelly analogs of           Moderate
       these textures                                     Permeability below a depth of 60 inches: Very rapid
                                                          Depth to restrictive feature: More than 80 inches
2C horizon:
                                                          Available water capacity to a depth of 60 inches: About
    Hue—7.5YR or 10YR
                                                              6.7 inches
    Value—4 to 6
                                                          Content of organic matter in the surface layer: 3 to 4
    Chroma—4 to 6
                                                              percent
    Texture—stratified sand, coarse sand, gravelly
                                                          Shrink-swell potential: Low
      sand, or gravelly coarse sand
                                                          Flooding: None
                                                          Accelerated erosion: None or slight
                                                          Potential for frost action: Moderate
961A—Burkhardt-Saude complex, 0 to 2                      Hazard of corrosion: Low for steel and moderate for
   percent slopes                                             concrete
                                                          Surface runoff class: Low
                        Setting
                                                          Susceptibility to water erosion: Slight
Landform: Outwash plains                                  Susceptibility to wind erosion: Slight
Position on the landform: Summits
                                                                          Interpretive Groups
                    Composition                           Land capability classification: Burkhardt—2s; Saude—
                                                              2s
Burkhardt and similar soils: 50 percent
                                                          Prime farmland status: Prime farmland
Saude and similar soils: 50 percent
                                                          Hydric soil status: Burkhardt—not hydric; Saude—not
                                                              hydric
                Minor Components
Similar soils:
• Soils that have less gravel in the lower part           Calco Series
• Soils that are underlain by limestone bedrock within
                                                          Taxonomic classification: Fine-silty, mixed,
a depth of 60 inches
                                                             superactive, calcareous, mesic Cumulic
                                                             Endoaquolls
Properties and Qualities of the Burkhardt Soil
                                                                             Typical Pedon
Parent material: Outwash
Drainage class: Somewhat excessively drained              Calco silty clay loam, 0 to 2 percent slopes, frequently
Slowest permeability within a depth of 40 inches:         flooded; 1,100 feet east and 2,600 feet south of the
    Moderately rapid                                      northwest corner of sec. 19, T. 19 N., R. 4 E.; in
Permeability below a depth of 60 inches: Rapid            Whiteside County, Illinois; USGS Spring Hill
Depth to restrictive feature: More than 80 inches         topographic quadrangle; lat. 41 degrees 37 minutes 14
Available water capacity to a depth of 60 inches: About   seconds N. and long. 90 degrees 05 minutes 22
    4.1 inches                                            seconds W., NAD 27:
36                                                                                                   Soil Survey of




A1—0 to 17 inches; black (10YR 2/1) silty clay loam,                            Composition
   very dark gray (10YR 3/1) dry; moderate medium
                                                            Calco and similar soils: 99 percent
   granular structure; friable; few snail-shell
                                                            Dissimilar soils: 1 percent
   fragments; slightly effervescent; slightly alkaline;
   gradual smooth boundary.                                                 Minor Components
A2—17 to 30 inches; black (10YR 2/1) silty clay loam,
                                                            Similar soils:
   very dark gray (10YR 3/1) dry; moderate medium
                                                            • Soils that are not calcareous
   and fine subangular blocky structure; friable; few
                                                            • Soils that have a surface layer less than 24 inches
   snail-shell fragments; slightly effervescent; slightly
                                                            thick
   alkaline; gradual smooth boundary.
                                                            • Soils that contain less silt and more sand
A3—30 to 37 inches; black (10YR 2/1) silty clay loam,
                                                            throughout
   very dark gray (10YR 3/1) dry; weak medium and
                                                            • Soils that contain less clay throughout
   fine subangular blocky structure; friable; few snail-
   shell fragments; violently effervescent; slightly        Dissimilar soils:
   alkaline; gradual smooth boundary.                       • Moderately well drained soils on flood plains
Bg—37 to 49 inches; very dark gray (10YR 3/1) silty         • The poorly drained Millington and Otter soils on
   clay loam, gray (10YR 5/1) dry; weak medium              toeslopes
   subangular blocky structure; friable; few snail-shell
                                                              Properties and Qualities of the Calco Soil
   fragments; violently effervescent; slightly alkaline;
   clear smooth boundary.                                   Parent material: Alluvium
Cg—49 to 60 inches; dark gray (5Y 4/1) loam;                Drainage class: Poorly drained
   massive; friable; few thin lenses of sand; few snail-    Slowest permeability within a depth of 40 inches:
   shell fragments; violently effervescent; moderately          Moderate
   alkaline.                                                Permeability below a depth of 60 inches: Moderate
                                                            Depth to restrictive feature: More than 80 inches
             Range in Characteristics
                                                            Available water capacity to a depth of 60 inches: About
Thickness of the mollic epipedon: 30 to 50 inches               12.8 inches
Thickness of the solum: 40 to 60 inches                     Content of organic matter in the surface layer: 5 to 7
                                                                percent
Ap or A horizon:
                                                            Shrink-swell potential: Moderate
    Hue—10YR, 2.5Y, 5Y, or N
                                                            Depth and months of the highest apparent seasonal
    Value—2 or 3
                                                                high water table: At the surface, November to June
    Chroma—0 or 1
                                                            Ponding depth: 0.2 foot during wet periods
    Texture—silty clay loam or silt loam
                                                            Frequency and most likely period of flooding:
Bg horizon:                                                     Frequent, November to June
    Hue—10YR, 2.5Y, 5Y, or N                                Potential for frost action: High
    Value—3 to 6                                            Hazard of corrosion: High for steel and low for
    Chroma—0 or 1                                               concrete
    Texture—silty clay loam                                 Surface runoff class: Negligible
                                                            Susceptibility to water erosion: Slight
Cg horizon:
                                                            Susceptibility to wind erosion: Slight
    Hue—2.5Y, 5Y, or N
    Value—3 to 6                                                            Interpretive Groups
    Chroma—0 to 1
                                                            Land capability classification: 5w
    Texture—loam, clay loam, silt loam, or silty clay
                                                            Prime farmland status: Not prime farmland
      loam
                                                            Hydric soil status: Hydric

1400A—Calco silty clay loam, undrained,                     3400A—Calco silty clay loam, 0 to 2
   0 to 2 percent slopes, frequently                           percent slopes, frequently flooded
   flooded
                         Setting                                                     Setting
Landform: Flood plains                                      Landform: Flood plains
Rock Island County, Illinois                                                                                      37




                    Composition                                               Composition
Calco and similar soils: 85 percent                       Calco and similar soils: 85 percent
Dissimilar soils: 15 percent                              Dissimilar soils: 15 percent
                Minor Components                                          Minor Components
Similar soils:                                            Similar soils:
• Soils that are not calcareous                           • Soils that are not calcareous
• Soils that have a surface layer less than 24 inches     • Soils that have a surface layer less than 24 inches
thick                                                     thick
• Soils that contain less silt and more sand              • Soils that contain less silt and more sand
throughout                                                throughout
• Soils that contain less clay throughout                 • Soils that contain less clay throughout
Dissimilar soils:                                         Dissimilar soils:
• Moderately well drained soils on flood plains           • Moderately well drained soils on flood plains
• Well drained soils on low terrace footslopes
                                                            Properties and Qualities of the Calco Soil
  Properties and Qualities of the Calco Soil
                                                          Parent material: Alluvium
Parent material: Alluvium                                 Drainage class: Poorly drained
Drainage class: Poorly drained                            Slowest permeability within a depth of 40 inches:
Slowest permeability within a depth of 40 inches:             Moderate
    Moderate                                              Permeability below a depth of 60 inches: Moderate
Permeability below a depth of 60 inches: Moderate         Depth to restrictive feature: More than 80 inches
Depth to restrictive feature: More than 80 inches         Available water capacity to a depth of 60 inches: About
Available water capacity to a depth of 60 inches: About       12.7 inches
    12.7 inches                                           Content of organic matter in the surface layer: 5 to 7
Content of organic matter in the surface layer: 5 to 7        percent
    percent                                               Shrink-swell potential: Moderate
Shrink-swell potential: Moderate                          Depth and months of the highest apparent seasonal
Depth and months of the highest apparent seasonal             high water table: At the surface, January to May
    high water table: At the surface, January to May      Ponding depth: 0.2 foot during wet periods
Ponding depth: 0.2 foot during wet periods                Frequency and most likely period of flooding:
Frequency and most likely period of flooding:                 Occasional, November to June
    Frequent, November to June                            Potential for frost action: High
Potential for frost action: High                          Hazard of corrosion: High for steel and low for
Hazard of corrosion: High for steel and low for               concrete
    concrete                                              Surface runoff class: Negligible
Surface runoff class: Negligible                          Susceptibility to water erosion: Slight
Susceptibility to water erosion: Slight                   Susceptibility to wind erosion: Slight
Susceptibility to wind erosion: Slight
                                                                          Interpretive Groups
                Interpretive Groups
                                                          Land capability classification: 2w
Land capability classification: 2w                        Prime farmland status: Prime farmland where drained
Prime farmland status: Prime farmland where drained       Hydric soil status: Hydric
    and either protected from flooding or not
    frequently flooded during the growing season
Hydric soil status: Hydric                                Chute Series
                                                          Taxonomic classification: Mixed, mesic Typic
8400A—Calco silty clay loam, 0 to 2                          Udipsamments
   percent slopes, occasionally flooded                   Map unit in which this series occurs: 959G
                         Setting                                             Typical Pedon
Landform: Flood plains                                    Chute fine sand, 7 to 15 percent slopes, severely
38                                                                                                  Soil Survey of




eroded; 380 feet north and 2,000 feet west of the             few patchy prominent light gray (10YR 7/1) (dry)
southeast corner of sec. 17, T. 17 N., R. 6 E.; in            clay depletions on faces of peds; common fine
Bureau County, Illinois; USGS Mineral topographic             prominent irregular strong brown (7.5YR 5/6)
quadrangle; lat. 41 degrees 27 minutes 11 seconds N.          masses of iron oxide throughout; many fine
and long. 89 degrees 49 minutes 38 seconds W., NAD            prominent irregular light olive brown (2.5Y 5/4)
27:                                                           masses of iron oxide throughout; moderately acid;
                                                              clear wavy boundary.
A—0 to 4 inches; brown (10YR 5/3) fine sand, light
                                                          2Btg1—10 to 14 inches; dark grayish brown (10YR
  yellowish brown (10YR 6/4) dry; weak coarse
                                                              4/2) silty clay loam; weak medium subangular
  subangular blocky structure; very friable; few fine
                                                              blocky structure; firm; few fine roots; common
  roots; strongly effervescent; slightly alkaline;
                                                              continuous distinct very dark gray (10YR 3/1)
  gradual smooth boundary.
                                                              organo-clay films on faces of peds; common
C—4 to 60 inches; light yellowish brown (10YR 6/4)
                                                              discontinuous distinct dark gray (10YR 4/1) clay
  fine sand; single grain; loose; strongly
                                                              films on faces of peds; common fine prominent
  effervescent; slightly alkaline.
                                                              irregular strong brown (7.5YR 5/6) and many fine
             Range in Characteristics                         prominent irregular light olive brown (2.5Y 5/4)
                                                              masses of iron oxide throughout; moderately acid;
Thickness of the solum: Typically less than 15 inches
                                                              clear wavy boundary.
    (A and AC horizons)
                                                          2Btg2—14 to 19 inches; grayish brown (10YR 5/2) silty
A, Ap, or AC horizon (if it occurs):                          clay; weak coarse prismatic structure parting to
    Hue—10YR                                                  weak medium subangular blocky; firm; few fine
    Value—3 to 6                                              and medium roots; common discontinuous distinct
    Chroma—2 to 4                                             very dark gray (10YR 3/1) organo-clay films on
    Texture—loamy fine sand, fine sandy loam, fine            faces of peds; many fine prominent irregular
       sand, or sand                                          strong brown (7.5YR 5/6) masses of iron oxide
                                                              throughout; common fine faint irregular light
C horizon:
                                                              brownish gray (10YR 6/2) iron depletions
   Hue—10YR
                                                              throughout; moderately acid; clear wavy boundary.
   Value—5 or 6
                                                          2Btg3—19 to 26 inches; grayish brown (10YR 5/2) silty
   Chroma—3 to 6
                                                              clay loam; weak very coarse prismatic structure;
   Texture—fine sand, loamy fine sand, or sand
                                                              firm; few fine roots; few patchy distinct very dark
                                                              gray (10YR 3/1) organo-clay films on faces of
                                                              peds; common discontinuous distinct gray (10YR
Coatsburg Series                                              5/1) clay films on faces of peds; common fine and
                                                              medium prominent irregular strong brown (7.5YR
Taxonomic classification: Fine, smectitic, mesic Vertic
                                                              5/6) masses of iron oxide throughout; many fine
   Argiaquolls
                                                              faint irregular light brownish gray (10YR 6/2) iron
Map unit in which this series occurs: 944D2
                                                              depletions throughout; moderately acid; clear wavy
  Typical Pedon (Official Series Description)                 boundary.
                                                          2Btg4—26 to 38 inches; grayish brown (10YR 5/2) silty
Coatsburg silt loam, 5 to 10 percent slopes, eroded;
                                                              clay loam; weak very coarse prismatic structure;
2,550 feet east and 2,400 feet north of the southwest
                                                              firm; few very fine roots; few discontinuous distinct
corner of sec. 20, T. 2 N., R. 5 W.; in Adams County,
                                                              gray (10YR 5/1) clay films on faces of peds and in
Illinois; USGS Augusta topographic quadrangle; lat. 40
                                                              pores; common fine and medium prominent
degrees 08 minutes 31 seconds N. and long. 91
                                                              irregular black (2.5Y 2.5/1) masses of iron and
degrees 70 minutes 25 seconds W., NAD 27:
                                                              manganese oxide throughout; common fine and
Ap—0 to 6 inches; very dark gray (10YR 3/1) silt loam,        medium prominent irregular strong brown (7.5YR
   dark grayish brown (10YR 4/2) dry; moderate fine           5/6) masses of iron oxide throughout; many fine
   granular structure; friable; many fine and medium          and medium faint irregular light brownish gray
   roots; moderately acid; abrupt smooth boundary.            (10YR 6/2) iron depletions throughout; moderately
AB—6 to 10 inches; very dark gray (10YR 3/1) silty            acid; clear wavy boundary.
   clay loam, gray (10YR 5/1) dry; weak medium            2Btg5—38 to 45 inches; light brownish gray (10YR
   subangular blocky structure parting to moderate            6/2) silty clay loam; moderate very coarse
   fine subangular blocky; firm; common fine roots;           prismatic structure; firm; few discontinuous distinct
Rock Island County, Illinois                                                                                     39




    dark gray (10YR 4/1) clay films lining root             Texture—clay, clay loam, silty clay, or silty clay
    channels and pores; common discontinuous                  loam
    distinct grayish brown (10YR 5/2) clay films on         Reaction—strongly acid to slightly acid
    faces of peds; common patchy prominent light
                                                        2BCg or 2Cg horizon (if it occurs):
    gray (10YR 7/2) clay depletions on faces of peds;
                                                           Hue—10YR, 7.5YR, 2.5Y, 5Y, or N
    common medium prominent irregular brownish
                                                           Value—4 to 6
    yellow (10YR 6/8) masses of iron oxide
                                                           Chroma—0 to 8
    throughout; slightly acid; clear wavy boundary.
                                                           Texture—clay, clay loam, silty clay, silty clay loam,
2Btg6—45 to 62 inches; gray (10YR 6/1) silty clay
                                                             or loam
    loam; moderate very coarse prismatic structure;
                                                           Reaction—moderately acid to slightly alkaline
    firm; many continuous prominent light gray (10YR
    7/2) clay depletions on faces of peds; common
    continuous distinct gray (10YR 5/1) clay films on
    faces of peds; few medium prominent irregular       Coffeen Series
    black (2.5Y 2.5/1) masses of iron and manganese
                                                        Taxonomic classification: Coarse-silty, mixed,
    oxide throughout; common medium and coarse
                                                           superactive, mesic Fluvaquentic Hapludolls
    prominent irregular brownish yellow (10YR 6/6)
    masses of iron oxide throughout; slightly acid;                         Typical Pedon
    clear wavy boundary.
                                                        Coffeen silt loam, 0 to 2 percent slopes, frequently
2Btg7—62 to 70 inches; light brownish gray (10YR
                                                        flooded; 860 feet north and 1,740 feet west of the
    6/2) silty clay; weak very coarse prismatic
                                                        southeast corner of sec. 24, T. 20 N., R. 3 E.; in
    structure parting to moderate medium subangular
                                                        Whiteside County, Illinois; USGS Erie topographic
    blocky; very firm; few continuous distinct gray
                                                        quadrangle; lat. 41 degrees 42 minutes 09 seconds N.
    (10YR 6/1) clay films on faces of peds and in
                                                        and long. 90 degrees 05 minutes 56 seconds W., NAD
    pores; common fine prominent irregular black
                                                        27:
    (2.5Y 2.5/1) masses of iron and manganese oxide
    throughout; many medium prominent irregular         Ap—0 to 9 inches; very dark grayish brown (10YR 3/2)
    strong brown (7.5YR 5/6) masses of iron oxide          silt loam, grayish brown (10YR 5/2) dry; weak fine
    throughout; 2 percent pressure faces throughout;       granular structure; friable; neutral; abrupt smooth
    slightly acid; gradual wavy boundary.                  boundary.
2BCg—70 to 80 inches; gray (10YR 6/1) silty clay;       A—9 to 17 inches; very dark grayish brown (10YR 3/2)
    weak very coarse prismatic structure; firm;            silt loam, grayish brown (10YR 5/2) dry; weak
    common fine prominent irregular black (2.5Y            medium and fine subangular blocky structure
    2.5/1) masses of iron and manganese oxide              parting to moderate fine granular; friable; neutral;
    throughout; many coarse prominent irregular            clear smooth boundary.
    brownish yellow (10YR 6/6) masses of iron oxide     Bw1—17 to 24 inches; brown (10YR 4/3) silt loam;
    throughout; slightly acid.                             moderate medium subangular blocky structure;
                                                           friable; few faint very dark grayish brown (10YR
             Range in Characteristics
                                                           3/2) organic coatings on faces of peds; common
Thickness of the loess: Less than 20 inches                fine faint dark grayish brown (10YR 4/2) iron
Thickness of the mollic epipedon: 10 to 20 inches          depletions and common fine faint dark yellowish
Depth to the base of the argillic horizon: 50 to 80        brown (10YR 4/4) iron masses in the matrix;
    inches                                                 neutral; clear smooth boundary.
                                                        Bw2—24 to 33 inches; brown (10YR 4/3) silt loam;
Ap, A, or AB horizon:
                                                           moderate medium subangular blocky structure;
    Value—2 or 3
                                                           friable; common fine faint grayish brown (10YR
    Chroma—1 or 2
                                                           5/2) iron depletions and common fine faint brown
    Texture—silt loam, silty clay loam, or clay loam
                                                           (10YR 5/3) iron masses in the matrix; slightly
    Reaction—strongly acid to slightly alkaline (in
                                                           alkaline; clear smooth boundary.
       areas that have been limed)
                                                        BCg—33 to 46 inches; grayish brown (2.5Y 5/2) silt
Bt, Btg, 2Bt, or 2Btg horizon:                             loam; weak medium subangular blocky structure;
    Hue—10YR, 2.5Y, 5Y, or N                               friable; common fine prominent strong brown
    Value—3 to 6                                           (7.5YR 4/6) and dark yellowish brown (10YR 4/4)
    Chroma—0 to 2                                          iron masses in the matrix; common fine rounded
40                                                                                                 Soil Survey of




   iron-manganese concretions; slightly alkaline;         Slowest permeability within a depth of 40 inches:
   gradual smooth boundary.                                   Moderate
Cg—46 to 60 inches; grayish brown (2.5Y 5/2) and          Permeability below a depth of 60 inches: Moderate or
   brown (10YR 5/3) silt loam; massive; friable; few          moderately rapid
   fine rounded iron-manganese concretions; slightly      Depth to restrictive feature: More than 80 inches
   alkaline.                                              Available water capacity to a depth of 60 inches: About
                                                              11.5 inches
            Range in Characteristics
                                                          Content of organic matter in the surface layer: 2 to 3
Thickness of the mollic epipedon: 10 to 18 inches             percent
Thickness of the solum: 30 to 64 inches                   Shrink-swell potential: Low
                                                          Depth and months of the highest apparent seasonal
Ap or A horizon:
                                                              high water table: 1 foot, January to May
    Hue—10YR
                                                          Frequency and most likely period of flooding:
    Value—2 or 3
                                                              Frequent, November to June
    Chroma—1 to 3
                                                          Potential for frost action: High
Bw or Bg horizon:                                         Hazard of corrosion: High for steel and moderate for
   Hue—10YR or 2.5Y                                           concrete
   Value—4 to 6                                           Surface runoff class: Low
   Chroma—2 or 3                                          Susceptibility to water erosion: Slight
   Texture—silt loam; thin lenses of loam or sandy        Susceptibility to wind erosion: Slight
      loam in some pedons
                                                                          Interpretive Groups
C or Cg horizon:
                                                          Land capability classification: 2w
    Hue—10YR, 2.5Y, or 5Y
                                                          Prime farmland status: Prime farmland where
    Value—4 to 8
                                                              protected from flooding or not frequently flooded
    Chroma—1 to 3
                                                              during the growing season
    Texture—silt loam; strata of loam or sandy loam in
                                                          Hydric soil status: Not hydric
      some pedons

                                                          7428A—Coffeen silt loam, 0 to 2 percent
3428A—Coffeen silt loam, 0 to 2 percent
                                                             slopes, rarely flooded
   slopes, frequently flooded
                                                                                   Setting
                         Setting
                                                          Landform: Flood plains
Landform: Flood plains
                                                                              Composition
                    Composition
                                                          Coffeen and similar soils: 85 percent
Coffeen and similar soils: 90 percent
                                                          Dissimilar soils: 15 percent
Dissimilar soils: 10 percent
                                                                          Minor Components
                Minor Components
                                                          Similar soils:
Similar soils:                                            • Soils that have a thicker surface layer
• Soils that have a thicker surface layer                 • Soils that have a light-colored layer of overwash
• Soils that have a light-colored layer of overwash       material
material                                                  • Soils that are underlain by sand within a depth of 60
• Soils that are underlain by sand within a depth of 60   inches
inches
                                                          Dissimilar soils:
Dissimilar soils:                                         • The poorly drained Sawmill soils in the lower
• The well drained Raddle soils on flood plains           positions on flood plains
 Properties and Qualities of the Coffeen Soil              Properties and Qualities of the Coffeen Soil
Parent material: Alluvium                                 Parent material: Alluvium
Drainage class: Somewhat poorly drained                   Drainage class: Somewhat poorly drained
Rock Island County, Illinois                                                                                   41




Slowest permeability within a depth of 40 inches:              about 5 percent brown (7.5YR 4/4) loamy sand
    Moderate                                                   (Bt) consisting of several thin lamellae (total
Permeability below a depth of 60 inches: Moderate or           thickness less than 1 inch); weak fine and medium
    moderately rapid                                           subangular blocky structure; very friable; neutral;
Depth to restrictive feature: More than 80 inches              clear smooth boundary.
Available water capacity to a depth of 60 inches: About     E&Bt2—65 to 80 inches; about 90 percent yellowish
    11.5 inches                                                brown (10YR 5/4) sand (E); single grain; loose;
Content of organic matter in the surface layer: 2 to 3         about 10 percent brown (7.5YR 4/4) loamy sand
    percent                                                    (Bt) consisting of several thin lamellae (total
Shrink-swell potential: Low                                    thickness less than 2 inches); weak fine and
Depth and months of the highest apparent seasonal              medium subangular blocky structure; very friable;
    high water table: 1 foot, January to May                   neutral.
Frequency and most likely period of flooding: Rare,
                                                                         Range in Characteristics
    November to June
Potential for frost action: High                            Depth to first lamellae: 40 to 60 inches
Hazard of corrosion: High for steel and moderate for
                                                            Ap or A horizon:
    concrete
                                                                Hue—7.5YR or 10YR
Surface runoff class: Low
                                                                Value—2 to 4
Susceptibility to water erosion: Slight
                                                                Chroma—1 to 3
Susceptibility to wind erosion: Slight
                                                                Texture—sand or loamy sand
                Interpretive Groups
                                                            Bw horizon:
Land capability classification: 1                              Hue—7.5YR or 10YR
Prime farmland status: Prime farmland                          Value—4 to 6
Hydric soil status: Not hydric                                 Chroma—4 to 6
                                                               Texture—sand or loamy sand

Coloma Series                                               E part of E&Bt horizon:
                                                                Hue—5YR, 7.5YR, or 10YR
Taxonomic classification: Mixed, mesic Lamellic                 Value—4 to 7
   Udipsamments                                                 Chroma—3 to 6
                                                                Texture—sand, loamy sand, or sandy loam
                   Typical Pedon
                                                            Bt part of E&Bt horizon:
Coloma sand, 1 to 7 percent slopes; 1,500 feet east
                                                                Hue—5YR, 7.5YR, or 10YR
and 1,800 feet south of the northwest corner of sec.
                                                                Value—3 to 5
20, T. 14 N., R. 5 W.; in Mercer County, Illinois; USGS
                                                                Chroma—3 to 6
Joy topographic quadrangle; lat. 41 degrees 11
                                                                Texture—sandy loam, loamy sand, or sand
minutes 49 seconds N. and long. 90 degrees 59
minutes 23 seconds W., NAD 27:                              C horizon (if it occurs):
                                                               Hue—5YR, 7.5YR, or 10YR
Ap—0 to 9 inches; dark grayish brown (10YR 4/2)
                                                               Value—4 to 7
   sand, light grayish brown (10YR 6/2) dry; weak
                                                               Chroma—3 to 6
   medium granular structure; very friable; neutral;
                                                               Texture—sand
   clear wavy boundary.
Bw1—9 to 16 inches; brown (10YR 4/3) sand; single
   grain; loose; neutral; gradual wavy boundary.            689B—Coloma sand, 1 to 7 percent
Bw2—16 to 29 inches; dark yellowish brown (10YR                slopes
   4/4) sand; single grain; loose; slightly acid; gradual
                                                                                    Setting
   wavy boundary.
Bw3—29 to 50 inches; yellowish brown (10YR 5/4)             Landform: Dunes
   sand; single grain; loose; slightly acid; abrupt         Position on the landform: Shoulders
   smooth boundary.
                                                                                Composition
E&Bt1—50 to 65 inches; about 95 percent yellowish
   brown (10YR 5/4) sand (E); single grain; loose;          Coloma and similar soils: 100 percent
42                                                                                                   Soil Survey of




                Minor Components                            Slowest permeability within a depth of 40 inches:
                                                                Moderately rapid
Similar soils:
                                                            Permeability below a depth of 60 inches: Moderately
• Soils that have more clay in the upper part
                                                                rapid or rapid
• Soils that have less textural banding in the lower part
                                                            Depth to restrictive feature: More than 80 inches
• Soils that have a darker surface layer
                                                            Available water capacity to a depth of 60 inches: About
 Properties and Qualities of the Coloma Soil                    4.1 inches
                                                            Content of organic matter in the surface layer: 0.5 to
Parent material: Eolian sands
                                                                2.0 percent
Drainage class: Excessively drained
                                                            Shrink-swell potential: Low
Slowest permeability within a depth of 40 inches:
                                                            Flooding: None
    Moderately rapid
                                                            Accelerated erosion: None or slight
Permeability below a depth of 60 inches: Moderately
                                                            Potential for frost action: Low
    rapid or rapid
                                                            Hazard of corrosion: Low for steel and moderate for
Depth to restrictive feature: More than 80 inches
                                                                concrete
Available water capacity to a depth of 60 inches: About
                                                            Surface runoff class: Very low
    4.2 inches
                                                            Susceptibility to water erosion: Moderate
Content of organic matter in the surface layer: 0.5 to
                                                            Susceptibility to wind erosion: Very high
    2.0 percent
Shrink-swell potential: Low                                                Interpretive Groups
Flooding: None
                                                            Land capability classification: 6s
Accelerated erosion: None or slight
                                                            Prime farmland status: Not prime farmland
Potential for frost action: Low
                                                            Hydric soil status: Not hydric
Hazard of corrosion: Low for steel and moderate for
    concrete
Surface runoff class: Negligible                            Coyne Series
Susceptibility to water erosion: Slight
Susceptibility to wind erosion: Very high                   Taxonomic classification: Coarse-loamy, mixed, active,
                                                               mesic Typic Argiudolls
                Interpretive Groups
                                                              Typical Pedon (Official Series Description)
Land capability classification: 4s
Prime farmland status: Not prime farmland                   Coyne fine sandy loam, 0 to 2 percent slopes; 244 feet
Hydric soil status: Not hydric                              east and 847 feet south of the center of sec. 10, T. 20
                                                            N., R. 2 E.; in Rock Island County, Illinois; USGS
                                                            Cordova topographic quadrangle; lat. 41 degrees 44
689D—Coloma sand, 7 to 15 percent                           minutes 04 seconds N. and long. 90 degrees 15
   slopes                                                   minutes 21 seconds W., NAD 27:
                        Setting
                                                            Ap—0 to 9 inches; very dark gray (10YR 3/1) fine
Landform: Dunes                                                sandy loam, gray (10YR 5/1) dry; weak coarse
Position on the landform: Shoulders                            subangular blocky structure parting to moderate
                                                               very fine and fine granular; very friable; slightly
                    Composition
                                                               acid; abrupt smooth boundary.
Coloma and similar soils: 100 percent                       A1—9 to 13 inches; black (10YR 2/1) fine sandy loam,
                                                               dark gray (10YR 4/1) dry; weak coarse subangular
                Minor Components
                                                               blocky structure parting to moderate very fine and
Similar soils:                                                 fine granular; very friable; slightly acid; clear
• Soils that have more clay in the upper part                  smooth boundary.
• Soils that have less textural banding in the lower part   A2—13 to 23 inches; very dark gray (10YR 3/1) and
• Soils that have a darker surface layer                       very dark grayish brown (10YR 3/2) fine sandy
                                                               loam, gray (10YR 5/1) and grayish brown (10YR
 Properties and Qualities of the Coloma Soil
                                                               5/2) dry; moderate fine granular structure; very
Parent material: Eolian sands                                  friable; slightly acid; clear smooth boundary.
Drainage class: Excessively drained                         BA—23 to 28 inches; intermingled very dark grayish
Rock Island County, Illinois                                                                                 43




    brown (10YR 3/2), dark brown (10YR 3/3), and               clay loam, loam, silty clay loam, or silt
    dark grayish brown (10YR 4/2) fine sandy loam;             loam
    weak coarse subangular blocky structure parting          Reaction—moderately acid to moderately alkaline
    to weak very fine and fine granular; very friable;
    moderately acid; clear smooth boundary.
Bw—28 to 42 inches; brown (7.5YR 4/4) fine sandy         764A—Coyne fine sandy loam, 0 to 2
    loam; weak coarse subangular blocky structure;          percent slopes
    very friable; few fine black (10YR 2/1) iron and
                                                                                Setting
    manganese concretions; moderately acid; clear
    smooth boundary.                                     Landform: Lake plains
2Bt1—42 to 52 inches; reddish brown (5YR 4/4) silty      Position on the landform: Summits
    clay loam; strong medium and coarse subangular
                                                                            Composition
    blocky structure; firm; many distinct dark reddish
    brown (5YR 3/3) clay films on faces of peds;         Coyne and similar soils: 95 percent
    moderately acid; abrupt smooth boundary.             Dissimilar soils: 5 percent
2Bt2—52 to 55 inches; reddish brown (5YR 4/4) loam;
                                                                         Minor Components
    strong medium and coarse subangular blocky
    structure; firm; many distinct dark reddish brown    Similar soils:
    (5YR 3/3) clay films on faces of peds; moderately    • Soils that have less sand and more clay in the
    acid; abrupt smooth boundary.                        underlying material
3C—55 to 60 inches; brown (7.5YR 4/4) sand and           • Soils that have less silt and clay and more sand in
    gravel; single grain; loose; moderately acid.        the upper part
                                                         • Soils that have a perched seasonal high water table
             Range in Characteristics                    within a depth of 60 inches
Thickness of the solum: 48 to 72 inches                  Dissimilar soils:
Depth to the argillic horizon: More than 40 inches       • Somewhat poorly drained soils on summits
A horizon:                                                 Properties and Qualities of the Coyne Soil
    Hue—10YR
                                                         Parent material: Lacustrine deposits
    Value—2 or 3
                                                         Drainage class: Well drained
    Chroma—1 to 3
                                                         Slowest permeability within a depth of 40 inches:
    Texture—loam, fine sandy loam, or loamy fine
                                                             Moderate
       sand
                                                         Permeability below a depth of 60 inches: Rapid to
    Reaction—moderately acid to neutral
                                                             moderately slow
Bw horizon:                                              Depth to restrictive feature: More than 80 inches
   Hue—7.5YR or 10YR                                     Available water capacity to a depth of 60 inches: About
   Value—4 or 5                                              9.6 inches
   Chroma—3 to 5                                         Content of organic matter in the surface layer: 2 to 4
   Texture—loam or fine sandy loam                           percent
   Reaction—moderately acid to neutral                   Shrink-swell potential: Moderate
                                                         Flooding: None
2Bt horizon:
                                                         Accelerated erosion: None or slight
    Hue—5YR or 2.5YR
                                                         Potential for frost action: Moderate
    Value—4 to 6
                                                         Hazard of corrosion: Moderate for steel and moderate
    Chroma—3 to 6
                                                             for concrete
    Texture—loam, silt loam, silty clay loam, or silty
                                                         Surface runoff class: Low
      clay
                                                         Susceptibility to water erosion: Slight
    Reaction—moderately acid to neutral
                                                         Susceptibility to wind erosion: Moderately high
3C horizon:
                                                                        Interpretive Groups
    Hue—7.5YR or 10YR
    Value—3 to 6                                         Land capability classification: 2s
    Chroma—3 to 8                                        Prime farmland status: Prime farmland
    Texture—sand or sand and gravel with strata of       Hydric soil status: Not hydric
44                                                                                                 Soil Survey of




764C—Coyne fine sandy loam, 5 to 10                                          Typical Pedon
   percent slopes                                         Denny silt loam, 0 to 2 percent slopes, at an elevation
                                                          of 720 feet; 225 feet north and 1,680 feet east of the
                       Setting
                                                          southwest corner of sec. 25, T. 7 N., R. 3 W.; in
Landform: Lake plains                                     McDonough County, Illinois; USGS Good Hope
Position on the landform: Shoulders                       topographic quadrangle; lat. 40 degrees 33 minutes 31
                                                          seconds N. and long. 90 degrees 41 minutes 14
                    Composition
                                                          seconds W., NAD 27:
Coyne and similar soils: 95 percent
Dissimilar soils: 5 percent                               Ap—0 to 8 inches; very dark gray (10YR 3/1) silt loam,
                                                              gray (10YR 5/1) dry; weak fine granular structure;
                Minor Components
                                                              very friable; few very fine roots throughout;
Similar soils:                                                moderately acid; abrupt smooth boundary.
• Soils that have less sand and more clay in the          Eg1—8 to 14 inches; dark grayish brown (10YR 4/2)
underlying material                                           silt loam, light brownish gray (10YR 6/2) dry; weak
• Soils that have less silt and clay and more sand in         thick platy structure parting to weak thin platy;
the upper part                                                very friable; few very fine roots throughout; few
• Soils that have a perched seasonal high water table         very fine vesicular pores throughout; few distinct
within a depth of 60 inches                                   very dark gray (10YR 3/1) organic coatings in root
                                                              channels; common faint grayish brown (10YR 5/2)
Dissimilar soils:
                                                              clay depletions on faces of peds; common fine
• Somewhat poorly drained soils on summits
                                                              distinct dark yellowish brown (10YR 3/6) masses
  Properties and Qualities of the Coyne Soil                  that have accumulated iron and manganese and
                                                              are throughout the horizon; few fine black (7.5YR
Parent material: Lacustrine deposits
                                                              2.5/1) iron and manganese concretions in the
Drainage class: Well drained
                                                              matrix; moderately acid; clear smooth boundary.
Slowest permeability within a depth of 40 inches:
                                                          Eg2—14 to 21 inches; grayish brown (10YR 5/2) silt
    Moderate
                                                              loam, light gray (10YR 7/2) dry; weak thick platy
Permeability below a depth of 60 inches: Rapid to
                                                              structure parting to moderate medium platy;
    moderately slow
                                                              friable; few very fine roots throughout; few fine
Depth to restrictive feature: More than 80 inches
                                                              tubular pores and few very fine vesicular pores
Available water capacity to a depth of 60 inches: About
                                                              throughout; few distinct very dark gray (10YR 3/1)
    9.6 inches
                                                              organic coatings in root channels; common fine
Content of organic matter in the surface layer: 2 to 4
                                                              distinct dark brown (10YR 3/3) masses that have
    percent
                                                              accumulated iron and manganese and are
Shrink-swell potential: Moderate
                                                              throughout the horizon; common fine black (7.5YR
Flooding: None
                                                              2.5/1) iron and manganese concretions in the
Accelerated erosion: None or slight
                                                              matrix; moderately acid; abrupt smooth boundary.
Potential for frost action: Moderate
                                                          Btg1—21 to 29 inches; grayish brown (10YR 5/2) silty
Hazard of corrosion: Moderate for steel and moderate
                                                              clay loam; moderate fine and medium subangular
    for concrete
                                                              blocky structure; firm; few very fine roots between
Surface runoff class: Medium
                                                              peds; common distinct dark grayish brown (10YR
Susceptibility to water erosion: Moderate
                                                              4/2) clay films on faces of peds; few distinct very
Susceptibility to wind erosion: Moderately high
                                                              dark gray (10YR 3/1) organic coatings in root
                Interpretive Groups                           channels; many fine distinct dark yellowish brown
                                                              (10YR 4/6) and common fine faint yellowish brown
Land capability classification: 3e
                                                              (10YR 5/4) masses that have accumulated iron
Prime farmland status: Not prime farmland
                                                              and manganese and are throughout the horizon;
Hydric soil status: Not hydric
                                                              common fine black (7.5YR 2.5/1) iron and
                                                              manganese concretions in the matrix; moderately
Denny Series                                                  acid; clear smooth boundary.
                                                          Btg2—29 to 38 inches; grayish brown (10YR 5/2) silty
Taxonomic classification: Fine, smectitic, mesic Mollic       clay loam; moderate medium prismatic structure
   Albaqualfs                                                 parting to moderate medium subangular blocky;
Rock Island County, Illinois                                                                                  45




    firm; few very fine roots between peds; common            Chroma—1 or 2
    faint dark grayish brown (10YR 4/2) clay films on         Texture—silt loam
    faces of peds; few distinct very dark gray (10YR
                                                          Eg horizon:
    3/1) organic coatings in root channels; many fine
                                                              Hue—10YR or 2.5Y
    distinct dark yellowish brown (10YR 4/6) and
                                                              Value—4 to 6
    common fine distinct yellowish brown (10YR 5/8)
                                                              Chroma—1 or 2
    masses that have accumulated iron and
                                                              Texture—silt loam
    manganese and are throughout the horizon;
    common fine black (7.5YR 2.5/1) iron and              Btg horizon:
    manganese concretions in the matrix; moderately           Hue—10YR, 2.5Y, or 5Y
    acid; gradual smooth boundary.                            Value—4 to 6
Btg3—38 to 46 inches; light brownish gray (2.5Y 6/2)          Chroma—1 or 2
    silty clay loam; moderate coarse prismatic                Texture—silty clay loam or silty clay
    structure parting to moderate coarse subangular
                                                          Cg horizon:
    blocky; firm; very few fine roots between peds;
                                                              Hue—10YR, 2.5Y, or 5Y
    common distinct dark grayish brown (10YR 4/2)
                                                              Value—4 to 6
    clay films on faces of peds; few distinct very dark
                                                              Chroma—1 or 2
    gray (10YR 3/1) organic coatings in root channels;
                                                              Texture—silt loam or silty clay loam
    many fine prominent dark yellowish brown (10YR
    4/6) and common fine prominent strong brown
    (7.5YR 5/6) masses that have accumulated iron
    and manganese and are throughout the horizon;         45A—Denny silt loam, 0 to 2 percent
    common fine black (7.5YR 2.5/1) iron and                 slopes
    manganese concretions in the matrix; moderately                               Setting
    acid; gradual wavy boundary.
                                                          Landform: Depressions
Cg1—46 to 63 inches; light brownish gray (2.5Y 6/2)
    silty clay loam; massive; firm; few very fine roots                       Composition
    between peds; few very fine vesicular pores
                                                          Denny and similar soils: 98 percent
    throughout; very few distinct very dark gray (10YR
                                                          Dissimilar soils: 2 percent
    3/1) organic coatings in root channels; many fine
    prominent dark yellowish brown (10YR 4/6) and
                                                                          Minor Components
    common fine prominent strong brown (7.5YR 5/6)
    masses that have accumulated iron and                 Similar soils:
    manganese and are throughout the horizon; few         • Soils that have a thicker surface layer
    medium black (7.5YR 2.5/1) iron and manganese         • Soils that have less clay in the subsoil
    concretions in the matrix; slightly acid; diffuse     • Soils that have a seasonal high water table below a
    wavy boundary.                                        depth of 1 foot
Cg2—63 to 80 inches; light brownish gray (2.5Y 6/2)
                                                          Dissimilar soils:
    silt loam; massive; firm; many very fine vesicular
                                                          • The moderately well drained Buckhart soils on
    pores throughout; very few distinct very dark gray
                                                          summits
    (10YR 3/1) organic coatings in root channels;
                                                          • The well drained Osco soils on summits
    many fine prominent dark yellowish brown (10YR
    4/6) and common fine prominent strong brown             Properties and Qualities of the Denny Soil
    (7.5YR 5/6) masses that have accumulated iron
                                                          Parent material: Loess
    and manganese and are throughout the horizon;
                                                          Drainage class: Poorly drained
    few medium black (7.5YR 2.5/1) iron and
                                                          Slowest permeability within a depth of 40 inches: Slow
    manganese concretions in the matrix; slightly acid.
                                                          Permeability below a depth of 60 inches: Moderately
             Range in Characteristics                         slow
                                                          Depth to restrictive feature: More than 80 inches
Depth to the base of the diagnostic horizon: 40 to 65
                                                          Available water capacity to a depth of 60 inches: About
   inches
                                                              11.6 inches
Ap or A horizon:                                          Content of organic matter in the surface layer: 3 to 4
    Hue—10YR                                                  percent
    Value—2 or 3                                          Shrink-swell potential: High
46                                                                                                      Soil Survey of




Depth and months of the highest apparent seasonal             films bridging sand grains; slightly acid; clear
    high water table: At the surface, January to May          smooth boundary.
Ponding depth: 0.5 foot during wet periods                  BC—36 to 47 inches; yellowish brown (10YR 5/6)
Flooding: None                                                sand; weak coarse prismatic structure; very
Potential for frost action: High                              friable; moderately acid; clear smooth boundary.
Hazard of corrosion: High for steel and moderate for        C—47 to 60 inches; yellowish brown (10YR 5/6) sand;
    concrete                                                  single grain; loose; strong brown (7.5YR 5/6)
Surface runoff class: Negligible                              bands 1/2 inch to 2 inches thick at depths of 52, 56,
Susceptibility to water erosion: Slight                       and 58 inches; moderately acid.
Susceptibility to wind erosion: Slight
                                                                         Range in Characteristics
                Interpretive Groups
                                                            Thickness of the mollic epipedon: 12 to 24 inches
Land capability classification: 3w
                                                            Ap or A horizon:
Prime farmland status: Prime farmland where drained
                                                                Hue—10YR
Hydric soil status: Hydric
                                                                Value—2 or 3
                                                                Chroma—1 to 3
Dickinson Series                                                Texture—fine sandy loam, sandy loam, or loam
                                                            Bw horizon:
Taxonomic classification: Coarse-loamy, mixed,
                                                               Hue—10YR
   superactive, mesic Typic Hapludolls
                                                               Value—3 to 5
                   Typical Pedon                               Chroma—2 to 4
                                                               Texture—sandy loam or fine sandy loam
Dickinson sandy loam, 0 to 2 percent slopes; 360 feet
north and 1,720 feet west of the center of sec. 17, T.      BC and/or C horizon:
17 N., R. 6 E.; in Bureau County, Illinois; USGS               Hue—7.5YR or 10YR
Mineral topographic quadrangle; lat. 41 degrees 27             Value—4 or 5
minutes 37 seconds N. and long. 89 degrees 50                  Chroma—3 to 6
minutes 09 seconds W., NAD 27:                                 Texture—loamy sand, sand, loamy fine sand, or
                                                                 fine sand
Ap—0 to 8 inches; very dark brown (10YR 2/2) sandy
   loam, dark grayish brown (10YR 4/2) dry; weak
   fine granular structure; very friable; few fine roots;   87A—Dickinson sandy loam, 0 to 2
   moderately acid; abrupt smooth boundary.                    percent slopes
A1—8 to 15 inches; very dark brown (10YR 2/2) sandy
   loam, dark grayish brown (10YR 4/2) dry; weak                                   Setting
   medium subangular blocky structure; very friable;
                                                            Landform: Outwash plains
   few fine roots; moderately acid; clear smooth
                                                            Position on the landform: Summits
   boundary.
A2—15 to 20 inches; very dark grayish brown (10YR                               Composition
   3/2) sandy loam, grayish brown (10YR 5/2) dry;
                                                            Dickinson and similar soils: 90 percent
   weak medium subangular blocky structure; very
                                                            Dissimilar soils: 10 percent
   friable; few fine roots; common very dark brown
   (10YR 2/2) organic coatings on faces of peds;                            Minor Components
   slightly acid; clear smooth boundary.
                                                            Similar soils:
Bw—20 to 31 inches; brown (10YR 4/3) sandy loam;
                                                            • Soils that have a thinner surface layer
   weak medium prismatic structure parting to weak
                                                            • Soils that have more sand and gravel
   medium subangular blocky; very friable; few fine
                                                            • Soils that have more clay
   roots; many distinct dark brown (10YR 3/3)
   organic coatings on faces of peds; slightly acid;        Dissimilar soils:
   clear smooth boundary.                                   • The somewhat poorly drained Hoopeston soils on
Bt—31 to 36 inches; yellowish brown (10YR 5/6)              footslopes
   loamy sand; weak medium prismatic structure
                                                            Properties and Qualities of the Dickinson Soil
   parting to weak medium subangular blocky; very
   friable; common distinct brown (10YR 4/3) clay           Parent material: Eolian sands over outwash
Rock Island County, Illinois                                                                                       47




Drainage class: Well drained                              Content of organic matter in the surface layer: 1 to 2
Slowest permeability within a depth of 40 inches:             percent
    Moderately rapid                                      Shrink-swell potential: Low
Permeability below a depth of 60 inches: Rapid            Flooding: None
Depth to restrictive feature: More than 80 inches         Accelerated erosion: The surface layer has been
Available water capacity to a depth of 60 inches: About       thinned by erosion.
    5.5 inches                                            Potential for frost action: Moderate
Content of organic matter in the surface layer: 1 to 2    Hazard of corrosion: Low for steel and moderate for
    percent                                                   concrete
Shrink-swell potential: Low                               Surface runoff class: Low
Flooding: None                                            Susceptibility to water erosion: Moderate
Accelerated erosion: None or slight                       Susceptibility to wind erosion: Moderately high
Potential for frost action: Moderate
                                                                          Interpretive Groups
Hazard of corrosion: Low for steel and moderate for
    concrete                                              Land capability classification: 3e
Surface runoff class: Very low                            Prime farmland status: Prime farmland
Susceptibility to water erosion: Slight                   Hydric soil status: Not hydric
Susceptibility to wind erosion: Moderately high
                Interpretive Groups
                                                          Dorchester Series
Land capability classification: 2s
Prime farmland status: Prime farmland                     Taxonomic classification: Fine-silty, mixed,
Hydric soil status: Not hydric                               superactive, calcareous, mesic Typic Udifluvents
                                                                              Typical Pedon
87C2—Dickinson sandy loam, 5 to 10                        Dorchester silt loam, 0 to 2 percent slopes; 1,600 feet
   percent slopes, eroded                                 east and 1,650 feet south of the northwest corner of
                                                          sec. 36, T. 10 N., R. 6 E.; in Peoria County, Illinois;
                        Setting
                                                          USGS Oak Hill topographic quadrangle; lat. 40
Landform: Dunes                                           degrees 48 minutes 31 seconds N. and long. 89
Position on the landform: Backslopes                      degrees 46 minutes 11 seconds W., NAD 27:
                    Composition                           Ap—0 to 9 inches; dark grayish brown (10YR 4/2) silt
                                                             loam, light gray (10YR 6/1) dry; weak medium
Dickinson and similar soils: 95 percent
                                                             platy structure parting to weak very fine
Dissimilar soils: 5 percent
                                                             subangular blocky; friable; few very fine roots; few
                Minor Components                             faint very dark grayish brown (10YR 3/2) organic
                                                             stains on faces of peds; slightly effervescent;
Similar soils:
                                                             slightly alkaline; abrupt smooth boundary.
• Soils that have a thinner surface layer
                                                          C—9 to 32 inches; stratified dark grayish brown (10YR
• Soils that have more sand and gravel
                                                             4/2), grayish brown (10YR 5/2), brown (10YR 5/3),
• Soils that have more clay
                                                             very dark gray (10YR 3/1), and very dark grayish
Dissimilar soils:                                            brown (10YR 3/2) silt loam; few thin strata of loam;
• The somewhat poorly drained Hoopeston soils on             massive with moderate thin bedding planes
footslopes                                                   resulting from stratification; friable; few very fine
                                                             roots; slightly effervescent; slightly alkaline; abrupt
Properties and Qualities of the Dickinson Soil
                                                             smooth boundary.
Parent material: Eolian sands                             2Ab1—32 to 43 inches; black (10YR 2/1) silt loam;
Drainage class: Well drained                                 weak fine subangular blocky structure parting to
Slowest permeability within a depth of 40 inches:            weak very fine granular; friable; slightly alkaline;
    Moderately rapid                                         gradual smooth boundary.
Permeability below a depth of 60 inches: Rapid            2Ab2—43 to 60 inches; very dark gray (10YR 3/1) silt
Depth to restrictive feature: More than 80 inches            loam; moderate fine subangular blocky structure;
Available water capacity to a depth of 60 inches: About      friable; many faint black (10YR 2/1) organic stains
    5.4 inches                                               on faces of peds; few fine distinct brown (10YR
48                                                                                                    Soil Survey of




     4/3) redoximorphic features below a depth of 48       Slowest permeability within a depth of 40 inches:
     inches; slightly alkaline.                                Moderate
                                                           Permeability below a depth of 60 inches: Moderate
             Range in Characteristics
                                                           Depth to restrictive feature: More than 80 inches
Thickness of the solum: Less than 10 inches                Available water capacity to a depth of 60 inches: About
Depth to the 2Ab horizon: 20 to 45 inches                      13.1 inches
                                                           Content of organic matter in the surface layer: 0.5 to
Ap or A horizon:
                                                               2.0 percent
    Hue—10YR
                                                           Shrink-swell potential: Moderate
    Value—3 or 4
                                                           Depth and months of the highest apparent seasonal
    Chroma—2 or 3
                                                               high water table: 4 feet, February to April
    Texture—silt loam, loam, or silty clay loam
                                                           Frequency and most likely period of flooding:
C horizon:                                                     Frequent, November to June
   Hue—10YR                                                Potential for frost action: High
   Value—3 to 5                                            Hazard of corrosion: High for steel and low for concrete
   Chroma—2 or 3                                           Surface runoff class: Low
   Texture—silt loam; thin strata of loam in some          Susceptibility to water erosion: Slight
       pedons                                              Susceptibility to wind erosion: Slight
2Ab horizon:                                                               Interpretive Groups
   Hue—10YR
                                                           Land capability classification: 2w
   Value—2 or 3
                                                           Prime farmland status: Prime farmland where drained
   Chroma—1 to 3
                                                               and either protected from flooding or not
   Texture—clay loam, silt loam, or silty clay loam
                                                               frequently flooded during the growing season
                                                           Hydric soil status: Not hydric
3239A—Dorchester silt loam, 0 to 2
   percent slopes, frequently flooded                      7239A—Dorchester silt loam, 0 to 2
                         Setting                              percent slopes, rarely flooded
Landform: Flood plains                                                              Setting
                    Composition                            Landform: Flood plains
Dorchester and similar soils: 95 percent                                       Composition
Dissimilar soils: 5 percent
                                                           Dorchester and similar soils: 95 percent
                Minor Components                           Dissimilar soils: 5 percent
Similar soils:                                                             Minor Components
• Soils that are not calcareous
                                                           Similar soils:
• Soils that do not have a buried surface layer within a
                                                           • Soils that are not calcareous
depth of 60 inches
                                                           • Soils that do not have a buried surface layer within a
• Soils that contain more sand throughout
                                                           depth of 60 inches
• Soils that have a seasonal high water table within a
                                                           • Soils that contain more sand throughout
depth of 60 inches
                                                           • Soils that have a seasonal high water table within a
Dissimilar soils:                                          depth of 60 inches
• The somewhat poorly drained Orion soils on
                                                           Dissimilar soils:
footslopes
                                                           • The somewhat poorly drained Orion soils on
• The poorly drained Sawmill soils in the lower
                                                           footslopes
positions on flood plains
                                                           • The poorly drained Sawmill soils in the lower
                                                           positions on flood plains
         Properties and Qualities of the
                Dorchester Soil                                     Properties and Qualities of the
                                                                           Dorchester Soil
Parent material: Alluvium
Drainage class: Well drained                               Parent material: Alluvium
Rock Island County, Illinois                                                                                    49




Drainage class: Well drained                              BA—10 to 15 inches; dark brown (10YR 3/3) silty clay
Slowest permeability within a depth of 40 inches:            loam, brown (10YR 4/3) dry; moderate very fine
    Moderate                                                 and fine subangular blocky structure; friable;
Permeability below a depth of 60 inches: Moderate            common very fine roots; common faint very dark
Depth to restrictive feature: More than 80 inches            grayish brown (10YR 3/2) organic coatings on
Available water capacity to a depth of 60 inches: About      faces of peds; slightly acid; clear smooth
    13.1 inches                                              boundary.
Content of organic matter in the surface layer: 0.5 to    Bt1—15 to 22 inches; dark yellowish brown (10YR 4/4)
    2.0 percent                                              silty clay loam; moderate fine subangular blocky
Shrink-swell potential: Moderate                             structure; firm; few very fine roots; common
Depth and months of the highest apparent seasonal            distinct very dark grayish brown (10YR 3/2)
    high water table: 4 feet, February to April              organo-clay films on faces of peds; slightly acid;
Frequency and most likely period of flooding: Rare,          clear smooth boundary.
    November to June                                      Bt2—22 to 28 inches; dark yellowish brown (10YR 4/4)
Potential for frost action: High                             silty clay loam; moderate fine and medium
Hazard of corrosion: High for steel and low for              subangular blocky structure; firm; few very fine
    concrete                                                 roots; few distinct dark brown (10YR 3/3) organo-
Surface runoff class: Low                                    clay films on faces of peds; slightly acid; clear
Susceptibility to water erosion: Slight                      smooth boundary.
Susceptibility to wind erosion: Slight                    BCt—28 to 31 inches; yellowish brown (10YR 5/4) silty
                                                             clay loam; weak medium and coarse subangular
                Interpretive Groups
                                                             blocky structure; friable; few very fine roots; few
Land capability classification: 1                            faint brown (10YR 4/3) clay films on faces of peds;
Prime farmland status: Prime farmland                        few fine black (5YR 2.5/1) very weakly cemented
Hydric soil status: Not hydric                               concretions of manganese with diffuse boundaries
                                                             in ped interiors; neutral; clear smooth boundary.
                                                          C—31 to 60 inches; yellowish brown (10YR 5/4) silt
Elkhart Series                                               loam; massive; friable; few very fine roots in the
                                                             upper 10 inches; common fine prominent strong
Taxonomic classification: Fine-silty, mixed,                 brown (7.5YR 5/8) masses of iron in ped interiors;
   superactive, mesic Typic Argiudolls                       common medium distinct gray (10YR 6/1) iron
Taxadjunct features: The Elkhart soil in map unit            depletions along root channels and pores; strongly
   567C2 has a thinner dark surface layer than is            effervescent; moderately alkaline.
   defined as the range for the series. This soil is
                                                                       Range in Characteristics
   classified as a Mollic Hapludalf.
                                                          Thickness of the mollic epipedon: 10 to 20 inches
  Typical Pedon (Official Series Description)
                                                          Depth to the base of the argillic horizon: 20 to 40
Elkhart silt loam, 5 to 10 percent slopes, at an              inches
elevation of 570 feet; 2,060 feet south and 1,248 feet    Depth to carbonates: 20 to 40 inches
west of the northeast corner of sec. 32, T. 19 N., R. 3
                                                          Ap, A, or AB horizon:
W.; in Logan County, Illinois; USGS Broadwell
                                                              Hue—10YR
topographic quadrangle; lat. 40 degrees 03 minutes 26
                                                              Value—2 or 3
seconds N. and long. 89 degrees 26 minutes 58
                                                              Chroma—1 to 3
seconds W., NAD 27:
                                                              Texture—silt loam
Ap—0 to 8 inches; very dark grayish brown (10YR 3/2)          Reaction—moderately acid to slightly alkaline
   silt loam, dark grayish brown (10YR 4/2) dry; weak
                                                          BA or Bt horizon:
   fine and medium granular structure; friable;
                                                             Hue—7.5YR or 10YR
   common very fine roots; slightly acid; abrupt
                                                             Value—3 to 5
   smooth boundary.
                                                             Chroma—3 to 6
A—8 to 10 inches; very dark grayish brown (10YR 3/2)
                                                             Texture—silty clay loam or silt loam
   silt loam, dark grayish brown (10YR 4/2) dry;
                                                             Reaction—moderately acid to neutral
   moderate fine granular structure; friable; common
   very fine roots; slightly acid; clear smooth           BC horizon:
   boundary.                                                 Hue—7.5YR, 10YR, or 2.5Y
50                                                                                                   Soil Survey of




     Value—4 to 6                                         Potential for frost action: High
     Chroma—3 to 6                                        Hazard of corrosion: Moderate for steel and moderate
     Texture—silt loam or silty clay loam                     for concrete
     Reaction—slightly acid to moderately alkaline        Surface runoff class: Medium
                                                          Susceptibility to water erosion: Moderate
C horizon:
                                                          Susceptibility to wind erosion: Slight
   Hue—10YR, 2.5Y, or 5Y
   Value—4 to 6                                                           Interpretive Groups
   Chroma—1 to 6
                                                          Land capability classification: 3e
   Texture—silt or silt loam
                                                          Prime farmland status: Not prime farmland
   Reaction—slightly alkaline or moderately alkaline
                                                          Hydric soil status: Not hydric

567C2—Elkhart silt loam, 5 to 10 percent
   slopes, eroded                                         567D2—Elkhart silt loam, 10 to 18 percent
                                                             slopes, eroded
                        Setting
                                                                                  Setting
Landform: Ground moraines
Position on the landform: Backslopes and shoulders        Landform: Ground moraines
                                                          Position on the landform: Backslopes
                    Composition
                                                                              Composition
Elkhart and similar soils: 90 percent
Dissimilar soils: 10 percent                              Elkhart and similar soils: 97 percent
                                                          Dissimilar soils: 3 percent
                Minor Components
                                                                          Minor Components
Similar soils:
• Soils that have a lighter colored surface layer         Similar soils:
• Soils that are not calcareous within a depth of 40      • Soils that have a lighter colored surface layer
inches                                                    • Soils that are not calcareous within a depth of 40
• Soils that are underlain by clayey glacial till at a    inches
depth of more than 40 inches                              • Soils that are underlain by clayey glacial till at a
                                                          depth of more than 40 inches
Dissimilar soils:
• The somewhat poorly drained Radford soils on            Dissimilar soils:
toeslopes                                                 • The somewhat poorly drained Radford soils on
• The somewhat poorly drained Muscatune soils on          toeslopes
summits
                                                           Properties and Qualities of the Elkhart Soil
 Properties and Qualities of the Elkhart Soil
                                                          Parent material: Loess
Parent material: Loess                                    Drainage class: Well drained
Drainage class: Well drained                              Slowest permeability within a depth of 40 inches:
Slowest permeability within a depth of 40 inches:             Moderate
    Moderate                                              Permeability below a depth of 60 inches: Moderate
Permeability below a depth of 60 inches: Moderate         Depth to restrictive feature: More than 80 inches
Depth to restrictive feature: More than 80 inches         Available water capacity to a depth of 60 inches: About
Available water capacity to a depth of 60 inches: About       12.4 inches
    12.4 inches                                           Content of organic matter in the surface layer: 2 to 3
Content of organic matter in the surface layer: 1 to 3        percent
    percent                                               Shrink-swell potential: Moderate
Shrink-swell potential: Moderate                          Depth and months of the highest apparent seasonal
Depth and months of the highest apparent seasonal             high water table: 4 feet, February to April
    high water table: 4 feet, February to April           Flooding: None
Flooding: None                                            Accelerated erosion: The surface layer has been
Accelerated erosion: The surface layer has been               thinned by erosion.
    thinned by erosion.                                   Potential for frost action: High
Rock Island County, Illinois                                                                                51




Hazard of corrosion: Moderate for steel and moderate        gray (10YR 7/2) (dry) clay depletions on faces of
    for concrete                                            peds; few prominent dark brown (7.5YR 3/2)
Surface runoff class: Medium                                accumulations of iron-manganese on faces of
Susceptibility to water erosion: High                       peds; moderately acid; gradual wavy boundary.
Susceptibility to wind erosion: Slight                    BC—38 to 55 inches; yellowish brown (10YR 5/4) silt
                                                            loam; moderate medium and coarse subangular
                Interpretive Groups
                                                            blocky structure; friable; common faint dark
Land capability classification: 3e                          yellowish brown (10YR 4/4) clay films on faces of
Prime farmland status: Not prime farmland                   peds; common distinct light gray (10YR 7/2) (dry)
Hydric soil status: Not hydric                              clay depletions on faces of peds; few prominent
                                                            dark brown (7.5YR 3/2) accumulations of iron-
                                                            manganese on faces of peds; moderately acid;
Fayette Series                                              clear wavy boundary.
                                                          C—55 to 60 inches; yellowish brown (10YR 5/4) silt
Taxonomic classification: Fine-silty, mixed,                loam; massive; friable; few prominent dark brown
   superactive, mesic Typic Hapludalfs                      (7.5YR 3/2) concretions of iron and manganese
                                                            throughout the matrix; moderately acid.
                   Typical Pedon
                                                                        Range in Characteristics
Fayette silt loam, 10 to 18 percent slopes, eroded;
2,100 feet north and 1,700 feet west of the southeast     Thickness of the solum: 36 to 70 inches
corner of sec. 31, T. 12 N., R. 3 W.; in Warren County,   Depth to free carbonates: More than 40 inches
Illinois; USGS Rozetta topographic quadrangle; lat. 40
                                                          Ap or A horizon:
degrees 59 minutes 13 seconds N. and long. 90
                                                              Hue—10YR
degrees 46 minutes 18 seconds W., NAD 27:
                                                              Value—2 to 4
Ap—0 to 5 inches; mixed dark grayish brown (10YR              Chroma—1 to 3
   4/2) and yellowish brown (10YR 5/4) silt loam, light
                                                          E horizon (if it occurs):
   brownish gray (10YR 6/2) dry; moderate medium
                                                              Value—3 to 5
   granular structure; friable; common fine roots
                                                              Chroma—1 to 4
   throughout; moderately acid; clear smooth
   boundary.                                              Bt horizon:
EB—5 to 9 inches; mixed brown (10YR 5/3) and                  Hue—10YR
   yellowish brown (10YR 5/4) silt loam; weak                 Value—4 or 5
   medium platy structure parting to moderate fine            Chroma—3 to 6
   subangular blocky; friable; common fine roots
                                                          BC and C horizons:
   between peds; few faint dark yellowish brown
                                                             Hue—10YR
   (10YR 4/4) clay films on faces of peds; moderately
                                                             Value—4 or 5
   acid; clear smooth boundary.
                                                             Chroma—4 to 6
Bt1—9 to 13 inches; dark yellowish brown (10YR 4/4)
                                                             Texture—silt loam or silty clay loam
   silt loam; moderate fine and medium subangular
   blocky structure; friable; few fine roots between
   peds; common faint brown (10YR 4/3) clay films         280B—Fayette silt loam, 2 to 5 percent
   on faces of peds; moderately acid; clear smooth           slopes
   boundary.
                                                                                      Setting
Bt2—13 to 27 inches; yellowish brown (10YR 5/4) silty
   clay loam; moderate medium subangular blocky           Landform: Ground moraines
   structure; friable; few fine roots between peds;       Position on the landform: Summits and shoulders
   common faint dark yellowish brown (10YR 4/4)
                                                                               Composition
   clay films on faces of peds; moderately acid;
   gradual smooth boundary.                               Fayette and similar soils: 97 percent
Bt3—27 to 38 inches; yellowish brown (10YR 5/4) silty     Dissimilar soils: 3 percent
   clay loam; weak coarse prismatic structure parting
                                                                           Minor Components
   to moderate medium subangular blocky; friable;
   common faint dark yellowish brown (10YR 4/4)           Similar soils:
   clay films on faces of peds; common distinct light     • Soils that have a darker surface layer
52                                                                                                 Soil Survey of




• Soils that have a seasonal high water table within a    • Soils that have loamy or sandy layers within a depth
depth of 6 feet                                           of 60 inches
• Soils that are calcareous within a depth of 40 inches
                                                          Dissimilar soils:
• Soils that have loamy or sandy layers within a depth
                                                          • The somewhat poorly drained Atterberry and
of 60 inches
                                                          Stronghurst soils on summits
Dissimilar soils:
                                                           Properties and Qualities of the Fayette Soil
• The somewhat poorly drained Atterberry and
Stronghurst soils on summits                              Parent material: Loess
                                                          Drainage class: Well drained
 Properties and Qualities of the Fayette Soil
                                                          Slowest permeability within a depth of 40 inches:
Parent material: Loess                                        Moderate
Drainage class: Well drained                              Permeability below a depth of 60 inches: Moderate
Slowest permeability within a depth of 40 inches:         Depth to restrictive feature: More than 80 inches
    Moderate                                              Available water capacity to a depth of 60 inches: About
Permeability below a depth of 60 inches: Moderate             11.4 inches
Depth to restrictive feature: More than 80 inches         Content of organic matter in the surface layer: 1 to 2
Available water capacity to a depth of 60 inches: About       percent
    11.6 inches                                           Shrink-swell potential: Moderate
Content of organic matter in the surface layer: 1 to 3    Flooding: None
    percent                                               Accelerated erosion: The surface layer has been
Shrink-swell potential: Moderate                              thinned by erosion.
Flooding: None                                            Potential for frost action: High
Accelerated erosion: None or slight                       Hazard of corrosion: Moderate for steel and moderate
Potential for frost action: High                              for concrete
Hazard of corrosion: Moderate for steel and moderate      Surface runoff class: Low
    for concrete                                          Susceptibility to water erosion: Moderate
Surface runoff class: Low                                 Susceptibility to wind erosion: Slight
Susceptibility to water erosion: Moderate
                                                                          Interpretive Groups
Susceptibility to wind erosion: Slight
                                                          Land capability classification: 2e
                Interpretive Groups
                                                          Prime farmland status: Prime farmland
Land capability classification: 2e                        Hydric soil status: Not hydric
Prime farmland status: Prime farmland
Hydric soil status: Not hydric
                                                          280C2—Fayette silt loam, 5 to 10 percent
                                                             slopes, eroded
280B2—Fayette silt loam, 2 to 5 percent
   slopes, eroded                                                                Setting
                                                          Landform: Ground moraines
                       Setting
                                                          Position on the landform: Shoulders and backslopes
Landform: Ground moraines
                                                                              Composition
Position on the landform: Summits and shoulders
                                                          Fayette and similar soils: 95 percent
                    Composition
                                                          Dissimilar soils: 5 percent
Fayette and similar soils: 94 percent
                                                                          Minor Components
Dissimilar soils: 6 percent
                                                          Similar soils:
                Minor Components
                                                          • Soils that have a darker surface layer
Similar soils:                                            • Soils that have a seasonal high water table within a
• Soils that have a darker surface layer                  depth of 6 feet
• Soils that have a seasonal high water table within a    • Soils that are calcareous within a depth of 40 inches
depth of 6 feet                                           • Soils that have loamy or sandy layers within a depth
• Soils that are calcareous within a depth of 40 inches   of 60 inches
Rock Island County, Illinois                                                                                    53




Dissimilar soils:                                         underlain by paleosol till within a depth of 60 inches;
• The somewhat poorly drained Stronghurst soils on        on shoulders and backslopes
summits                                                   • The somewhat poorly drained Stronghurst soils on
                                                          summits
 Properties and Qualities of the Fayette Soil
                                                           Properties and Qualities of the Fayette Soil
Parent material: Loess
Drainage class: Well drained                              Parent material: Loess
Slowest permeability within a depth of 40 inches:         Drainage class: Well drained
    Moderate                                              Slowest permeability within a depth of 40 inches:
Permeability below a depth of 60 inches: Moderate             Moderate
Depth to restrictive feature: More than 80 inches         Permeability below a depth of 60 inches: Moderate
Available water capacity to a depth of 60 inches: About   Depth to restrictive feature: More than 80 inches
    11.4 inches                                           Available water capacity to a depth of 60 inches: About
Content of organic matter in the surface layer: 1 to 2        11.4 inches
    percent                                               Content of organic matter in the surface layer: 0.5 to
Shrink-swell potential: Moderate                              2.0 percent
Flooding: None                                            Shrink-swell potential: Moderate
Accelerated erosion: The surface layer has been           Flooding: None
    thinned by erosion.                                   Accelerated erosion: The surface layer is mostly
Potential for frost action: High                              subsoil material.
Hazard of corrosion: Moderate for steel and moderate      Potential for frost action: High
    for concrete                                          Hazard of corrosion: Moderate for steel and moderate
Surface runoff class: Medium                                  for concrete
Susceptibility to water erosion: High                     Surface runoff class: Medium
Susceptibility to wind erosion: Slight                    Susceptibility to water erosion: High
                                                          Susceptibility to wind erosion: Very slight
                Interpretive Groups
                                                                          Interpretive Groups
Land capability classification: 3e
                                                          Land capability classification: 4e
Prime farmland status: Not prime farmland
                                                          Prime farmland status: Not prime farmland
Hydric soil status: Not hydric
                                                          Hydric soil status: Not hydric


280C3—Fayette silty clay loam, 5 to 10                    3646L—Fluvaquents, loamy, 0 to 2
   percent slopes, severely eroded                           percent slopes, frequently flooded,
                                                             long duration
                        Setting
                                                                                   Setting
Landform: Ground moraines
Position on the landform: Backslopes and shoulders        Landform: Flood plains
                    Composition                                               Composition
Fayette and similar soils: 94 percent                     Fluvaquents and similar soils: 95 percent
Dissimilar soils: 6 percent                               Dissimilar soils: 5 percent
                Minor Components                                          Minor Components
Similar soils:                                            Similar soils:
• Soils that have a darker surface layer                  • Soils that have more sand
• Soils that have a seasonal high water table within a    • Soils that have more clay
depth of 6 feet
                                                          Dissimilar soils:
• Soils that are calcareous within a depth of 40 inches
                                                          • The somewhat poorly drained Hoopeston soils on
• Soils that have loamy or sandy layers within a depth
                                                          summits
of 60 inches
                                                           Properties and Qualities of the Fluvaquents
Dissimilar soils:
• Moderately well drained loess soils that are            Parent material: Alluvium
54                                                                                                  Soil Survey of




Drainage class: Poorly drained                               dark gray (10YR 3/1) organic coatings and
Slowest permeability within a depth of 40 inches:            common distinct gray (10YR 6/1) silt coatings on
    Moderate                                                 faces of peds; moderately acid; clear smooth
Permeability below a depth of 60 inches: Moderate            boundary.
Depth to restrictive feature: More than 80 inches         Bt1—17 to 29 inches; yellowish brown (10YR 5/4) silty
Available water capacity to a depth of 60 inches: About      clay loam; weak medium prismatic structure
    11.9 inches                                              parting to moderate fine and medium angular
Content of organic matter in the surface layer: 2 to 4       blocky; friable; common faint dark yellowish brown
    percent                                                  (10YR 4/4) clay films on faces of peds; common
Shrink-swell potential: Moderate                             distinct gray (10YR 6/1) silt coatings on faces of
Depth and months of the highest apparent seasonal            peds; strongly acid; gradual smooth boundary.
    high water table: At the surface all year             Bt2—29 to 38 inches; brown (10YR 5/3) silty clay
Ponding depth: 0.2 foot during wet periods                   loam; weak medium prismatic structure parting to
Frequency and most likely period of flooding:                moderate fine angular blocky; friable; common
    Frequent, November to June                               faint brown (10YR 4/3) clay films on faces of peds;
Potential for frost action: High                             many faint light gray (10YR 7/2) silt coatings on
Hazard of corrosion: Moderate for steel and low for          faces of peds; common medium distinct yellowish
    concrete                                                 brown (10YR 5/6) masses of iron; common
Surface runoff class: Negligible                             medium prominent light olive gray (5Y 6/2) iron
Susceptibility to water erosion: Slight                      depletions within peds; common prominent black
Susceptibility to wind erosion: Slight                       (7.5YR 2.5/1) manganese oxide stains; strongly
                                                             acid; gradual wavy boundary.
                Interpretive Groups                       Bt3—38 to 53 inches; brown (10YR 5/3) silty clay
                                                             loam; weak medium prismatic structure parting to
Land capability classification: 5w
                                                             moderate fine angular blocky; friable; common
Prime farmland status: Not prime farmland
                                                             faint brown (10YR 4/3) clay films on faces of peds;
Hydric soil status: Hydric
                                                             many distinct light gray (10YR 7/2) silt coatings on
                                                             faces of peds; common medium distinct yellowish
                                                             brown (10YR 5/6) masses of iron; common
Greenbush Series                                             medium prominent light olive gray (5Y 6/2) iron
                                                             depletions within peds; common prominent black
Taxonomic classification: Fine-silty, mixed,
                                                             (7.5YR 2.5/1) manganese oxide stains; strongly
   superactive, mesic Mollic Hapludalfs
                                                             acid; gradual wavy boundary.
  Typical Pedon (Official Series Description)             BCt—53 to 75 inches; brown (10YR 5/3) and light olive
                                                             gray (5Y 6/2) silt loam; weak medium and coarse
Greenbush silt loam, 2 to 5 percent slopes, at an
                                                             prismatic structure parting to weak fine and
elevation of 700 feet; 1,500 feet west and 1,500 feet
                                                             medium angular blocky; friable; few faint brown
north of the southeast corner of sec. 18, T. 8 N., R. 1
                                                             (10YR 4/3) clay films on faces of peds; few faint
W.; in Warren County, Illinois; USGS Greenbush
                                                             light gray (10YR 7/2) silt coatings on faces of
topographic quadrangle; lat. 40 degrees 40 minutes 40
                                                             peds; common medium distinct yellowish brown
seconds N. and long. 90 degrees 32 minutes 45
                                                             (10YR 5/6) masses of iron within peds; common
seconds W., NAD 27:
                                                             prominent black (7.5YR 2.5/1) manganese oxide
Ap—0 to 6 inches; very dark gray (10YR 3/1) silt loam,       stains; moderately acid; gradual wavy boundary.
   gray (10YR 5/1) dry; moderate fine granular            C—75 to 100 inches; yellowish brown (10YR 5/4) and
   structure; friable; slightly acid; abrupt smooth          light olive gray (5Y 6/2) silt loam; massive; friable;
   boundary.                                                 many medium distinct light brownish gray (10YR
E—6 to 10 inches; dark grayish brown (10YR 4/2) silt         6/2) iron depletions within peds; many prominent
   loam; weak thin platy structure; friable; common          black (7.5YR 2.5/1) manganese oxide stains;
   faint very dark gray (10YR 3/1) organic coatings          moderately acid.
   on faces of peds; moderately acid; abrupt smooth
                                                                       Range in Characteristics
   boundary.
BE—10 to 17 inches; brown (10YR 4/3) silt loam;           Depth to carbonates: More than 60 inches
   moderate medium platy structure parting to weak        Depth to the base of the argillic horizon: 36 to 70
   fine subangular blocky; friable; few distinct very        inches
Rock Island County, Illinois                                                                                  55




Ap or A horizon:                                          Depth and months of the highest apparent seasonal
    Hue—10YR                                                  high water table: 4 feet, February to April
    Value—2 or 3                                          Flooding: None
    Chroma—1 or 2                                         Accelerated erosion: None or slight
                                                          Potential for frost action: High
E horizon:
                                                          Hazard of corrosion: Moderate for steel and moderate
    Hue—10YR
                                                              for concrete
    Value—3 to 5
                                                          Surface runoff class: Low
    Chroma—2 or 3
                                                          Susceptibility to water erosion: Slight
Bt horizon:                                               Susceptibility to wind erosion: Slight
    Hue—10YR
                                                                          Interpretive Groups
    Value—4 or 5
    Chroma—3 to 6                                         Land capability classification: 1
    Texture—silty clay loam                               Prime farmland status: Prime farmland
                                                          Hydric soil status: Not hydric
C horizon:
   Hue—10YR or 2.5Y
   Value—4 to 6
   Chroma—2 to 6                                          675B—Greenbush silt loam, 2 to 5 percent
   Texture—silt loam                                         slopes
                                                                                  Setting
675A—Greenbush silt loam, 0 to 2 percent                  Landform: Ground moraines
   slopes                                                 Position on the landform: Summits and shoulders
                        Setting                                               Composition
Landform: Ground moraines                                 Greenbush and similar soils: 95 percent
Position on the landform: Summits                         Dissimilar soils: 5 percent
                    Composition                                           Minor Components
Greenbush and similar soils: 90 percent                   Similar soils:
Dissimilar soils: 10 percent                              • Soils that have a thicker surface layer
                                                          • Soils that have a lighter colored surface layer
                Minor Components
                                                          Dissimilar soils:
Similar soils:
                                                          • The somewhat poorly drained Atterberry soils on
• Soils that have a thicker surface layer
                                                          summits
• Soils that have a lighter colored surface layer
                                                          • The poorly drained Denny soils in depressions
Dissimilar soils:
                                                                   Properties and Qualities of the
• The somewhat poorly drained Atterberry soils on
                                                                          Greenbush Soil
summits
• The poorly drained Denny soils in depressions           Parent material: Loess
                                                          Drainage class: Well drained
         Properties and Qualities of the
                                                          Slowest permeability within a depth of 40 inches:
                Greenbush Soil
                                                              Moderate
Parent material: Loess                                    Permeability below a depth of 60 inches: Moderate
Drainage class: Well drained                              Depth to restrictive feature: More than 80 inches
Slowest permeability within a depth of 40 inches:         Available water capacity to a depth of 60 inches: About
    Moderate                                                  11.8 inches
Permeability below a depth of 60 inches: Moderate         Content of organic matter in the surface layer: 2 to 3
Depth to restrictive feature: More than 80 inches             percent
Available water capacity to a depth of 60 inches: About   Shrink-swell potential: Moderate
    11.6 inches                                           Depth and months of the highest apparent seasonal
Content of organic matter in the surface layer: 2 to 3        high water table: 4 feet, February to April
    percent                                               Flooding: None
Shrink-swell potential: Moderate                          Accelerated erosion: None or slight
56                                                                                                   Soil Survey of




Potential for frost action: High                               iron-manganese in the matrix; neutral; gradual
Hazard of corrosion: Moderate for steel and moderate           wavy boundary.
    for concrete                                           2Bt4—31 to 40 inches; dark yellowish brown (10YR
Surface runoff class: Low                                      4/4) clay loam; weak medium and coarse
Susceptibility to water erosion: Moderate                      subangular blocky structure; firm; few very fine
Susceptibility to wind erosion: Slight                         and fine roots between peds; common distinct
                                                               brown (7.5YR 4/4) clay films on faces of peds; few
                Interpretive Groups
                                                               fine rounded black (7.5YR 2.5/1) concretions of
Land capability classification: 2e                             iron-manganese in the matrix; 5 percent gravel;
Prime farmland status: Prime farmland                          neutral; clear smooth boundary.
Hydric soil status: Not hydric                             2BC—40 to 54 inches; brown (7.5YR 4/4) clay loam;
                                                               weak coarse subangular blocky structure; firm; few
                                                               distinct dark reddish brown (5YR 3/3) clay films on
Hickory Series                                                 faces of peds; few fine rounded black (7.5YR
                                                               2.5/1) concretions of iron-manganese in the
Taxonomic classification: Fine-loamy, mixed, active,
                                                               matrix; 5 percent gravel; slightly acid; clear smooth
   mesic Typic Hapludalfs
                                                               boundary.
                    Typical Pedon                          2C—54 to 60 inches; yellowish brown (10YR 5/4) clay
                                                               loam; massive; firm; common distinct brown
Hickory silt loam, 18 to 35 percent slopes; 320 feet
                                                               (7.5YR 4/4) clay films on rocks and along pores;
south and 2,520 feet west of the northeast corner of
                                                               few medium faint yellowish brown (10YR 5/6) iron
sec. 18, T. 15 N., R. 6 E.; in Bureau County, Illinois;
                                                               masses in the matrix; 4 percent gravel;
USGS Neponset topographic quadrangle; lat. 41
                                                               effervescent; moderately alkaline.
degrees 19 minutes 59 seconds N. and long. 89
degrees 50 minutes 50 seconds W., NAD 27:                               Range in Characteristics
A—0 to 4 inches; dark brown (10YR 3/3) silt loam,          Thickness of the loess: Less than 20 inches
    brown (10YR 5/3) dry; moderate fine granular           Depth to the argillic horizon: More than 40 inches
    structure; friable; common fine and medium roots       Depth to carbonates: More than 40 inches
    throughout; 1 percent gravel; slightly acid; clear     Thickness of the solum: Less than 80 inches
    smooth boundary.
                                                           Ap or A horizon:
Bt1—4 to 13 inches; dark yellowish brown (10YR 4/4)
                                                               Hue—7.5YR or 10YR
    silty clay loam; weak fine subangular blocky
                                                               Value—2 to 4
    structure; friable; common fine roots between
                                                               Chroma—2 or 3
    peds; common prominent brown (7.5YR 4/4) clay
                                                               Texture—silt loam or loam
    films on faces of peds; 2 percent gravel; few fine
    rounded black (7.5YR 2.5/1) concretions of iron-       E horizon (if it occurs):
    manganese in the matrix; slightly acid; clear              Value—4 to 6
    smooth boundary.                                           Chroma—2 to 4
2Bt2—13 to 23 inches; dark yellowish brown (10YR               Texture—silt loam or loam
    4/4) clay loam; moderate fine and medium
                                                           Bt horizon:
    subangular blocky structure; friable; common fine
                                                               Hue—7.5YR, 10YR, or 2.5Y
    roots between peds; many distinct brown (7.5YR
                                                               Value—4 to 6
    4/4) clay films on faces of peds; 5 percent gravel;
                                                               Chroma—3 to 6
    few fine rounded black (7.5YR 2.5/1) concretions
                                                               Texture—clay loam, silty clay loam, loam, or
    of iron-manganese in the matrix; neutral; clear
                                                                  gravelly clay loam
    smooth boundary.
2Bt3—23 to 31 inches; dark yellowish brown (10YR           CB or C horizon:
    4/4) clay loam; moderate medium subangular                Hue—7.5YR, 10YR, or 2.5Y
    blocky structure; firm; few very fine and fine roots      Value—5 to 7
    between peds; many distinct brown (7.5YR 4/4)             Chroma—1 to 8
    clay films on faces of peds; 3 percent gravel; few        Texture—loam, clay loam, or sandy loam or the
    fine rounded black (7.5YR 2.5/1) concretions of              gravelly analogs of these textures
Rock Island County, Illinois                                                                                  57




8D2—Hickory silt loam, 10 to 18 percent                   8D3—Hickory clay loam, 10 to 18 percent
  slopes, eroded                                            slopes, severely eroded
                        Setting                                                  Setting
Landform: Ground moraines                                 Landform: Ground moraines
Position on the landform: Backslopes                      Position on the landform: Backslopes
                    Composition                                               Composition
Hickory and similar soils: 90 percent                     Hickory and similar soils: 90 percent
Dissimilar soils: 10 percent                              Dissimilar soils: 10 percent
                Minor Components                                          Minor Components
Similar soils:                                            Similar soils:
• Soils that are calcareous within a depth of 40          • Soils that are calcareous within a depth of 40
inches                                                    inches
• Soils that have a surface layer of clay loam and that   • Soils that have less clay in the surface layer
are more eroded                                           • Soils that have more sand and less clay in the lower
• Soils that contain more sand and less clay in the       part
lower part
                                                          Dissimilar soils:
Dissimilar soils:                                         • Soils that contain more than 20 inches of loess over
• Soils that contain more than 20 inches of loess over    clayey paleosol till
clayey paleosol till                                      • The well drained Marseilles soils on backslopes and
• The well drained Marseilles soils on backslopes and     footslopes
footslopes
                                                           Properties and Qualities of the Hickory Soil
 Properties and Qualities of the Hickory Soil
                                                          Parent material: Loamy till
Parent material: Loamy till                               Drainage class: Well drained
Drainage class: Well drained                              Slowest permeability within a depth of 40 inches:
Slowest permeability within a depth of 40 inches:             Moderate
    Moderate                                              Permeability below a depth of 60 inches: Moderate
Permeability below a depth of 60 inches: Moderate         Depth to restrictive feature: More than 80 inches
Depth to restrictive feature: More than 80 inches         Available water capacity to a depth of 60 inches: About
Available water capacity to a depth of 60 inches: About       9.4 inches
    10.2 inches                                           Content of organic matter in the surface layer: 0.5 to
Content of organic matter in the surface layer: 1 to 2        1.0 percent
    percent                                               Shrink-swell potential: Moderate
Shrink-swell potential: Moderate                          Flooding: None
Flooding: None                                            Accelerated erosion: The surface layer is mostly
Accelerated erosion: The surface layer has been               subsoil material.
    thinned by erosion.                                   Potential for frost action: Moderate
Potential for frost action: Moderate                      Hazard of corrosion: Moderate for steel and moderate
Hazard of corrosion: Moderate for steel and moderate          for concrete
    for concrete                                          Surface runoff class: Medium
Surface runoff class: Medium                              Susceptibility to water erosion: High
Susceptibility to water erosion: High                     Susceptibility to wind erosion: Slight
Susceptibility to wind erosion: Slight
                                                                          Interpretive Groups
                Interpretive Groups
                                                          Land capability classification: 4e
Land capability classification: 3e                        Prime farmland status: Not prime farmland
Prime farmland status: Not prime farmland                 Hydric soil status: Not hydric
Hydric soil status: Not hydric
58                                                                                                 Soil Survey of




8F—Hickory silt loam, 18 to 35 percent                    8F3—Hickory clay loam, 18 to 35 percent
  slopes                                                     slopes, severely eroded
                       Setting
                                                                                 Setting
Landform: Ground moraines
                                                          Landform: Ground moraines
Position on the landform: Backslopes
                                                          Position on the landform: Backslopes
                    Composition                                               Composition
Hickory and similar soils: 90 percent                     Hickory and similar soils: 90 percent
Dissimilar soils: 10 percent                              Dissimilar soils: 10 percent

                Minor Components                                          Minor Components
Similar soils:                                            Similar soils:
• Soils that are calcareous within a depth of 40          • Soils that are calcareous within a depth of 40
inches                                                    inches
• Soils that have a surface layer of clay loam and that   • Soils that have less clay in the surface layer
are more eroded                                           • Soils that have more sand and less clay in the lower
• Soils that have more sand and less clay in the lower    part
part
                                                          Dissimilar soils:
Dissimilar soils:                                         • Soils that contain more than 20 inches of loess over
• Soils that contain more than 20 inches of loess over    clayey paleosol till
clayey paleosol till                                      • The well drained Marseilles soils on backslopes
• The well drained Marseilles soils on footslopes
                                                           Properties and Qualities of the Hickory Soil
 Properties and Qualities of the Hickory Soil
                                                          Parent material: Loamy till
Parent material: Till                                     Drainage class: Well drained
Drainage class: Well drained                              Slowest permeability within a depth of 40 inches:
Slowest permeability within a depth of 40 inches:             Moderate
    Moderate                                              Permeability below a depth of 60 inches: Moderate
Permeability below a depth of 60 inches: Moderate         Depth to restrictive feature: More than 80 inches
Depth to restrictive feature: More than 80 inches         Available water capacity to a depth of 60 inches: About
Available water capacity to a depth of 60 inches: About       9.9 inches
    10.5 inches                                           Content of organic matter in the surface layer: 0.5 to
Content of organic matter in the surface layer: 1 to 3        1.0 percent
    percent                                               Shrink-swell potential: Moderate
Shrink-swell potential: Moderate                          Flooding: None
Flooding: None                                            Accelerated erosion: The surface layer is mostly
Accelerated erosion: None or slight                           subsoil material.
Potential for frost action: Moderate                      Potential for frost action: Moderate
Hazard of corrosion: Moderate for steel and moderate      Hazard of corrosion: Moderate for steel and moderate
    for concrete                                              for concrete
Surface runoff class: High                                Surface runoff class: High
Susceptibility to water erosion: High                     Susceptibility to water erosion: High
Susceptibility to wind erosion: Slight                    Susceptibility to wind erosion: Slight

                Interpretive Groups                                       Interpretive Groups
Land capability classification: 6e                        Land capability classification: 6e
Prime farmland status: Not prime farmland                 Prime farmland status: Not prime farmland
Hydric soil status: Not hydric                            Hydric soil status: Not hydric
Rock Island County, Illinois                                                                                        59




898F3—Hickory-Sylvan complex, 18 to 35                    Shrink-swell potential: Moderate
   percent slopes, severely eroded                        Flooding: None
                                                          Accelerated erosion: The surface layer is mostly
                        Setting                               subsoil material.
                                                          Potential for frost action: High
Landform: Ground moraines
                                                          Hazard of corrosion: Moderate for steel and moderate
Position on the landform: Hickory—lower part of
                                                              for concrete
    backslopes; Sylvan—upper part of backslopes
                                                          Surface runoff class: High
                    Composition                           Susceptibility to water erosion: High
                                                          Susceptibility to wind erosion: Very slight
Hickory and similar soils: 50 percent
Sylvan and similar soils: 35 percent                                      Interpretive Groups
Dissimilar soils: 15 percent
                                                          Land capability classification: Hickory—6e; Sylvan—6e
                Minor Components                          Prime farmland status: Not prime farmland
                                                          Hydric soil status: Hickory—not hydric; Sylvan—not
Similar soils:
                                                              hydric
• Soils that have less clay in the surface layer
Dissimilar soils:
• The somewhat poorly drained Atlas soils on              898G—Hickory-Sylvan silt loams, 35 to 60
backslopes                                                   percent slopes
 Properties and Qualities of the Hickory Soil
                                                                                  Setting
Parent material: Till
                                                          Landform: Ground moraines
Drainage class: Well drained
                                                          Position on the landform: Hickory—lower part of
Slowest permeability within a depth of 40 inches:
                                                              backslopes; Sylvan—upper part of backslopes
    Moderate
Permeability below a depth of 60 inches: Moderate                             Composition
Depth to restrictive feature: More than 80 inches
                                                          Hickory and similar soils: 60 percent
Available water capacity to a depth of 60 inches: About
                                                          Sylvan and similar soils: 25 percent
    10.1 inches
                                                          Dissimilar soils: 15 percent
Content of organic matter in the surface layer: 0.5 to
    1.0 percent                                                           Minor Components
Shrink-swell potential: Moderate
                                                          Similar soils:
Flooding: None
                                                          • Soils that have a surface layer of clay loam or silty
Accelerated erosion: The surface layer is mostly
                                                          clay loam and that are more eroded
    subsoil material.
Potential for frost action: Moderate                      Dissimilar soils:
Hazard of corrosion: Moderate for steel and moderate      • The somewhat poorly drained Atlas soils on
    for concrete                                          backslopes
Surface runoff class: High
                                                           Properties and Qualities of the Hickory Soil
Susceptibility to water erosion: High
Susceptibility to wind erosion: Slight                    Parent material: Till
                                                          Drainage class: Well drained
  Properties and Qualities of the Sylvan Soil
                                                          Slowest permeability within a depth of 40 inches:
Parent material: Loess                                        Moderate
Drainage class: Well drained                              Permeability below a depth of 60 inches: Moderate
Slowest permeability within a depth of 40 inches:         Depth to restrictive feature: More than 80 inches
    Moderate                                              Available water capacity to a depth of 60 inches: About
Permeability below a depth of 60 inches: Moderate             10.1 inches
Depth to restrictive feature: More than 80 inches         Content of organic matter in the surface layer: 1 to 2
Available water capacity to a depth of 60 inches: About       percent
    12.1 inches                                           Shrink-swell potential: Moderate
Content of organic matter in the surface layer: 0.5 to    Flooding: None
    1.0 percent                                           Accelerated erosion: None or slight
60                                                                                                 Soil Survey of




Potential for frost action: Moderate                      Dissimilar soils:
Hazard of corrosion: Moderate for steel and moderate      • Soils that contain more than 20 inches of loess over
    for concrete                                          the glacial till
Surface runoff class: High                                • The well drained Marseilles soils on backslopes
Susceptibility to water erosion: High                     • The somewhat poorly drained Orion and Radford
Susceptibility to wind erosion: Slight                    soils on footslopes
  Properties and Qualities of the Sylvan Soil
                                                           Properties and Qualities of the Hickory Soil
Parent material: Loess
                                                          Parent material: Loamy till
Drainage class: Well drained
                                                          Drainage class: Well drained
Slowest permeability within a depth of 40 inches:
                                                          Slowest permeability within a depth of 40 inches:
    Moderate
                                                              Moderate
Permeability below a depth of 60 inches: Moderate
                                                          Permeability below a depth of 60 inches: Moderate
Depth to restrictive feature: More than 80 inches
                                                          Depth to restrictive feature: More than 80 inches
Available water capacity to a depth of 60 inches: About
                                                          Available water capacity to a depth of 60 inches: About
    12.1 inches
                                                              9.9 inches
Content of organic matter in the surface layer: 1 to 2
                                                          Content of organic matter in the surface layer: 0.5 to
    percent
                                                              1.0 percent
Shrink-swell potential: Moderate
                                                          Shrink-swell potential: Moderate
Flooding: None
                                                          Flooding: None
Accelerated erosion: None or slight
                                                          Accelerated erosion: The surface layer is mostly
Potential for frost action: High
                                                              subsoil material.
Hazard of corrosion: Moderate for steel and moderate
                                                          Potential for frost action: Moderate
    for concrete
                                                          Hazard of corrosion: Moderate for steel and moderate
Surface runoff class: High
                                                              for concrete
Susceptibility to water erosion: High
                                                          Surface runoff class: Medium
Susceptibility to wind erosion: Slight
                                                          Susceptibility to water erosion: High
                Interpretive Groups                       Susceptibility to wind erosion: Slight
Land capability classification: Hickory—7e; Sylvan—7e
                                                             Properties and Qualities of the Atlas Soil
Prime farmland status: Not prime farmland
Hydric soil status: Hickory—not hydric; Sylvan—not        Parent material: Paleosol that formed in till
    hydric                                                Drainage class: Somewhat poorly drained
                                                          Slowest permeability within a depth of 40 inches: Very
                                                              slow
946D3—Hickory-Atlas complex, 10 to 18                     Permeability below a depth of 60 inches: Slow
   percent slopes, severely eroded                        Depth to restrictive feature: More than 80 inches
                                                          Available water capacity to a depth of 60 inches: About
                       Setting
                                                              8 inches
Landform: Ground moraines                                 Content of organic matter in the surface layer: 0.5 to
Position on the landform: Hickory—lower and middle            1.0 percent
    parts of backslopes; Atlas—upper and middle           Shrink-swell potential: High
    parts of backslopes                                   Depth and months of the highest perched seasonal
                                                              high water table: 0.5 foot, January to May
                    Composition
                                                          Flooding: None
Hickory and similar soils: 50 percent                     Accelerated erosion: The surface layer is mostly
Atlas and similar soils: 35 percent                           subsoil material.
Dissimilar soils: 15 percent                              Potential for frost action: High
                                                          Hazard of corrosion: High for steel and moderate for
                Minor Components
                                                              concrete
Similar soils:                                            Surface runoff class: Very high
• Soils that are calcareous within a depth of 40 inches   Susceptibility to water erosion: Moderate
• Soils that have less clay in the surface layer          Susceptibility to wind erosion: Very slight
Rock Island County, Illinois                                                                                        61




                Interpretive Groups                          Properties and Qualities of the Atlas Soil
Land capability classification: Hickory—4e; Atlas—6e      Parent material: Paleosol that formed in till
Prime farmland status: Not prime farmland                 Drainage class: Somewhat poorly drained
Hydric soil status: Hickory—not hydric; Atlas—not         Slowest permeability within a depth of 40 inches: Very
    hydric                                                    slow
                                                          Permeability below a depth of 60 inches: Slow
                                                          Depth to restrictive feature: More than 80 inches
946F3—Hickory-Atlas complex, 18 to 35                     Available water capacity to a depth of 60 inches: About
   percent slopes, severely eroded                            8 inches
                                                          Content of organic matter in the surface layer: 0.5 to
                        Setting
                                                              1.0 percent
Landform: Ground moraines                                 Shrink-swell potential: High
Position on the landform: Hickory—lower and middle        Depth and months of the highest perched seasonal
    parts of backslopes; Atlas—upper and middle               high water table: 0.5 foot, January to May
    parts of backslopes                                   Flooding: None
                                                          Accelerated erosion: The surface layer is mostly
                    Composition
                                                              subsoil material.
Hickory and similar soils: 50 percent                     Potential for frost action: High
Atlas and similar soils: 40 percent                       Hazard of corrosion: High for steel and moderate for
Dissimilar soils: 10 percent                                  concrete
                                                          Surface runoff class: Very high
                Minor Components
                                                          Susceptibility to water erosion: High
Similar soils:                                            Susceptibility to wind erosion: Moderate
• Soils that are calcareous within a depth of 40 inches
                                                                          Interpretive Groups
• Soils that have less clay in the surface layer
                                                          Land capability classification: Hickory—6e; Atlas—6e
Dissimilar soils:
                                                          Prime farmland status: Not prime farmland
• Soils that contain deposits of loess over the glacial
                                                          Hydric soil status: Hickory—not hydric; Atlas—not
till
                                                              hydric
• The well drained Marseilles soils on backslopes
• The somewhat poorly drained Orion and Radford
soils on toeslopes
                                                          960D2—Hickory-Sylvan-Fayette silt
 Properties and Qualities of the Hickory Soil                loams, 10 to 18 percent slopes, eroded
Parent material: Till
                                                                                  Setting
Drainage class: Well drained
Slowest permeability within a depth of 40 inches:         Landform: Ground moraines
    Moderate                                              Position on the landform: Hickory—lower part of
Permeability below a depth of 60 inches: Moderate             backslopes; Sylvan—middle part of backslopes;
Depth to restrictive feature: More than 80 inches             Fayette—upper part of backslopes
Available water capacity to a depth of 60 inches: About
                                                                              Composition
    9.9 inches
Content of organic matter in the surface layer: 0.5 to    Hickory and similar soils: 35 percent
    1.0 percent                                           Sylvan and similar soils: 35 percent
Shrink-swell potential: Moderate                          Fayette and similar soils: 30 percent
Flooding: None
                                                                          Minor Components
Accelerated erosion: The surface layer is mostly
    subsoil material.                                     Similar soils:
Potential for frost action: Moderate                      • Soils that have a surface layer of clay loam or silty
Hazard of corrosion: Moderate for steel and moderate      clay loam and that are more eroded
    for concrete
                                                           Properties and Qualities of the Hickory Soil
Surface runoff class: High
Susceptibility to water erosion: High                     Parent material: Till
Susceptibility to wind erosion: Moderate                  Drainage class: Well drained
62                                                                                                   Soil Survey of




Slowest permeability within a depth of 40 inches:         Accelerated erosion: The surface layer has been
    Moderate                                                  thinned by erosion.
Permeability below a depth of 60 inches: Moderate         Potential for frost action: High
Depth to restrictive feature: More than 80 inches         Hazard of corrosion: Moderate for steel and moderate
Available water capacity to a depth of 60 inches: About       for concrete
    10.2 inches                                           Surface runoff class: Medium
Content of organic matter in the surface layer: 1 to 2    Susceptibility to water erosion: High
    percent                                               Susceptibility to wind erosion: Slight
Shrink-swell potential: Moderate
Flooding: None                                                            Interpretive Groups
Accelerated erosion: The surface layer has been
                                                          Land capability classification: Hickory—3e; Sylvan—
    thinned by erosion.
                                                              3e; Fayette—3e
Potential for frost action: Moderate
                                                          Prime farmland status: Not prime farmland
Hazard of corrosion: Moderate for steel and moderate
                                                          Hydric soil status: Hickory—not hydric; Sylvan—not
    for concrete
                                                              hydric; Fayette—not hydric
Surface runoff class: Medium
Susceptibility to water erosion: High
Susceptibility to wind erosion: Slight
                                                          960D3—Hickory-Sylvan-Fayette complex,
  Properties and Qualities of the Sylvan Soil                10 to 18 percent slopes, severely
Parent material: Loess                                       eroded
Drainage class: Well drained                                                      Setting
Slowest permeability within a depth of 40 inches:
                                                          Landform: Ground moraines
    Moderate
                                                          Position on the landform: Backslopes
Permeability below a depth of 60 inches: Moderate
Depth to restrictive feature: More than 80 inches                             Composition
Available water capacity to a depth of 60 inches: About
                                                          Hickory and similar soils: 35 percent
    12 inches
                                                          Sylvan and similar soils: 35 percent
Content of organic matter in the surface layer: 1 to 2
                                                          Fayette and similar soils: 30 percent
    percent
Shrink-swell potential: Moderate                                          Minor Components
Flooding: None
                                                          Similar soils:
Accelerated erosion: The surface layer has been
                                                          • Soils that have less clay in the surface layer
    thinned by erosion.
Potential for frost action: High
                                                           Properties and Qualities of the Hickory Soil
Hazard of corrosion: Moderate for steel and moderate
    for concrete                                          Parent material: Till
Surface runoff class: Medium                              Drainage class: Well drained
Susceptibility to water erosion: High                     Slowest permeability within a depth of 40 inches:
Susceptibility to wind erosion: Slight                        Moderate
                                                          Permeability below a depth of 60 inches: Moderate
 Properties and Qualities of the Fayette Soil
                                                          Depth to restrictive feature: More than 80 inches
Parent material: Loess                                    Available water capacity to a depth of 60 inches: About
Drainage class: Well drained                                  9.4 inches
Slowest permeability within a depth of 40 inches:         Content of organic matter in the surface layer: 0.5 to
    Moderate                                                  1.0 percent
Permeability below a depth of 60 inches: Moderate         Shrink-swell potential: Moderate
Depth to restrictive feature: More than 80 inches         Flooding: None
Available water capacity to a depth of 60 inches: About   Accelerated erosion: The surface layer is mostly
    11.4 inches                                               subsoil material.
Content of organic matter in the surface layer: 1 to 2    Potential for frost action: Moderate
    percent                                               Hazard of corrosion: Moderate for steel and moderate
Shrink-swell potential: Moderate                              for concrete
Flooding: None                                            Surface runoff class: Medium
Rock Island County, Illinois                                                                                        63




Susceptibility to water erosion: High                     960F—Hickory-Sylvan-Fayette silt loams,
Susceptibility to wind erosion: Moderate                     18 to 30 percent slopes
  Properties and Qualities of the Sylvan Soil
                                                                                  Setting
Parent material: Loess
                                                          Landform: Ground moraines
Drainage class: Well drained
                                                          Position on the landform: Hickory—lower part of
Slowest permeability within a depth of 40 inches:
                                                              backslopes; Sylvan—middle part of backslopes;
    Moderate
                                                              Fayette—upper part of backslopes
Permeability below a depth of 60 inches: Moderate
Depth to restrictive feature: More than 80 inches                             Composition
Available water capacity to a depth of 60 inches: About
                                                          Hickory and similar soils: 40 percent
    12.2 inches
                                                          Sylvan and similar soils: 40 percent
Content of organic matter in the surface layer: 0.5 to
                                                          Fayette and similar soils: 20 percent
    1.0 percent
Shrink-swell potential: Moderate                                          Minor Components
Flooding: None
                                                          Similar soils:
Accelerated erosion: The surface layer is mostly
                                                          • Soils that have a surface layer of clay loam or silty
    subsoil material.
                                                          clay loam and that are more eroded
Potential for frost action: High
Hazard of corrosion: Moderate for steel and moderate
                                                           Properties and Qualities of the Hickory Soil
    for concrete
Surface runoff class: Medium                              Parent material: Till
Susceptibility to water erosion: High                     Drainage class: Well drained
Susceptibility to wind erosion: Very slight               Slowest permeability within a depth of 40 inches:
                                                              Moderate
 Properties and Qualities of the Fayette Soil
                                                          Permeability below a depth of 60 inches: Moderate
Parent material: Loess                                    Depth to restrictive feature: More than 80 inches
Drainage class: Well drained                              Available water capacity to a depth of 60 inches: About
Slowest permeability within a depth of 40 inches:             10.4 inches
    Moderate                                              Content of organic matter in the surface layer: 1 to 2
Permeability below a depth of 60 inches: Moderate             percent
Depth to restrictive feature: More than 80 inches         Shrink-swell potential: Moderate
Available water capacity to a depth of 60 inches: About   Flooding: None
    11.4 inches                                           Accelerated erosion: None or slight
Content of organic matter in the surface layer: 0.5 to    Potential for frost action: Moderate
    1.0 percent                                           Hazard of corrosion: Moderate for steel and moderate
Shrink-swell potential: Moderate                              for concrete
Flooding: None                                            Surface runoff class: High
Accelerated erosion: The surface layer is mostly          Susceptibility to water erosion: High
    subsoil material.                                     Susceptibility to wind erosion: Slight
Potential for frost action: High
                                                            Properties and Qualities of the Sylvan Soil
Hazard of corrosion: Moderate for steel and moderate
    for concrete                                          Parent material: Loess
Surface runoff class: Medium                              Drainage class: Well drained
Susceptibility to water erosion: High                     Slowest permeability within a depth of 40 inches:
Susceptibility to wind erosion: Very slight                   Moderate
                                                          Permeability below a depth of 60 inches: Moderate
                Interpretive Groups
                                                          Depth to restrictive feature: More than 80 inches
Land capability classification: Hickory—4e; Sylvan—       Available water capacity to a depth of 60 inches: About
    4e; Fayette—4e                                            12.2 inches
Prime farmland status: Not prime farmland                 Content of organic matter in the surface layer: 1 to 2
Hydric soil status: Hickory—not hydric; Sylvan—not            percent
    hydric; Fayette—not hydric                            Shrink-swell potential: Moderate
64                                                                                                 Soil Survey of




Flooding: None                                               friable; common very fine roots throughout;
Accelerated erosion: None or slight                          neutral; clear smooth boundary.
Potential for frost action: High                          A—10 to 14 inches; very dark grayish brown (10YR
Hazard of corrosion: Moderate for steel and moderate         3/2) sandy loam, grayish brown (10YR 5/2) dry;
    for concrete                                             weak medium and fine subangular blocky
Surface runoff class: High                                   structure; very friable; common very fine roots
Susceptibility to water erosion: High                        throughout; common faint very dark brown (10YR
Susceptibility to wind erosion: Slight                       2/2) organic coatings on faces of peds; neutral;
                                                             clear smooth boundary.
 Properties and Qualities of the Fayette Soil
                                                          Bw1—14 to 21 inches; brown (10YR 5/3) sandy loam;
Parent material: Loess                                       weak medium subangular blocky structure; very
Drainage class: Well drained                                 friable; few very fine roots between peds; few
Slowest permeability within a depth of 40 inches:            distinct very dark grayish brown (10YR 3/2)
    Moderate                                                 organic coatings on faces of peds and in root
Permeability below a depth of 60 inches: Moderate            channels; common fine faint dark grayish brown
Depth to restrictive feature: More than 80 inches            (10YR 4/2) iron depletions and common fine
Available water capacity to a depth of 60 inches: About      distinct yellowish brown (10YR 5/6) iron masses in
    11.6 inches                                              the matrix; neutral; clear smooth boundary.
Content of organic matter in the surface layer: 2 to 3    Bw2—21 to 38 inches; brown (10YR 5/3) sandy loam;
    percent                                                  weak coarse subangular blocky structure; very
Shrink-swell potential: Moderate                             friable; few very fine roots between peds; common
Flooding: None                                               fine faint grayish brown (10YR 5/2) iron depletions
Accelerated erosion: None or slight                          and common fine distinct yellowish brown (10YR
Potential for frost action: High                             5/8) iron masses in the matrix; slightly acid; abrupt
Hazard of corrosion: Moderate for steel and moderate         smooth boundary.
    for concrete                                          C—38 to 60 inches; pale brown (10YR 6/3) sand;
Surface runoff class: High                                   single grain; loose; common fine faint light
Susceptibility to water erosion: High                        brownish gray (10YR 6/2) iron depletions and
Susceptibility to wind erosion: Slight                       common fine prominent yellowish brown (10YR
                                                             5/8) iron masses in the matrix; neutral.
               Interpretive Groups
Land capability classification: Hickory—6e; Sylvan—                   Range in Characteristics
    6e; Fayette—6e
                                                          Thickness of the mollic epipedon: 10 to 24 inches
Prime farmland status: Not prime farmland
                                                          Depth to free carbonates: More than 40 inches
Hydric soil status: Hickory—not hydric; Sylvan—not
                                                          Thickness of the solum: 20 to 54 inches
    hydric; Fayette—not hydric
                                                          Ap or A horizon:
                                                              Hue—7.5YR or 10YR
Hoopeston Series                                              Value—2 or 3
                                                              Chroma—1 to 3
Taxonomic classification: Coarse-loamy, mixed,
                                                              Texture—sandy loam, fine sandy loam, or loam
   superactive, mesic Aquic Hapludolls
                                                          Bw, Bt, Bg, and/or Btg horizon:
                   Typical Pedon
                                                              Hue—7.5YR, 10YR, or 2.5Y
Hoopeston sandy loam, 0 to 2 percent slopes; 2,530            Value—4 to 6
feet south and 1,060 feet east of the northwest corner        Chroma—1 to 6
of sec. 14, T. 19 N., R. 4 E.; in Whiteside County,           Texture—sandy loam or fine sandy loam; strata of
Illinois; USGS Erie topographic quadrangle; lat. 41              loamy sand, loamy fine sand, loam, sandy clay
degrees 38 minutes 04 seconds N. and long. 90                    loam, silt loam, or sand in some pedons
degrees 00 minutes 45 seconds W., NAD 27:
                                                          Cg and/or C horizon:
Ap—0 to 10 inches; black (10YR 2/1) sandy loam,              Hue—7.5YR to 5Y
   dark gray (10YR 4/1) dry; weak fine subangular            Value—3 to 6
   blocky structure parting to weak fine granular; very      Chroma—1 to 8
Rock Island County, Illinois                                                                                     65




    Texture—loamy sand, sand, loamy fine sand, or         Joslin Series
      fine sand; loamy strata in some pedons
                                                          Taxonomic classification: Fine-loamy, mixed,
                                                             superactive, mesic Typic Argiudolls
172A—Hoopeston sandy loam, 0 to 2
   percent slopes                                                             Typical Pedon
                                                          Joslin silt loam, 2 to 5 percent slopes; 1,980 feet north
                        Setting
                                                          and 578 feet east of the southwest corner of the
Landform: Outwash plains                                  southeast quarter of sec. 8, T. 18 N., R. 1 E.; in
Position on the landform: Summits                         Whiteside County, Illinois; USGS Silvis topographic
                                                          quadrangle; lat. 41 degrees 33 minutes 54 seconds N.
                    Composition
                                                          and long. 90 degrees 24 minutes 09 seconds W., NAD
Hoopeston and similar soils: 92 percent                   27:
Dissimilar soils: 8 percent
                                                          Ap—0 to 9 inches; black (10YR 2/1) silt loam, dark
                Minor Components                              gray (10YR 4/1) dry; moderate fine and medium
                                                              granular structure; friable; few sand grains; slightly
Similar soils:
                                                              alkaline; abrupt smooth boundary.
• Soils that have more clay and less sand
                                                          A—9 to 15 inches; very dark gray (10YR 3/1) silt loam,
• Soils that have less clay and more sand
                                                              gray (10YR 5/1) dry; moderate fine and medium
• Soils that have a seasonal high water table within a
                                                              granular structure; friable; few sand grains; neutral;
depth of 1 foot
                                                              clear smooth boundary.
Dissimilar soils:                                         BA—15 to 20 inches; mixed brown (10YR 4/3) and
• The well drained Dickinson soils and other well             very dark gray (10YR 3/1) silt loam; moderate fine
drained soils; on summits                                     and medium subangular blocky structure; friable;
• Poorly drained soils on toeslopes                           few black (10YR 2/1) organic stains along root
                                                              channels; light gray (10YR 7/1) (dry) silt coatings
         Properties and Qualities of the
                                                              on faces of peds; few sand grains; slightly acid;
                Hoopeston Soil
                                                              clear smooth boundary.
Parent material: Outwash                                  Bt1—20 to 28 inches; brown (10YR 4/3) silt loam;
Drainage class: Somewhat poorly drained                       moderate medium and coarse subangular blocky
Slowest permeability within a depth of 40 inches:             structure; friable; common faint dark brown
    Moderately rapid                                          (10YR 3/3) clay films on faces of peds; common
Permeability below a depth of 60 inches: Rapid                very dark gray (10YR 3/1) organic stains along
Depth to restrictive feature: More than 80 inches             root channels; few wormcasts; 20 percent sand;
Available water capacity to a depth of 60 inches: About       few pebbles; slightly acid; gradual smooth
    7.3 inches                                                boundary.
Content of organic matter in the surface layer: 2 to 3    Bt2—28 to 37 inches; yellowish brown (10YR 5/4) silt
    percent                                                   loam; weak medium prismatic structure parting to
Shrink-swell potential: Low                                   moderate medium subangular blocky; friable;
Depth and months of the highest apparent seasonal             common prominent brown (7.5YR 4/2) clay films
    high water table: 1 foot, January to June                 on faces of peds; few black (10YR 2/1) organic
Flooding: None                                                stains along root channels; 12 percent sand;
Accelerated erosion: None or slight                           moderately acid; gradual smooth boundary.
Potential for frost action: High                          Bt3—37 to 43 inches; yellowish brown (10YR 5/4) silt
Hazard of corrosion: Low for steel and moderate for           loam; weak coarse prismatic structure; friable;
    concrete                                                  common prominent brown (7.5YR 4/2) clay films
Surface runoff class: Very low                                on faces of peds; few black (10YR 2/1) organic
Susceptibility to water erosion: Slight                       stains along root channels; few strata of reddish
Susceptibility to wind erosion: Moderately high               brown (5YR 4/4) silty clay; 3 percent sand; slightly
                                                              acid; clear smooth boundary.
                Interpretive Groups
                                                          2Bt4—43 to 50 inches; reddish brown (5YR 4/4) silty
Land capability classification: 2s                            clay; moderate medium and coarse prismatic
Prime farmland status: Prime farmland                         structure; very firm; few distinct weak red (2.5YR
Hydric soil status: Not hydric                                4/2) clay films on faces of peds; few root channels
66                                                                                                Soil Survey of




    filled with brownish yellow (10YR 6/6) material;     • Soils that have less silt and clay and more sand in
    neutral; abrupt smooth boundary.                     the upper part
2Bt5—50 to 53 inches; reddish brown (5YR 4/4) silty      • Soils that have a perched seasonal high water table
    clay; moderate medium and coarse angular blocky      within a depth of 60 inches
    structure; very firm; few distinct weak red (2.5YR
                                                           Properties and Qualities of the Joslin Soil
    4/2) clay films on faces of peds; many medium
    prominent weak red (2.5YR 5/2) mottles; neutral;     Parent material: Lacustrine deposits
    abrupt smooth boundary.                              Drainage class: Well drained
3C—53 to 85 inches; variegated grayish brown (10YR       Slowest permeability within a depth of 40 inches:
    5/2), yellowish brown (10YR 5/6), and strong             Moderate
    brown (7.5YR 5/6) silt loam; massive; friable; few   Permeability below a depth of 60 inches: Very slow
    strata of reddish brown (5YR 4/4) silty clay; few    Depth to restrictive feature: 40 to 60 inches to bedrock
    prominent concretions of iron and manganese              (lithic)
    oxides throughout the matrix; slightly alkaline.     Available water capacity to a depth of 60 inches: About
                                                             9.6 inches
             Range in Characteristics
                                                         Content of organic matter in the surface layer: 2 to 3
Thickness of the solum: 48 to 72 inches                      percent
                                                         Shrink-swell potential: Moderate
Ap or A horizon:
                                                         Flooding: None
    Hue—10YR
                                                         Accelerated erosion: None or slight
    Value—2 or 3
                                                         Potential for frost action: Moderate
    Chroma—1 to 3
                                                         Hazard of corrosion: Moderate for steel and moderate
    Texture—silt loam or loam
                                                             for concrete
Bw or Bt horizon:                                        Surface runoff class: Low
   Hue—7.5YR or 10YR                                     Susceptibility to water erosion: Slight
   Value—4 or 5                                          Susceptibility to wind erosion: Moderately high
   Chroma—3 to 5
   Texture—silt loam or loam                                             Interpretive Groups
2Bt or 2BC horizon:                                      Land capability classification: 1
    Hue—2.5YR                                            Prime farmland status: Prime farmland
    Value—4 to 6                                         Hydric soil status: Not hydric
    Chroma—4 to 6
    Texture—silty clay loam, silty clay, or clay
3C horizon:                                              763A—Joslin silt loam, 0 to 2 percent
    Texture—silt loam, silty clay loam, loam, or clay       slopes
      loam; stratified in some pedons                                            Setting
                                                         Landform: Lake plains
525A—Joslin loam, bedrock substratum,                                        Composition
   0 to 2 percent slopes
                                                         Joslin and similar soils: 97 percent
                        Setting                          Dissimilar soils: 3 percent
Landform: Lake plains
                                                                         Minor Components
                    Composition
                                                         Similar soils:
Joslin and similar soils: 100 percent                    • Soils that have a thinner or lighter colored surface
                                                         layer
                Minor Components
                                                         • Soils that have less sand and more clay in the
Similar soils:                                           underlying material
• Soils that have bedrock at a depth of less than 40     • Soils that have less silt and clay and more sand in
inches or more than 60 inches                            the upper part
• Soils that have more clay and less sand in the         • Soils that have a perched seasonal high water table
underlying material                                      within a depth of 60 inches
Rock Island County, Illinois                                                                                      67




Dissimilar soils:                                           Properties and Qualities of the Joslin Soil
• Somewhat poorly drained soils on summits
                                                          Parent material: Lacustrine deposits
  Properties and Qualities of the Joslin Soil             Drainage class: Well drained
                                                          Slowest permeability within a depth of 40 inches:
Parent material: Lacustrine deposits
                                                              Moderate
Drainage class: Well drained
                                                          Permeability below a depth of 60 inches: Moderately
Slowest permeability within a depth of 40 inches:
                                                              slow
    Moderate
                                                          Depth to restrictive feature: More than 80 inches
Permeability below a depth of 60 inches: Moderately
                                                          Available water capacity to a depth of 60 inches: About
    slow
                                                              11.5 inches
Depth to restrictive feature: More than 80 inches
                                                          Content of organic matter in the surface layer: 4 to 5
Available water capacity to a depth of 60 inches: About
                                                              percent
    11.5 inches
                                                          Shrink-swell potential: Moderate
Content of organic matter in the surface layer: 4 to 5
                                                          Flooding: None
    percent
                                                          Accelerated erosion: None or slight
Shrink-swell potential: Moderate
                                                          Potential for frost action: Moderate
Flooding: None
                                                          Hazard of corrosion: High for steel and moderate for
Accelerated erosion: None or slight
                                                              concrete
Potential for frost action: Moderate
                                                          Surface runoff class: Low
Hazard of corrosion: High for steel and moderate for
                                                          Susceptibility to water erosion: Slight
    concrete
                                                          Susceptibility to wind erosion: Slight
Surface runoff class: Low
Susceptibility to water erosion: Slight                                   Interpretive Groups
Susceptibility to wind erosion: Slight
                                                          Land capability classification: 2e
                Interpretive Groups                       Prime farmland status: Prime farmland
                                                          Hydric soil status: Not hydric
Land capability classification: 1
Prime farmland status: Prime farmland
Hydric soil status: Not hydric                            Joy Series
                                                          Taxonomic classification: Fine-silty, mixed,
763B—Joslin silt loam, 2 to 5 percent                        superactive, mesic Aquic Hapludolls
   slopes                                                                    Typical Pedon
                        Setting
                                                          Joy silt loam, 0 to 2 percent slopes; 1,900 feet east
Landform: Lake plains                                     and 2,600 feet north of the southwest corner of sec.
                                                          26, T. 18 N., R. 3 E.; in Whiteside County, Illinois;
                    Composition
                                                          USGS Spring Hill topographic quadrangle; lat. 41
Joslin and similar soils: 97 percent                      degrees 31 minutes 01 second N. and long. 90
Dissimilar soils: 3 percent                               degrees 06 minutes 59 seconds W., NAD 27:
                Minor Components                          Ap—0 to 5 inches; black (10YR 2/1) silt loam, dark
                                                             grayish brown (10YR 4/2) dry; moderate medium
Similar soils:
                                                             granular structure; friable; moderately acid; abrupt
• Soils that have a thinner or lighter colored surface
                                                             smooth boundary.
layer
                                                          A1—5 to 13 inches; very dark gray (10YR 3/1) silt
• Soils that have less sand and more clay in the
                                                             loam, dark grayish brown (10YR 4/2) dry; weak
underlying material
                                                             fine subangular blocky structure parting to
• Soils that have less silt and clay and more sand in
                                                             moderate medium granular; friable; slightly acid;
the upper part
                                                             clear smooth boundary.
• Soils that have a perched seasonal high water table
                                                          A2—13 to 17 inches; very dark grayish brown (10YR
within a depth of 60 inches
                                                             3/2) silt loam; moderate fine subangular blocky
Dissimilar soils:                                            structure parting to moderate medium granular;
• Somewhat poorly drained soils on summits                   friable; neutral; clear smooth boundary.
68                                                                                                 Soil Survey of




Bt1—17 to 21 inches; brown (10YR 4/3) silt loam;          C or Cg horizon:
   moderate medium and fine subangular blocky                 Hue—10YR, 2.5Y, or 5Y
   structure; friable; common faint dark grayish brown        Value—4 to 7
   (10YR 4/2) clay films on faces of peds; neutral;           Chroma—1 to 4
   clear smooth boundary.                                     Texture—silt loam, very fine sandy loam, or loam
Bt2—21 to 27 inches; mixed grayish brown (10YR 5/2)
   and brown (10YR 5/3) silty clay loam; moderate
   medium and fine subangular blocky structure;           275A—Joy silt loam, 0 to 2 percent slopes
   friable; common faint dark grayish brown (10YR
                                                                                 Setting
   4/2) clay films on faces of peds; few prominent
   black (7.5YR 2.5/1) coatings of iron-manganese         Landform: Ground moraines
   on faces of peds; common medium distinct               Position on the landform: Summits
   yellowish brown (10YR 5/6) iron masses in the
                                                                              Composition
   matrix; neutral; clear smooth boundary.
Bt3—27 to 34 inches; yellowish brown (10YR 5/4) silt      Joy and similar soils: 95 percent
   loam; moderate fine and medium subangular              Dissimilar soils: 5 percent
   blocky structure; friable; common faint brown
                                                                          Minor Components
   (10YR 5/3) clay films on faces of peds; few
   prominent black (7.5YR 2.5/1) coatings of iron-        Similar soils:
   manganese on faces of peds; common fine                • Soils that have less silt and more sand throughout
   distinct light brownish gray (10YR 6/2) iron
                                                          Dissimilar soils:
   depletions and yellowish brown (10YR 5/6) iron
                                                          • The well drained Biggsville soils on summits
   masses in the matrix; neutral; clear smooth
                                                          • The excessively drained Oakville soils on
   boundary.
                                                          shoulders
Bt4—34 to 49 inches; mixed light brownish gray (2.5Y
                                                          • The well drained Port Byron soils on shoulders
   6/2) and yellowish brown (10YR 5/6) silt loam;
                                                          • The poorly drained Sable soils in depressions
   weak fine prismatic structure parting to weak fine
   and medium subangular blocky; friable; few faint           Properties and Qualities of the Joy Soil
   grayish brown (10YR 5/2) clay films on faces of
                                                          Parent material: Loess
   peds; few prominent black (7.5YR 2.5/1) coatings
                                                          Drainage class: Somewhat poorly drained
   of iron-manganese on faces of peds; neutral;
                                                          Slowest permeability within a depth of 40 inches:
   gradual smooth boundary.
                                                              Moderate
Cg—49 to 60 inches; light brownish gray (2.5Y 6/2) silt
                                                          Permeability below a depth of 60 inches: Moderate
   loam; massive; friable; common prominent black
                                                          Depth to restrictive feature: More than 80 inches
   (7.5YR 2.5/1) coatings of iron-manganese along
                                                          Available water capacity to a depth of 60 inches: About
   cleavage planes; many medium prominent
                                                              12.9 inches
   yellowish brown (10YR 5/6) iron masses in the
                                                          Content of organic matter in the surface layer: 2 to 4
   matrix; neutral.
                                                              percent
                                                          Shrink-swell potential: Low
            Range in Characteristics
                                                          Depth and months of the highest apparent seasonal
Thickness of the mollic epipedon: 10 to 24 inches             high water table: 1 foot, March to June
Depth to free carbonates: More than 40 inches             Flooding: None
Thickness of the solum: 36 to 60 inches                   Accelerated erosion: None or slight
                                                          Potential for frost action: High
Ap or A horizon:
                                                          Hazard of corrosion: High for steel and moderate for
    Hue—10YR
                                                              concrete
    Value—2 or 3
                                                          Surface runoff class: Low
    Chroma—1 to 3
                                                          Susceptibility to water erosion: Slight
    Texture—silt loam
                                                          Susceptibility to wind erosion: Slight
Bw, Bg, or Bt horizon:
                                                                          Interpretive Groups
    Hue—7.5YR, 10YR, or 2.5Y
    Value—4 to 6                                          Land capability classification: 1
    Chroma—2 to 6                                         Prime farmland status: Prime farmland
    Texture—silt loam or silty clay loam                  Hydric soil status: Not hydric
Rock Island County, Illinois                                                                                    69




Landes Series                                                          Range in Characteristics
                                                           Depth to carbonates (if they occur): More than 40
Taxonomic classification: Coarse-loamy, mixed,
                                                              inches
   superactive, mesic Fluventic Hapludolls
                                                           Depth to the base of the cambic horizon: 22 to 40
                   Typical Pedon                              inches
Landes fine sandy loam, 0 to 2 percent slopes, rarely      Ap, A, and/or AB horizon:
flooded; 99 feet south and 990 feet west of the                Hue—10YR
northeast corner of sec. 4, T. 18 N., R. 11 W.; in             Value—2 or 3
Bureau County, Illinois; USGS Clearlake topographic            Chroma—1 to 3
quadrangle; lat. 40 degrees 02 minutes 51 seconds N.           Texture—fine sandy loam, very fine sandy loam,
and long. 90 degrees 19 minutes 58 seconds W., NAD                sandy loam, loam, loamy fine sand, loamy very
27:                                                               fine sand, loamy sand, or silt loam
                                                               Content of rock fragments—0 to 20 percent
Ap—0 to 5 inches; very dark grayish brown (10YR 3/2)
   fine sandy loam, brown (10YR 4/3) dry; weak fine        Bw horizon:
   subangular blocky structure parting to weak fine           Hue—10YR
   granular; friable; few very fine roots; few fine very      Value—3 to 6
   dark gray (10YR 3/1) organic coatings on faces of          Chroma—2 to 4
   peds; neutral; abrupt smooth boundary.                     Texture—loam, fine sandy loam, very fine sandy
A—5 to 14 inches; very dark grayish brown (10YR 3/2)             loam, sandy loam, loamy fine sand, or loamy
   fine sandy loam, brown (10YR 5/3) dry; weak                   very fine sand
   medium subangular blocky structure; friable; few           Content of rock fragments—0 to 10 percent
   very fine roots; neutral; clear smooth boundary.
                                                           BC and C horizons:
AB—14 to 19 inches; dark brown (10YR 3/3) loam,
                                                              Hue—2.5YR to 10YR
   brown (10YR 5/3) dry; weak fine and medium
                                                              Value—4 to 6
   subangular blocky structure; friable; few very fine
                                                              Chroma—1 to 4
   roots; many faint very dark grayish brown (10YR
                                                              Texture—sand, fine sand, very fine sand, loamy
   3/2) organic coatings on faces of peds; neutral;
                                                                sand, loamy fine sand, loamy very fine sand,
   clear smooth boundary.
                                                                sandy loam, fine sandy loam, very fine sandy
Bw1—19 to 23 inches; brown (10YR 4/3) loam; weak
                                                                loam, loam, or silt loam; stratified in some pedons
   fine and medium subangular blocky structure;
                                                              Content of rock fragments—0 to 10 percent
   friable; few very fine roots; many faint dark brown
   (10YR 3/3) and few faint very dark grayish brown
   (10YR 3/2) organic coatings on faces of peds;           7304A—Landes fine sandy loam, 0 to 2
   neutral; clear smooth boundary.                            percent slopes, rarely flooded
Bw2—23 to 28 inches; brown (10YR 4/3) fine sandy
   loam; weak medium subangular blocky structure;                                 Setting
   friable; few very fine roots; common faint dark
                                                           Landform: Natural levees on flood plains
   brown (10YR 3/3) organic coatings on faces of
   peds; neutral; clear smooth boundary.                                       Composition
Bw3—28 to 32 inches; brown (10YR 4/3) and dark
                                                           Landes and similar soils: 94 percent
   yellowish brown (10YR 4/4) fine sandy loam; weak
                                                           Dissimilar soils: 6 percent
   medium subangular blocky structure; very friable;
   few very fine roots; common faint dark brown                            Minor Components
   (10YR 3/3) organic coatings on faces of peds; less
                                                           Similar soils:
   than 2 percent fine gravel; neutral; clear smooth
                                                           • Soils that have a surface layer less than 10 inches
   boundary.
                                                           thick
BC—32 to 36 inches; dark yellowish brown (10YR 4/4)
                                                           • Soils that contain more sand in the upper part
   and brown (10YR 4/3) loamy sand; weak medium
                                                           • Soils that have a seasonal high water table within a
   subangular blocky structure; very friable; few very
                                                           depth of 48 inches
   fine roots; 5 percent fine gravel; neutral; clear
   smooth boundary.                                        Dissimilar soils:
C—36 to 60 inches; yellowish brown (10YR 5/4) sand;        • The somewhat poorly drained Orion and Radford
   single grain; loose; 2 percent fine gravel; neutral.    soils on footslopes
70                                                                                                  Soil Survey of




 Properties and Qualities of the Landes Soil              Bw1—15 to 21 inches; brown (10YR 5/3) silt loam;
                                                             moderate medium subangular blocky structure;
Parent material: Loamy alluvium
                                                             friable; few fine roots between peds; many faint
Drainage class: Well drained
                                                             dark grayish brown (10YR 4/2) clay films on faces
Slowest permeability within a depth of 40 inches:
                                                             of peds; common fine distinct yellowish brown
    Moderately rapid
                                                             (10YR 5/8) iron masses in the matrix; moderately
Permeability below a depth of 60 inches: Rapid
                                                             acid; clear smooth boundary.
Depth to restrictive feature: More than 80 inches
                                                          Bw2—21 to 26 inches; brown (10YR 5/3) silt loam;
Available water capacity to a depth of 60 inches: About
                                                             moderate medium subangular blocky structure;
    7.7 inches
                                                             friable; few fine roots between peds; few faint dark
Content of organic matter in the surface layer: 1 to 2
                                                             grayish brown (10YR 4/2) clay films on faces of
    percent
                                                             peds; common fine faint grayish brown (10YR 5/2)
Shrink-swell potential: Low
                                                             iron depletions; common fine distinct yellowish
Depth and months of the highest apparent seasonal
                                                             brown (10YR 5/8) iron masses in the matrix;
    high water table: 4 feet, February to April
                                                             strongly acid; clear smooth boundary.
Frequency and most likely period of flooding: Rare,
                                                          Bg—26 to 36 inches; grayish brown (10YR 5/2) loam;
    November to June
                                                             moderate medium and coarse subangular blocky
Potential for frost action: Moderate
                                                             structure; friable; few fine roots between peds; few
Hazard of corrosion: Low for steel and low for concrete
                                                             fine rounded black (7.5YR 2.5/1) concretions of
Surface runoff class: Very low
                                                             iron and manganese oxide in the matrix; common
Susceptibility to water erosion: Slight
                                                             fine prominent yellowish brown (10YR 5/8) iron
Susceptibility to wind erosion: Moderately high
                                                             masses in the matrix; moderately acid; abrupt
               Interpretive Groups                           smooth boundary.
                                                          2C—36 to 54 inches; brown (7.5YR 5/4) coarse sand;
Land capability classification: 2s
                                                             single grain; loose; common fine prominent
Prime farmland status: Prime farmland
                                                             yellowish brown (10YR 5/8) iron oxide in the
Hydric soil status: Not hydric
                                                             matrix; about 5 percent gravel; slightly acid; abrupt
                                                             smooth boundary.
Lawler Series                                             2Cg—54 to 60 inches; dark grayish brown (2.5YR 4/2)
                                                             coarse sand; single grain; loose; about 5 percent
Taxonomic classification: Fine-loamy over sandy or           gravel; slightly acid.
   sandy-skeletal, mixed, superactive, mesic Aquic
                                                                       Range in Characteristics
   Hapludolls
                                                          Thickness of the mollic epipedon: 10 to 24 inches
                   Typical Pedon
                                                          Depth to sandy sediments: 24 to 40 inches
Lawler loam, 0 to 2 percent slopes; 2,180 feet west       Thickness of the solum: 24 to 40 inches
and 160 feet north of the southeast corner of sec. 28,
                                                          Ap or A horizon:
T. 20 N., R. 6 E.; in Whiteside County, Illinois; USGS
                                                              Hue—10YR
Tampico topographic quadrangle; lat. 41 degrees 41
                                                              Value—2 or 3
minutes 09 seconds N. and long. 89 degrees 48
                                                              Chroma—1 or 2
minutes 50 seconds W., NAD 27:
                                                              Texture—loam or silt loam
Ap—0 to 10 inches; black (10YR 2/1) loam, dark
                                                          AB or BA horizon:
   grayish brown (10YR 4/2) dry; weak fine and
                                                             Hue—10YR
   medium granular structure; friable; few very fine
                                                             Value—3
   roots throughout; moderately acid; abrupt smooth
                                                             Chroma—1 or 2
   boundary.
                                                             Texture—loam or clay loam
AB—10 to 15 inches; very dark grayish brown (10YR
   3/2) loam, grayish brown (10YR 5/2) dry; weak          Bw, Bg, and/or BC horizon:
   fine subangular blocky structure parting to weak           Hue—10YR or 2.5Y
   fine granular; friable; few fine roots throughout;         Value—4 to 6
   many faint black (10YR 2/1) organic coatings on            Chroma—2 to 6
   faces of peds; moderately acid; clear smooth               Texture—clay loam, loam, silt loam, or sandy clay
   boundary.                                                    loam
Rock Island County, Illinois                                                                                     71




2C or 2Cg horizon:                                        Lawson Series
   Hue—7.5YR, 10YR, or 2.5Y
   Value—4 to 8                                           Taxonomic classification: Fine-silty, mixed,
   Chroma—1 to 6                                             superactive, mesic Aquic Cumulic Hapludolls
   Texture—loamy coarse sand, loamy sand, coarse
                                                                              Typical Pedon
       sand, or sand or the gravelly or very gravelly
       analogs of these textures                          Lawson silt loam, 0 to 2 percent slopes, occasionally
                                                          flooded; 318 feet south and 1,040 feet east of the
                                                          northwest corner of sec. 17, T. 17 N., R. 9 E.; in
647A—Lawler loam, 0 to 2 percent slopes                   Bureau County, Illinois; USGS Princeton North
                                                          topographic quadrangle; lat. 41 degrees 27 minutes 54
                        Setting
                                                          seconds N. and long. 89 degrees 29 minutes 14
Landform: Outwash plains                                  seconds W., NAD 27:
                    Composition                           Ap—0 to 11 inches; very dark grayish brown (10YR
                                                             3/2) silt loam, dark grayish brown (10YR 4/2) dry;
Lawler and similar soils: 90 percent
                                                             weak medium granular structure; friable; few fine
Dissimilar soils: 10 percent
                                                             roots throughout; neutral; clear smooth boundary.
                Minor Components                          A1—11 to 19 inches; black (10YR 2/1) silt loam, very
                                                             dark gray (10YR 3/1) dry; moderate fine granular
Similar soils:
                                                             structure; friable; few fine roots throughout; neutral;
• Soils that have either more sand or more clay in the
                                                             gradual smooth boundary.
upper part
                                                          A2—19 to 28 inches; very dark grayish brown (10YR
• Soils that have less sand and more silt and clay in
                                                             3/2) silt loam, dark grayish brown (10YR 4/2) dry;
the lower part
                                                             moderate medium granular structure; friable; few
Dissimilar soils:                                            fine roots throughout; neutral; gradual smooth
• The well drained Dickinson soils on summits                boundary.
                                                          C1—28 to 50 inches; dark grayish brown (10YR 4/2)
  Properties and Qualities of the Lawler Soil
                                                             silt loam; weak medium subangular blocky
Parent material: Eolian deposits over outwash                structure; friable; few fine roots throughout;
Drainage class: Somewhat poorly drained                      common faint very dark grayish brown (10YR 3/2)
Slowest permeability within a depth of 40 inches:            organic coatings on faces of peds; very dark
    Moderate                                                 grayish brown (10YR 3/2) krotovina; few fine faint
Permeability below a depth of 60 inches: Very rapid          brown (10YR 4/3) and common fine distinct
Depth to restrictive feature: More than 80 inches            yellowish brown (10YR 5/6) iron masses in the
Available water capacity to a depth of 60 inches: About      matrix; neutral; gradual smooth boundary.
    6.5 inches                                            C2—50 to 60 inches; grayish brown (2.5Y 5/2) silt
Content of organic matter in the surface layer: 4 to 5       loam; weak medium subangular blocky structure;
    percent                                                  friable; few fine roots; very dark grayish brown
Shrink-swell potential: Low                                  (10YR 3/2) krotovina; common fine prominent dark
Depth and months of the highest apparent seasonal            grayish brown (10YR 4/2) iron depletions and
    high water table: 1 foot, January to May                 common fine prominent yellowish brown (10YR
Flooding: None                                               5/6) iron masses in the matrix; neutral.
Accelerated erosion: None or slight
                                                                       Range in Characteristics
Potential for frost action: High
Hazard of corrosion: High for steel and moderate for      Thickness of the mollic epipedon: 24 to 36 inches
    concrete
                                                          Ap or A horizon:
Surface runoff class: Low
                                                              Hue—10YR
Susceptibility to water erosion: Slight
                                                              Value—2 or 3
Susceptibility to wind erosion: Slight
                                                              Chroma—1 or 2
                Interpretive Groups                           Texture—silt loam
Land capability classification: 2s                        C horizon:
Prime farmland status: Prime farmland                        Hue—10YR or 2.5Y
Hydric soil status: Not hydric                               Value—3 to 6
72                                                                                                   Soil Survey of




     Chroma—1 to 3                                        7451A—Lawson silt loam, 0 to 2 percent
     Texture—silt loam                                       slopes, rarely flooded
                                                                                   Setting
3451A—Lawson silt loam, 0 to 2 percent
   slopes, frequently flooded                             Landform: Flood plains
                                                                              Composition
                         Setting
                                                          Lawson and similar soils: 92 percent
Landform: Flood plains
                                                          Dissimilar soils: 8 percent
                    Composition
                                                                          Minor Components
Lawson and similar soils: 91 percent
                                                          Similar soils:
Dissimilar soils: 9 percent
                                                          • Soils that have more sand throughout
                Minor Components                          • Soils that have a buried surface layer within a depth
                                                          of 60 inches
Similar soils:
• Soils that have more sand throughout                    Dissimilar soils:
• Soils that have a buried surface layer within a depth   • The poorly drained Millington and Sawmill soils in
of 60 inches                                              the lower positions on flood plains
Dissimilar soils:
                                                           Properties and Qualities of the Lawson Soil
• The well drained Raddle soils on low terrace
footslopes                                                Parent material: Alluvium
• The poorly drained Sawmill soils in swales              Drainage class: Somewhat poorly drained
                                                          Slowest permeability within a depth of 40 inches:
 Properties and Qualities of the Lawson Soil
                                                              Moderate
Parent material: Alluvium                                 Permeability below a depth of 60 inches: Moderate
Drainage class: Somewhat poorly drained                   Depth to restrictive feature: More than 80 inches
Slowest permeability within a depth of 40 inches:         Available water capacity to a depth of 60 inches: About
    Moderate                                                  12.1 inches
Permeability below a depth of 60 inches: Moderate         Content of organic matter in the surface layer: 3 to 7
Depth to restrictive feature: More than 80 inches             percent
Available water capacity to a depth of 60 inches: About   Shrink-swell potential: Moderate
    12.1 inches                                           Depth and months of the highest apparent seasonal
Content of organic matter in the surface layer: 2 to 4        high water table: 1 foot, January to May
    percent                                               Frequency and most likely period of flooding: Rare,
Shrink-swell potential: Moderate                              November to June
Depth and months of the highest apparent seasonal         Potential for frost action: High
    high water table: 1 foot, January to May              Hazard of corrosion: Moderate for steel and low for
Frequency and most likely period of flooding:                 concrete
    Frequent, November to June                            Surface runoff class: Low
Potential for frost action: High                          Susceptibility to water erosion: Slight
Hazard of corrosion: Moderate for steel and low for       Susceptibility to wind erosion: Slight
    concrete
                                                                          Interpretive Groups
Surface runoff class: Negligible
Susceptibility to water erosion: Slight                   Land capability classification: 2w
Susceptibility to wind erosion: Slight                    Prime farmland status: Prime farmland
                                                          Hydric soil status: Not hydric
                Interpretive Groups
Land capability classification: 3w
Prime farmland status: Prime farmland where               Marseilles Series
    protected from flooding or not frequently flooded
    during the growing season                             Taxonomic classification: Fine-silty, mixed, active,
Hydric soil status: Not hydric                               mesic Typic Hapludalfs
Rock Island County, Illinois                                                                                        73




  Typical Pedon (Official Series Description)               Ap or A horizon:
                                                                Hue—10YR
Marseilles silt loam, 35 to 60 percent slopes, at an
                                                                Value—2 to 5
elevation of 685 feet; 1,400 feet south and 1,150 feet
                                                                Chroma—2 or 3
east of the northwest corner of sec. 14, T. 2 S., R. 6
                                                                Texture—silt loam or silty clay loam
W.; in Bureau County, Illinois; USGS Liberty
topographic quadrangle; lat. 39 degrees 53 minutes 57       E or BE horizon:
seconds N. and long. 91 degrees 03 minutes 53                   Hue—10YR
seconds W., NAD 27:                                             Value—4 or 5
                                                                Chroma—2 to 4
A—0 to 3 inches; very dark grayish brown (10YR 3/2)
                                                                Texture—silt loam
    silt loam, grayish brown (10YR 5/2) dry; moderate
    very fine granular structure; friable; strongly acid;   Bt horizon:
    abrupt smooth boundary.                                     Hue—10YR
E—3 to 7 inches; brown (10YR 5/3) silt loam, very               Value—4 or 5
    pale brown (10YR 7/3) dry; moderate thin platy              Chroma—3 to 6
    and moderate very fine granular structure; friable;         Texture—silt loam or silty clay loam
    very few faint dark grayish brown (10YR 4/2)
                                                            2Bt horizon:
    organic coatings in root channels and/or pores;
                                                                Hue—7.5YR to 2.5Y
    strongly acid; clear smooth boundary.
                                                                Value—4 to 6
BE—7 to 10 inches; yellowish brown (10YR 5/4) silt
                                                                Chroma—2 to 4
    loam; weak medium platy and moderate very fine
                                                                Texture—clay loam, silt loam, silty clay loam, or
    and fine subangular blocky structure; friable; very
                                                                  silty clay
    few faint dark grayish brown (10YR 4/2) organic
    coatings in root channels and/or pores; strongly        2Cr horizon:
    acid; clear smooth boundary.                                Hue—10YR, 2.5Y, 5Y, or N
2Bt1—10 to 17 inches; yellowish brown (10YR 5/4)                Value—4 to 6
    silty clay loam; moderate fine and medium                   Chroma—0 to 4
    subangular blocky structure; firm; very few faint
    dark grayish brown (10YR 4/2) organic coatings in
    root channels and/or pores and few distinct brown       913D2—Marseilles-Hickory silt loams, 10
    (10YR 5/3) clay films on faces of peds; 1 percent          to 18 percent slopes, eroded
    gravel; very strongly acid; clear smooth boundary.
2Bt2—17 to 22 inches; yellowish brown (10YR 5/4)                                    Setting
    silty clay loam; strong medium subangular blocky
                                                            Landform: Ground moraines
    structure; firm; common distinct brown (10YR 5/3)
                                                            Position on the landform: Marseilles—lower part of
    clay films and very few faint very pale brown
                                                                backslopes; Hickory—upper part of
    (10YR 7/3) silt coatings on faces of peds; 1 percent
                                                                backslopes
    gravel; very strongly acid; clear smooth boundary.
2Bt3—22 to 35 inches; light olive brown (2.5Y 5/4) silty                        Composition
    clay loam; moderate medium and coarse
                                                            Marseilles and similar soils: 50 percent
    subangular blocky structure; firm; very few faint
                                                            Hickory and similar soils: 40 percent
    brown (10YR 5/3) clay films and very few distinct
                                                            Dissimilar components: 10 percent
    very pale brown (10YR 7/3) silt coatings on faces
    of peds; 1 percent gravel; very strongly acid;                          Minor Components
    gradual smooth boundary.
                                                            Similar soils:
2Cr—35 to 60 inches; 70 percent light olive brown
                                                            • Soils that have more clay in the subsoil
    (2.5Y 5/4) and 30 percent olive (5Y 5/3) silty clay
                                                            • Soils that formed in calcareous shale
    and unweathered bedrock; massive; firm; 10
    percent shale gravel; very strongly acid.               Dissimilar components:
                                                            • The somewhat poorly drained Atlas soils on
             Range in Characteristics
                                                            backslopes
Depth to the base of the argillic horizon: 20 to 40         • The somewhat poorly drained Orion and Radford
   inches                                                   soils on footslopes
Depth to paralithic contact: 20 to 40 inches                • Areas of rock outcrop on the lower backslopes
74                                                                                                    Soil Survey of




Properties and Qualities of the Marseilles Soil            913F—Marseilles-Hickory silt loams, 18 to
Parent material: Loess over residuum derived from             35 percent slopes
    shale
                                                                                  Setting
Drainage class: Well drained
Slowest permeability within a depth of 40 inches: Very     Landform: Ground moraines
    slow                                                   Position on the landform: Marseilles—lower part of
Permeability below a depth of 60 inches: Very slow             backslopes; Hickory—upper part of backslopes
Depth to restrictive feature: 20 to 40 inches to bedrock
                                                                               Composition
    (paralithic)
Available water capacity to a depth of 60 inches: About    Marseilles and similar soils: 41 percent
    6 inches                                               Hickory and similar soils: 39 percent
Content of organic matter in the surface layer: 1 to 3     Dissimilar soils: 20 percent
    percent
                                                                           Minor Components
Shrink-swell potential: High
Flooding: None                                             Similar soils:
Accelerated erosion: The surface layer has been            • Soils that have more clay in the subsoil
    thinned by erosion.                                    • Soils that formed in calcareous shale
Potential for frost action: High
                                                           Dissimilar soils:
Hazard of corrosion: High for steel and moderate for
                                                           • The somewhat poorly drained Atlas soils on
    concrete
                                                           backslopes
Surface runoff class: Very high
                                                           • The somewhat poorly drained Orion and Radford
Susceptibility to water erosion: High
                                                           soils on footslopes
Susceptibility to wind erosion: Slight
 Properties and Qualities of the Hickory Soil              Properties and Qualities of the Marseilles Soil
Parent material: Till                                      Parent material: Thin layer of loess over residuum
Drainage class: Well drained                                   derived from shale
Slowest permeability within a depth of 40 inches:          Drainage class: Well drained
    Moderate                                               Slowest permeability within a depth of 40 inches: Very
Permeability below a depth of 60 inches: Moderate              slow
Depth to restrictive feature: More than 80 inches          Permeability below a depth of 60 inches: Very slow
Available water capacity to a depth of 60 inches: About    Depth to restrictive feature: 20 to 40 inches to bedrock
    10.2 inches                                                (paralithic)
Content of organic matter in the surface layer: 1 to 2     Available water capacity to a depth of 60 inches: About
    percent                                                    6.3 inches
Shrink-swell potential: Moderate                           Content of organic matter in the surface layer: 1 to 3
Flooding: None                                                 percent
Accelerated erosion: The surface layer has been            Shrink-swell potential: Moderate
    thinned by erosion.                                    Flooding: None
Potential for frost action: Moderate                       Accelerated erosion: None or slight
Hazard of corrosion: Moderate for steel and moderate       Potential for frost action: High
    for concrete                                           Hazard of corrosion: High for steel and moderate for
Surface runoff class: Medium                                   concrete
Susceptibility to water erosion: High                      Surface runoff class: High
Susceptibility to wind erosion: Slight                     Susceptibility to water erosion: High
                                                           Susceptibility to wind erosion: Slight
                Interpretive Groups
                                                            Properties and Qualities of the Hickory Soil
Land capability classification: Marseilles—4e;
    Hickory—3e                                             Parent material: Loamy till
Prime farmland status: Not prime farmland                  Drainage class: Well drained
Hydric soil status: Marseilles—not hydric; Hickory—not     Slowest permeability within a depth of 40 inches:
    hydric                                                     Moderate
Rock Island County, Illinois                                                                                      75




Permeability below a depth of 60 inches: Moderate          Available water capacity to a depth of 60 inches: About
Depth to restrictive feature: More than 80 inches              6 inches
Available water capacity to a depth of 60 inches: About    Content of organic matter in the surface layer: 1 to 3
    10.4 inches                                                percent
Content of organic matter in the surface layer: 1 to 2     Shrink-swell potential: Moderate
    percent                                                Flooding: None
Shrink-swell potential: Moderate                           Accelerated erosion: None or slight
Flooding: None                                             Potential for frost action: High
Accelerated erosion: None or slight                        Hazard of corrosion: High for steel and moderate for
Potential for frost action: Moderate                           concrete
Hazard of corrosion: Moderate for steel and moderate       Surface runoff class: High
    for concrete                                           Susceptibility to water erosion: High
Surface runoff class: High                                 Susceptibility to wind erosion: Slight
Susceptibility to water erosion: High
                                                            Properties and Qualities of the Hickory Soil
Susceptibility to wind erosion: Slight
                                                           Parent material: Till
                Interpretive Groups
                                                           Drainage class: Well drained
Land capability classification: Marseilles—7e;             Slowest permeability within a depth of 40 inches:
    Hickory—6e                                                 Moderate
Prime farmland status: Not prime farmland                  Permeability below a depth of 60 inches: Moderate
Hydric soil status: Marseilles—not hydric; Hickory—not     Depth to restrictive feature: More than 80 inches
    hydric                                                 Available water capacity to a depth of 60 inches: About
                                                               10.5 inches
                                                           Content of organic matter in the surface layer: 1 to 2
913G—Marseilles-Hickory silt loams, 35                         percent
   to 60 percent slopes                                    Shrink-swell potential: Moderate
                                                           Flooding: None
                        Setting
                                                           Accelerated erosion: None or slight
Landform: Ground moraines                                  Potential for frost action: Moderate
Position on the landform: Marseilles—lower part of         Hazard of corrosion: Moderate for steel and moderate
    backslopes; Hickory—upper part of backslopes               for concrete
                                                           Surface runoff class: High
                    Composition
                                                           Susceptibility to water erosion: High
Marseilles and similar soils: 50 percent                   Susceptibility to wind erosion: Slight
Hickory and similar soils: 40 percent
Dissimilar soils: 10 percent                                              Interpretive Groups
                Minor Components                           Land capability classification: Marseilles—7e;
                                                               Hickory—7e
Similar soils:
                                                           Prime farmland status: Not prime farmland
• Soils that have more clay in the subsoil
                                                           Hydric soil status: Marseilles—not hydric; Hickory—not
• Soils that formed in calcareous shale
                                                               hydric
Dissimilar soils:
• The somewhat poorly drained Orion and Radford
soils on footslopes                                        Martinsville Series
Properties and Qualities of the Marseilles Soil
                                                           Taxonomic classification: Fine-loamy, mixed, active,
Parent material: Loess over residuum derived from             mesic Typic Hapludalfs
    shale
                                                             Typical Pedon (Official Series Description)
Drainage class: Well drained
Slowest permeability within a depth of 40 inches: Very     Martinsville silt loam, 2 to 5 percent slopes, at an
    slow                                                   elevation of 705 feet; 200 feet north and 2,440 feet
Permeability below a depth of 60 inches: Very slow         west of the center of sec. 36, T. 21 N., R. 7 E.; in
Depth to restrictive feature: 20 to 40 inches to bedrock   Champaign County, Illinois; USGS Rising topographic
    (paralithic)                                           quadrangle; lat. 40 degrees 13 minutes 53 seconds N.
76                                                                                                        Soil Survey of




and long. 88 degrees 21 minutes 52 seconds W., NAD           Bt, 2Bt, BC, and/or 2BC horizon:
27:                                                               Hue—7.5YR or 10YR
                                                                  Value—3 to 6
Ap—0 to 6 inches; mixed dark grayish brown (10YR
                                                                  Chroma—3 to 6
    4/2) and yellowish brown (10YR 5/4) silt loam,
                                                                  Texture—clay loam, loam, sandy clay loam, silty
    pale brown (10YR 6/3) dry; moderate fine and
                                                                    clay loam, or silt loam in the upper part; clay
    medium granular structure; friable; slightly acid;
                                                                    loam, loam, sandy clay loam, silty clay loam, silt
    abrupt smooth boundary.
                                                                    loam, sandy loam, fine sandy loam, or very fine
E—6 to 9 inches; brown (10YR 4/3) silt loam, light
                                                                    sandy loam in the lower part; stratified in some
    yellowish brown (10YR 6/4) dry; weak medium
                                                                    pedons
    platy structure parting to moderate medium
    subangular blocky; friable; light gray (10YR 7/1) silt   C or 2C horizon:
    coatings on faces of peds; few thin dark grayish             Hue—10YR
    brown (10YR 4/2) films on faces of peds; neutral;            Value—3 to 6
    abrupt smooth boundary.                                      Chroma—3 to 6
Bt1—9 to 18 inches; yellowish brown (10YR 5/4) silty             Texture—stratified; dominantly fine sandy loam,
    clay loam; moderate fine and medium subangular                 sandy loam, loam, or silt loam
    blocky structure; friable; many thin brown (10YR
    4/3) clay films on faces of peds; common fine
    accumulations of iron and manganese; slightly            570B—Martinsville silt loam, 2 to 5
    acid; clear smooth boundary.                                percent slopes
2Bt2—18 to 33 inches; dark yellowish brown (10YR
                                                                                     Setting
    4/4) clay loam; moderate medium subangular
    blocky structure; friable; common thin brown             Landform: Outwash plains
    (10YR 4/3) clay films on faces of peds; common           Position on the landform: Shoulders
    thin accumulations of iron and manganese; slightly
                                                                                 Composition
    acid; clear smooth boundary.
2Bt3—33 to 42 inches; dark yellowish brown (10YR             Martinsville and similar soils: 90 percent
    4/4) sandy loam; weak coarse prismatic structure         Dissimilar soils: 10 percent
    parting to weak medium subangular blocky;
                                                                             Minor Components
    friable; few thin brown (10YR 4/3) clay films on
    faces of peds; moderately acid; clear smooth             Similar soils:
    boundary.                                                • Soils that have less silt and more sand in the upper
2BC—42 to 48 inches; yellowish brown (10YR 5/4),             part
    stratified silt loam and loam; weak coarse               • Soils that have less sand and more silt in the
    prismatic structure; friable; very few thin brown        subsoil
    (10YR 4/3) clay films lining pores; moderately acid;
                                                             Dissimilar soils:
    clear smooth boundary.
                                                             • The somewhat poorly drained Coffeen and Orion
2C—48 to 72 inches; mottled yellowish brown (10YR
                                                             soils on footslopes
    5/4) and dark grayish brown (10YR 4/2), stratified
                                                             • The well drained Raddle soils on shoulders
    silt loam, loam, and sandy loam; massive; friable;
    slightly acid.                                                    Properties and Qualities of the
                                                                             Martinsville Soil
             Range in Characteristics
                                                             Parent material: Outwash
Depth to the base of the argillic horizon: 40 to 70
                                                             Drainage class: Well drained
    inches
                                                             Slowest permeability within a depth of 40 inches:
Thickness of the solum: Less than 80 inches
                                                                 Moderate
Ap or A horizon:                                             Permeability below a depth of 60 inches: Moderate
    Hue—10YR                                                 Depth to restrictive feature: More than 80 inches
    Value—3 to 5                                             Available water capacity to a depth of 60 inches: About
    Chroma—2 to 6                                                9.7 inches
    Texture—loam, silt loam, fine sandy loam, or             Content of organic matter in the surface layer: 1 to 3
       sandy loam                                                percent
Rock Island County, Illinois                                                                                    77




Shrink-swell potential: Moderate                           Potential for frost action: Moderate
Flooding: None                                             Hazard of corrosion: Moderate for steel and moderate
Accelerated erosion: None or slight                            for concrete
Potential for frost action: Moderate                       Surface runoff class: Medium
Hazard of corrosion: Moderate for steel and moderate       Susceptibility to water erosion: Moderate
    for concrete                                           Susceptibility to wind erosion: Slight
Surface runoff class: Low
                                                                           Interpretive Groups
Susceptibility to water erosion: Moderate
Susceptibility to wind erosion: Slight                     Land capability classification: 4e
                                                           Prime farmland status: Not prime farmland
                Interpretive Groups
                                                           Hydric soil status: Not hydric
Land capability classification: 2e
Prime farmland status: Prime farmland
Hydric soil status: Not hydric                             570D3—Martinsville clay loam, 10 to 18
                                                              percent slopes, severely eroded
570C3—Martinsville clay loam, 5 to 10                                              Setting
   percent slopes, severely eroded                         Landform: Outwash plains
                                                           Position on the landform: Backslopes
                        Setting
                                                                               Composition
Landform: Outwash plains
Position on the landform: Backslopes                       Martinsville and similar soils: 90 percent
                                                           Dissimilar soils: 10 percent
                    Composition
                                                                           Minor Components
Martinsville and similar soils: 90 percent
Dissimilar soils: 10 percent                               Similar soils:
                                                           • Soils that have less silt and more sand in the upper
                Minor Components
                                                           part
Similar soils:                                             • Soils that have less sand and more silt in the subsoil
• Soils that have less silt and more sand in the upper
                                                           Dissimilar soils:
part
                                                           • The somewhat poorly drained Coffeen and Orion
• Soils that have less sand and more silt in the subsoil
                                                           soils on footslopes
Dissimilar soils:                                          • The well drained Raddle soils on shoulders
• The somewhat poorly drained Coffeen and Orion
                                                                    Properties and Qualities of the
soils on footslopes
                                                                           Martinsville Soil
• The well drained Raddle soils on shoulders
                                                           Parent material: Outwash
         Properties and Qualities of the
                                                           Drainage class: Well drained
                Martinsville Soil
                                                           Slowest permeability within a depth of 40 inches:
Parent material: Outwash                                       Moderate
Drainage class: Well drained                               Permeability below a depth of 60 inches: Moderate
Slowest permeability within a depth of 40 inches:          Depth to restrictive feature: More than 80 inches
    Moderate                                               Available water capacity to a depth of 60 inches: About
Permeability below a depth of 60 inches: Moderate              9.7 inches
Depth to restrictive feature: More than 80 inches          Content of organic matter in the surface layer: 0.5 to
Available water capacity to a depth of 60 inches: About        1.0 percent
    9.7 inches                                             Shrink-swell potential: Moderate
Content of organic matter in the surface layer: 0.5 to     Flooding: None
    1.0 percent                                            Accelerated erosion: The surface layer is mostly
Shrink-swell potential: Moderate                               subsoil material.
Flooding: None                                             Potential for frost action: Moderate
Accelerated erosion: The surface layer is mostly           Hazard of corrosion: Moderate for steel and moderate
    subsoil material.                                          for concrete
78                                                                                                    Soil Survey of




Surface runoff class: Medium                                   Value—2 to 5
Susceptibility to water erosion: High                          Chroma—0 to 2
Susceptibility to wind erosion: Slight                         Texture—loam, silt loam, silty clay loam, or clay
                                                                 loam; strata of sandy loam and/or gravel in
                Interpretive Groups
                                                                 some pedons
Land capability classification: 4e
                                                           Cg horizon:
Prime farmland status: Not prime farmland
                                                               Chroma—0 to 2
Hydric soil status: Not hydric
                                                               Texture—stratified, calcareous sandy loam to silty
                                                                 clay loam
Millington Series
Taxonomic classification: Fine-loamy, mixed,               1082A—Millington silt loam, undrained, 0
   superactive, calcareous, mesic Cumulic                     to 2 percent slopes, frequently flooded
   Endoaquolls
                                                                                    Setting
                    Typical Pedon
                                                           Landform: Flood plains
Millington silt loam, undrained, 0 to 2 percent slopes,
                                                                               Composition
frequently flooded; 700 feet south and 940 feet west of
the northeast corner of sec. 25, T. 20 N., R. 4 E.; in     Millington and similar soils: 95 percent
Whiteside County, Illinois; USGS Prophetstown              Dissimilar soils: 5 percent
topographic quadrangle; lat. 41 degrees 41 minutes 50
                                                                           Minor Components
seconds N. and 89 degrees 58 minutes 54 seconds
W., NAD 27:                                                Similar soils:
                                                           • Soils that contain more sand in the subsoil
A—0 to 19 inches; black (10YR 2/1) silt loam, very
                                                           • Soils that are not calcareous
   dark gray (10YR 3/1) dry; moderate fine
                                                           • Soils that consist of marshy organic material
   subangular blocky structure; friable; few snail-shell
   fragments; slightly effervescent; slightly alkaline;    Dissimilar soils:
   clear smooth boundary.                                  • The poorly drained Sawmill soils on toeslopes
Bg—19 to 35 inches; black (10YR 2/1) loam, very dark
                                                           Properties and Qualities of the Millington Soil
   gray (10YR 3/1) dry; weak medium subangular
   blocky structure; friable; few snail-shell fragments;   Parent material: Alluvium
   strongly effervescent; slightly alkaline; clear         Drainage class: Poorly drained
   smooth boundary.                                        Slowest permeability within a depth of 40 inches:
Cg—35 to 60 inches; olive gray (5Y 5/2) loam that has          Moderate
   few thin strata of sandy loam; massive; friable;        Permeability below a depth of 60 inches: Moderate
   common medium prominent strong brown (7.5YR             Depth to restrictive feature: More than 80 inches
   5/8) iron masses and common medium faint dark           Available water capacity to a depth of 60 inches: About
   gray (5Y 4/1) iron depletions in the matrix; few            11.4 inches
   snail-shell fragments; strongly effervescent;           Content of organic matter in the surface layer: 4 to 6
   slightly alkaline.                                          percent
                                                           Shrink-swell potential: Moderate
             Range in Characteristics
                                                           Depth and months of the highest apparent seasonal
Thickness of the mollic epipedon: 24 to 40 inches              high water table: At the surface, November to
Thickness of the solum: 24 to 48 inches                        June
                                                           Ponding depth: 0.2 foot during wet periods
Ap or A horizon:
                                                           Frequency and most likely period of flooding:
    Hue—10YR or N
                                                               Frequent, November to June
    Value—2 or 3
                                                           Potential for frost action: High
    Chroma—0 to 2
                                                           Hazard of corrosion: High for steel and low for
    Texture—loam, silt loam, silty clay loam, or clay
                                                               concrete
       loam
                                                           Surface runoff class: Negligible
Bg horizon:                                                Susceptibility to water erosion: Slight
    Hue—10YR, 2.5Y, 5Y, or N                               Susceptibility to wind erosion: Slight
Rock Island County, Illinois                                                                                       79




                Interpretive Groups                          and either protected from flooding or not
                                                             frequently flooded during the growing season
Land capability classification: 5w
                                                          Hydric soil status: Hydric
Prime farmland status: Not prime farmland
Hydric soil status: Hydric
                                                          Millsdale Series
3082A—Millington silt loam, 0 to 2                        Taxonomic classification: Fine, mixed, active, mesic
   percent slopes, frequently flooded                        Typic Argiaquolls
                                                                             Typical Pedon
                         Setting
                                                          Millsdale silty clay loam, 0 to 2 percent slopes; 1,095
Landform: Flood plains
                                                          feet west and 1,760 feet south of the northeast corner
                    Composition                           of sec. 30, T. 19 N., R. 3 E.; in Rock Island County,
                                                          Illinois; USGS Hillsdale topographic quadrangle; lat. 41
Millington and similar soils: 97 percent
                                                          degrees 36 minutes 32 seconds N. and long. 90
Dissimilar soils: 3 percent
                                                          degrees 11 minutes 41 seconds W., NAD 27:
                Minor Components
                                                          Ap—0 to 8 inches; black (2.5Y 2.5/1) silty clay loam;
Similar soils:                                               moderate very fine and fine granular structure;
• Soils that contain more sand in the subsoil                friable; slightly alkaline; abrupt smooth boundary.
• Soils that are not calcareous                           A—8 to 15 inches; black (2.5Y 2.5/1) silty clay loam;
• Soils that consist of marshy organic material              moderate fine and medium granular structure;
                                                             friable; slightly alkaline; clear smooth boundary.
Dissimilar soils:
                                                          BA—15 to 23 inches; black (2.5Y 2.5/1) silty clay;
• The poorly drained Sawmill soils on toeslopes
                                                             moderate fine and medium subangular blocky
• Well drained soils on footslopes
                                                             structure; firm; discontinuous very dark gray (N
                                                             3/0) organic stains on faces of peds; slightly
Properties and Qualities of the Millington Soil
                                                             alkaline; clear smooth boundary.
Parent material: Alluvium                                 Btg—23 to 27 inches; dark gray (10YR 4/1) silty clay
Drainage class: Poorly drained                               loam; moderate fine and medium subangular
Slowest permeability within a depth of 40 inches:            blocky structure; firm; common fine distinct
    Moderate                                                 yellowish brown (10YR 5/4) redoximorphic
Permeability below a depth of 60 inches: Moderate            features; slightly alkaline; abrupt smooth boundary.
Depth to restrictive feature: More than 80 inches         2R—27 to 60 inches; white (10YR 8/1) limestone;
Available water capacity to a depth of 60 inches: About      strongly effervescent; moderately alkaline.
    11.4 inches
                                                                       Range in Characteristics
Content of organic matter in the surface layer: 4 to 6
    percent                                               Thickness of the mollic epipedon: 10 to 23 inches
Shrink-swell potential: Moderate                          Depth to lithic contact: 20 to 40 inches
Depth and months of the highest apparent seasonal         Thickness of the solum: 20 to 40 inches
    high water table: At the surface, January to May
                                                          Ap, A, and/or BA horizon:
Frequency and most likely period of flooding:
                                                              Hue—10YR, 2.5Y, or N
    Frequent, November to June
                                                              Value—2 or 3
Potential for frost action: High
                                                              Chroma—0 to 2
Hazard of corrosion: High for steel and low for
                                                              Texture—silty clay loam, clay loam, loam, or silt
    concrete
                                                                 loam
Surface runoff class: Negligible
Susceptibility to water erosion: Slight                   Btg or Bt horizon:
Susceptibility to wind erosion: Slight                        Hue—10YR, 2.5Y, 5Y, or N
                                                              Value—3 to 6
                Interpretive Groups
                                                              Chroma—0 to 2 (upper part); 0 to 4 (lower part)
Land capability classification: 3w                            Texture—clay loam, silty clay loam, silty clay, or
Prime farmland status: Prime farmland where drained              clay
80                                                                                                   Soil Survey of




2Btg, 2Bt, 2BCg, and/or 2BC horizon:                                       Interpretive Groups
    Hue—10YR, 2.5Y, or 5Y
                                                           Land capability classification: 3w
    Value—4 to 7
                                                           Prime farmland status: Prime farmland where drained
    Chroma—1 to 4
                                                           Hydric soil status: Hydric
    Texture—clay loam, silty clay loam, silty clay, or
       clay
2C or 2Cg horizon:                                         M-W—Miscellaneous water
   Hue—10YR, 2.5Y, or 5Y
   Value—4 to 7                                                             General Definition
   Chroma—1 to 4
                                                           • This map unit consists of manmade areas that are
   Texture—loam or clay loam
                                                           used for industrial, sanitary, or mining applications and
                                                           that contain water most of the year.
317A—Millsdale silty clay loam, 0 to 2
   percent slopes
                                                           Moline Series
                        Setting
                                                           Taxonomic classification: Fine, smectitic, mesic Vertic
Landform: Lake plains
                                                              Endoaquolls
                    Composition
                                                             Typical Pedon (Official Series Description)
Millsdale and similar soils: 100 percent
                                                           Moline silty clay, 0 to 2 percent slopes, at an elevation
                Minor Components                           of 577 feet; 60 feet north and 2,600 feet west of the
                                                           southeast corner of sec. 16, T. 17 N., R. 1 E.; in Henry
Similar soils:
                                                           County, Illinois; USGS Coal Valley topographic
• Soils that contain less clay in the subsoil
                                                           quadrangle; lat. 41 degrees 27 minutes 30 seconds N.
• Soils that are calcareous
                                                           and long. 90 degrees 23 minutes 00 seconds W., NAD
• Soils that have bedrock at a depth of less than 20
                                                           27:
inches or more than 40 inches
                                                           Ap—0 to 7 inches; black (10YR 2/1) silty clay, dark
Properties and Qualities of the Millsdale Soil
                                                              gray (10YR 4/1) dry; moderate medium
Parent material: Lacustrine deposits                          subangular blocky structure; firm; neutral; clear
Drainage class: Very poorly drained                           smooth boundary.
Slowest permeability within a depth of 40 inches: Slow     A—7 to 14 inches; black (2.5Y 2.5/1) silty clay, very
Permeability below a depth of 60 inches: Slow or              dark gray (10YR 3/1) dry; strong medium
    moderately slow                                           subangular blocky structure; firm; neutral; clear
Depth to restrictive feature: 20 to 40 inches to bedrock      wavy boundary.
    (lithic)                                               Bg1—14 to 24 inches; dark gray (5Y 4/1) clay; strong
Available water capacity to a depth of 60 inches: About       medium and coarse subangular blocky structure;
    4.3 inches                                                very firm; common medium black (2.5Y 2.5/1)
Content of organic matter in the surface layer: 4 to 7        organic coatings on faces of peds; few medium
    percent                                                   prominent strong brown (7.5YR 5/6) masses of
Shrink-swell potential: High                                  iron; neutral; clear wavy boundary.
Depth and months of the highest apparent seasonal          Bg2—24 to 33 inches; grayish brown (2.5Y 5/2) clay;
    high water table: At the surface, January to              strong medium and coarse subangular blocky
    June                                                      structure; very firm; common medium distinct light
Ponding depth: 0.5 foot during wet periods                    brownish gray (10YR 6/2) iron depletions;
Flooding: None                                                common coarse prominent reddish brown (5YR
Accelerated erosion: None or slight                           4/4) masses of iron; violently effervescent; slightly
Potential for frost action: High                              alkaline; abrupt wavy boundary.
Hazard of corrosion: High for steel and low for            2B1—33 to 52 inches; reddish brown (5YR 4/4) clay;
    concrete                                                  strong medium and coarse subangular blocky
Surface runoff class: Medium                                  structure; very firm; common gray (10YR 6/1)
Susceptibility to water erosion: Slight                       calcium carbonate concretions; many coarse
Susceptibility to wind erosion: Very slight                   prominent grayish brown (2.5Y 5/2) iron
Rock Island County, Illinois                                                                                      81




   depletions; violently effervescent; moderately            1654A—Moline silty clay, undrained, 0 to 2
   alkaline; clear wavy boundary.                               percent slopes, frequently flooded
2B2—52 to 65 inches; reddish brown (5YR 4/4) clay;
   strong medium and coarse subangular blocky                                         Setting
   structure; very firm; many gray (10YR 6/1) calcium
                                                             Landform: Flood plains
   carbonate concretions; moderately effervescent;
   slightly alkaline; gradual wavy boundary.                                     Composition
2BC—65 to 75 inches; reddish brown (5YR 4/4) clay;
                                                             Moline and similar soils: 100 percent
   several thin (less than 1 cm) olive gray (5Y 5/2)
   bands of silt loam in the lower part; weak coarse                         Minor Components
   subangular blocky structure; firm; moderately
                                                             Similar soils:
   effervescent; slightly alkaline; clear wavy
                                                             • Soils that have a surface layer less than 10 inches
   boundary.
                                                             thick
3Cg—75 to 100 inches; light brownish gray (2.5Y 6/2)
                                                             • Soils that are underlain by bedrock within a depth of
   silt loam; massive; friable; many coarse prominent
                                                             60 inches
   brownish yellow (10YR 6/8) masses of iron;
                                                             • Soils that contain less clay throughout
   moderately effervescent; slightly alkaline.
                                                               Properties and Qualities of the Moline Soil
              Range in Characteristics
                                                             Parent material: Clayey alluvium
Thickness of the mollic epipedon: 10 to 20 inches            Drainage class: Poorly drained
Depth to free carbonates: 20 to 50 inches                    Slowest permeability within a depth of 40 inches: Slow
Thickness of the solum: 45 to 80 inches                      Permeability below a depth of 60 inches: Slow
                                                             Depth to restrictive feature: More than 80 inches
Ap and A horizons:                                           Available water capacity to a depth of 60 inches: About
    Hue—10YR, 2.5Y, or N                                         6.3 inches
    Value—2 or 3                                             Content of organic matter in the surface layer: 2 to 4
    Chroma—0 to 2                                                percent
    Texture—silty clay or silty clay loam                    Shrink-swell potential: Very high
    Reaction—slightly acid to slightly alkaline              Depth and months of the highest apparent seasonal
                                                                 high water table: At the surface, November to
Bg horizon:
                                                                 June
    Hue—5Y or 2.5Y
                                                             Ponding depth: 0.2 foot during wet periods
    Value—3 to 5
                                                             Frequency and most likely period of flooding:
    Chroma—1 or 2
                                                                 Frequent, November to June
    Texture—clay or silty clay
                                                             Potential for frost action: High
    Reaction—slightly acid to slightly alkaline
                                                             Hazard of corrosion: High for steel and low for concrete
2B and 2BC horizons:                                         Surface runoff class: Low
    Hue—2.5YR or 5YR                                         Susceptibility to water erosion: Slight
    Value—3 to 5                                             Susceptibility to wind erosion: Moderate
    Chroma—2 to 6
                                                                             Interpretive Groups
    Texture—clay or silty clay; strata of silt, silt loam,
      and silty clay loam in some pedons                     Land capability classification: 5w
    Reaction—neutral to strongly alkaline                    Prime farmland status: Not prime farmland
                                                             Hydric soil status: Hydric
3C horizon (if it occurs):
   Hue—10YR, 2.5Y, or 5Y
   Value—3 to 6
   Chroma—1 or 2                                             7654A—Moline silty clay, 0 to 2 percent
   Texture—silt loam or silty clay loam; strata of finer        slopes, rarely flooded
      or coarser textures in some pedons below a
                                                                                      Setting
      depth of 50 inches
   Reaction—slightly alkaline to strongly alkaline           Landform: Flood plains
82                                                                                                 Soil Survey of




                    Composition                           Ap—0 to 7 inches; black (10YR 2/1) silt loam, dark
                                                             grayish brown (10YR 4/2) dry; moderate fine
Moline and similar soils: 100 percent
                                                             granular structure; very friable; common very fine
                                                             and fine roots throughout; neutral; abrupt smooth
                Minor Components
                                                             boundary.
Similar soils:                                            A—7 to 13 inches; very dark gray (10YR 3/1) silt loam,
• Soils that have a surface layer less than 10 inches        dark grayish brown (10YR 4/2) dry; moderate fine
thick                                                        granular structure; very friable; common very fine
• Soils that are underlain by bedrock within a depth of      and fine roots throughout; neutral; clear smooth
60 inches                                                    boundary.
• Soils that contain less clay throughout                 AB—13 to 20 inches; mixed very dark grayish brown
                                                             (10YR 3/2) and brown (10YR 4/3) silt loam, dark
  Properties and Qualities of the Moline Soil                grayish brown (10YR 4/2) dry; moderate fine
                                                             subangular blocky structure parting to weak fine
Parent material: Clayey lacustrine deposits over
                                                             granular; friable; common very fine roots
    stratified alluvium
                                                             throughout; few faint very dark gray (10YR 3/1)
Drainage class: Poorly drained
                                                             organic coatings on faces of peds; few faint dark
Slowest permeability within a depth of 40 inches: Slow
                                                             grayish brown (10YR 4/2) clay films on faces of
Permeability below a depth of 60 inches: Slow
                                                             peds; neutral; clear smooth boundary.
Depth to restrictive feature: More than 80 inches
                                                          Bt1—20 to 28 inches; brown (10YR 4/3) silty clay
Available water capacity to a depth of 60 inches: About
                                                             loam; moderate medium subangular blocky
    6.3 inches
                                                             structure; friable; few fine roots between peds; few
Content of organic matter in the surface layer: 2 to 4
                                                             faint dark grayish brown (10YR 4/2) clay films on
    percent
                                                             faces of peds; common faint very dark grayish
Shrink-swell potential: Very high
                                                             brown (10YR 3/2) organic coatings on faces of
Depth and months of the highest apparent seasonal
                                                             peds; common dark manganese stains; neutral;
    high water table: At the surface, January to May
                                                             clear smooth boundary.
Ponding depth: 0.5 foot during wet periods
                                                          Bt2—28 to 38 inches; brown (10YR 5/3) silty clay
Frequency and most likely period of flooding: Rare,
                                                             loam; moderate medium subangular blocky
    November to June
                                                             structure; friable; few fine roots between peds;
Potential for frost action: High
                                                             common distinct dark grayish brown (2.5Y 4/2)
Hazard of corrosion: High for steel and low for
                                                             clay films on faces of peds; few fine distinct
    concrete
                                                             yellowish brown (10YR 5/6) and faint pale brown
Surface runoff class: Negligible
                                                             (10YR 6/3) iron masses in the matrix; common
Susceptibility to water erosion: Slight
                                                             dark manganese stains; neutral; clear smooth
Susceptibility to wind erosion: Moderate
                                                             boundary.
                Interpretive Groups                       Btg—38 to 50 inches; light brownish gray (2.5Y 6/2)
                                                             silty clay loam; moderate medium subangular
Land capability classification: 3w
                                                             blocky structure; friable; few very fine roots
Prime farmland status: Prime farmland where drained
                                                             between peds; common prominent grayish brown
Hydric soil status: Hydric
                                                             (10YR 5/2) clay films on faces of peds; common
                                                             fine prominent yellowish brown (10YR 5/6) and
Muscatune Series                                             dark yellowish brown (10YR 4/6) iron masses in
                                                             the matrix; common dark manganese stains;
Taxonomic classification: Fine-silty, mixed,                 slightly acid; clear smooth boundary.
   superactive, mesic Aquic Argiudolls                    BCg—50 to 60 inches; light brownish gray (2.5Y 6/2)
                                                             silt loam; weak medium subangular blocky
                   Typical Pedon
                                                             structure; friable; common medium prominent
Muscatune silt loam, 0 to 2 percent slopes; 2,500 feet       yellowish brown (10YR 5/6) and dark yellowish
west and 2,240 feet north of the southeast corner of         brown (10YR 4/6) iron masses in the matrix;
sec. 29, T. 9 N., R. 1 W.; in Warren County, Illinois;       common dark manganese stains; slightly acid;
USGS Greenbush topographic quadrangle; lat. 40               clear smooth boundary.
degrees 44 minutes 11 seconds N. and long. 90             Cg—60 to 80 inches; light brownish gray (2.5Y 6/2) silt
degrees 31 minutes 46 seconds W., NAD 27:                    loam; massive; friable; many medium prominent
Rock Island County, Illinois                                                                                  83




    yellowish brown (10YR 5/6) and dark yellowish       Drainage class: Somewhat poorly drained
    brown (10YR 4/6) iron masses in the matrix; few     Slowest permeability within a depth of 40 inches:
    fine round very dark brown (10YR 2/2) soft              Moderate
    masses of iron and manganese; neutral.              Permeability below a depth of 60 inches: Moderate
                                                        Depth to restrictive feature: More than 80 inches
             Range in Characteristics
                                                        Available water capacity to a depth of 60 inches: About
Thickness of the mollic epipedon: 10 to 20 inches           12.4 inches
Thickness of the loess: More than 60 inches             Content of organic matter in the surface layer: 3.5 to
Depth to free carbonates: More than 40 inches               5.0 percent
Thickness of the solum: 40 to 64 inches                 Shrink-swell potential: Moderate
                                                        Depth and months of the highest apparent seasonal
Ap or A horizon:
                                                            high water table: 1 foot, January to May
    Hue—10YR
                                                        Flooding: None
    Value—2 or 3
                                                        Accelerated erosion: None or slight
    Chroma—1 or 2
                                                        Potential for frost action: High
    Texture—silt loam or silty clay loam
                                                        Hazard of corrosion: High for steel and moderate for
Bt horizon:                                                 concrete
    Hue—10YR or 2.5Y                                    Surface runoff class: Low
    Value—4 to 6                                        Susceptibility to water erosion: Slight
    Chroma—2 to 4                                       Susceptibility to wind erosion: Slight
    Texture—silty clay loam
                                                                        Interpretive Groups
C horizon:
                                                        Land capability classification: 1
   Hue—10YR or 2.5Y
                                                        Prime farmland status: Prime farmland
   Value—5 or 6
                                                        Hydric soil status: Not hydric
   Chroma—2 to 4
   Texture—silt loam or silty clay loam

                                                        Niota Series
51A—Muscatune silt loam, 0 to 2 percent
   slopes                                               Taxonomic classification: Fine, mixed, superactive,
                                                           mesic Vertic Albaqualfs
                         Setting
                                                                           Typical Pedon
Landform: Ground moraines
Position on the landform: Summits                       Niota silt loam, 0 to 2 percent slopes; 600 feet north
                                                        and 1,320 feet east of the southwest corner of sec. 30,
                    Composition
                                                        T. 19 N., R. 3 E.; in Whiteside County, Illinois; USGS
Muscatune and similar soils: 95 percent                 Hillsdale topographic quadrangle; lat. 41 degrees 36
Dissimilar soils: 5 percent                             minutes 01 second N. and long. 90 degrees 12
                                                        minutes 17 seconds W., NAD 27:
                Minor Components
                                                        A—0 to 7 inches; black (10YR 2/1) silt loam, gray
Similar soils:
                                                           (10YR 5/1) dry; moderate very fine and fine
• Soils that have a surface layer less than 10 inches
                                                           granular structure; friable; many fine roots
thick; on slopes of 2 to 5 percent near the head of
                                                           throughout; neutral; clear smooth boundary.
drainageways
                                                        E—7 to 14 inches; mixed grayish brown (10YR 5/2)
• Soils that have a seasonal high water table below a
                                                           and dark grayish brown (10YR 4/2) silt loam, light
depth of 2 feet
                                                           brownish gray (10YR 6/2) dry; moderate thin platy
Dissimilar soils:                                          structure parting to moderate fine granular; friable;
• The poorly drained Denny and Sable soils in              common fine roots throughout; common distinct
depressions                                                light gray (10YR 7/1) (dry) clay depletions on
• The well drained Osco soils on shoulders                 faces of peds; few fine dark concretions of iron
                                                           and manganese in the matrix; strongly acid;
         Properties and Qualities of the
                                                           abrupt smooth boundary.
                Muscatune Soil
                                                        2Bt—14 to 24 inches; reddish brown (5YR 4/4) silty
Parent material: Loess                                     clay; moderate medium prismatic structure parting
84                                                                                                  Soil Survey of




    to moderate medium subangular blocky; very firm;       3Cg horizon:
    few fine roots between peds; many distinct grayish        Texture—silt loam; strata of loam, clay loam,
    brown (2.5Y 5/2) clay films on faces of peds; very           sandy loam, silty clay loam, or loamy fine sand
    strongly acid; clear smooth boundary.                        in some pedons
2Btg1—24 to 37 inches; mixed gray (5Y 5/1) and light
    gray (5Y 6/1) silty clay loam; moderate medium
    prismatic structure parting to moderate medium         261A—Niota silt loam, 0 to 2 percent
    subangular blocky; firm; few fine roots between           slopes
    peds; common distinct dark gray (5Y 4/1) clay                                  Setting
    films on faces of peds; few fine dark concretions of
                                                           Landform: Lake plains
    iron and manganese in the matrix; few fine and
                                                           Position on the landform: Summits
    medium prominent yellowish red (5Y 4/6) masses
    of iron in the matrix; very strongly acid; gradual                         Composition
    smooth boundary.
                                                           Niota and similar soils: 98 percent
3Btg2—37 to 53 inches; light gray (5Y 6/1) silt loam;
                                                           Dissimilar soils: 2 percent
    weak coarse prismatic structure parting to weak
    medium subangular blocky; friable; common                              Minor Components
    distinct reddish gray (5YR 5/2) clay films on faces
                                                           Similar soils:
    of peds; many prominent black (7.5YR 2.5/1) iron
                                                           • Soils that have a thicker surface layer
    and manganese stains on faces of peds; many
                                                           • Soils that have a seasonal high water table at a
    fine dark concretions of iron and manganese in
                                                           depth of more than 1 foot
    the matrix; few fine and medium prominent
    yellowish red (5Y 4/6) masses of iron in the matrix;   Dissimilar soils:
    very strongly acid; clear smooth boundary.             • The well drained Coyne soils on backslopes
3Cg—53 to 60 inches; light gray (5Y 6/1) silt loam;        • The well drained Joslin and Raddle soils on
    massive; friable; many fine dark concretions of        summits
    iron and manganese in the matrix; many fine and
                                                              Properties and Qualities of the Niota Soil
    medium prominent yellowish red (5Y 4/6) masses
    of iron in the matrix; slightly acid.                  Parent material: Glaciolacustrine deposits
                                                           Drainage class: Poorly drained
             Range in Characteristics
                                                           Slowest permeability within a depth of 40 inches: Very
Thickness of the solum: 40 to 60 inches                        slow
Thickness of the loess: Less than 20 inches                Permeability below a depth of 60 inches: Moderately
Depth to lacustrine sediments: 10 to 20 inches                 rapid
                                                           Depth to restrictive feature: More than 80 inches
Ap or A horizon:
                                                           Available water capacity to a depth of 60 inches: About
    Hue—10YR
                                                               8.3 inches
    Value—2 or 3
                                                           Content of organic matter in the surface layer: 1 to 3
    Chroma—1 or 2
                                                               percent
Eg horizon:                                                Shrink-swell potential: High
    Hue—10YR or 2.5Y                                       Depth and months of the highest apparent seasonal
    Value—4 to 6                                               high water table: At the surface, January to June
    Chroma—1 to 3                                          Ponding depth: 0.2 foot during wet periods
                                                           Flooding: None
2Bt or 2Btg horizon:
                                                           Accelerated erosion: None or slight
    Hue—2.5YR to 5Y or N
                                                           Potential for frost action: High
    Value—4 to 6
                                                           Hazard of corrosion: High for steel and high for
    Chroma—0 to 4
                                                               concrete
    Texture—silty clay, clay, or silty clay loam
                                                           Surface runoff class: Negligible
3Btg or 3BCg horizon (if it occurs):                       Susceptibility to water erosion: Slight
    Hue—7.5YR to 5Y or N                                   Susceptibility to wind erosion: Slight
    Value—4 to 6
                                                                           Interpretive Groups
    Chroma—0 to 2
    Texture—silt loam, silty clay loam, or loam            Land capability classification: 2w
Rock Island County, Illinois                                                                                   85




Prime farmland status: Prime farmland where drained       741F—Oakville fine sand, 20 to 30 percent
Hydric soil status: Hydric                                   slopes
                                                                                 Setting
Oakville Series                                           Landform: Dunes
                                                          Position on the landform: Backslopes
Taxonomic classification: Mixed, mesic Typic
                                                                              Composition
   Udipsamments
                                                          Oakville and similar soils: 95 percent
                   Typical Pedon
                                                          Dissimilar soils: 5 percent
Oakville fine sand, 7 to 15 percent slopes; 716 feet
                                                                          Minor Components
south and 1,056 feet east of the northwest corner of
sec. 18, T. 17 N., R. 6 E.; in Bureau County, Illinois;   Similar soils:
USGS Mineral topographic quadrangle; lat. 41 degrees      • Soils that have a darker surface layer
27 minutes 54 seconds N. and long. 89 degrees 51          • Soils that are calcareous within a depth of 60 inches
minutes 12 seconds W., NAD 27:                            • Soils that contain more gravel in all or part of the
                                                          profile
Ap—0 to 5 inches; brown (10YR 4/3) fine sand,
                                                          Dissimilar soils:
   yellowish brown (10YR 5/4) dry; weak fine
                                                          • Poorly drained soils on toeslopes
   granular structure; very friable; common fine roots
                                                          • The well drained Tell soils on shoulders and summits
   throughout; neutral; abrupt smooth boundary.
Bw—5 to 23 inches; strong brown (7.5YR 5/6) fine           Properties and Qualities of the Oakville Soil
   sand; weak medium subangular blocky structure;
                                                          Parent material: Eolian sands
   very friable; few fine roots throughout; neutral;
                                                          Drainage class: Excessively drained
   clear smooth boundary.
                                                          Slowest permeability within a depth of 40 inches:
BC—23 to 36 inches; yellowish brown (10YR 5/6) fine
                                                              Rapid
   sand; very weak medium subangular blocky
                                                          Permeability below a depth of 60 inches: Rapid
   structure; very friable; few fine roots throughout;
                                                          Depth to restrictive feature: More than 80 inches
   neutral; clear smooth boundary.
                                                          Available water capacity to a depth of 60 inches: About
C—36 to 60 inches; yellowish brown (10YR 5/6) fine
                                                              4.1 inches
   sand; single grain; loose; neutral.
                                                          Content of organic matter in the surface layer: 0.5 to
                                                              2.0 percent
             Range in Characteristics
                                                          Shrink-swell potential: Low
Thickness of the solum: 22 to 40 inches                   Flooding: None
                                                          Accelerated erosion: None or slight
Ap or A horizon:                                          Potential for frost action: Low
    Hue—10YR                                              Hazard of corrosion: Low for steel and moderate for
    Value—3 or 4                                              concrete
    Chroma—1 to 4                                         Surface runoff class: Low
    Texture—fine sand, sand, loamy fine sand, or          Susceptibility to water erosion: Slight
       loamy sand                                         Susceptibility to wind erosion: High
                                                                          Interpretive Groups
Bw horizon:
   Hue—10YR or 7.5YR                                      Land capability classification: 7s
   Value—4 to 6                                           Prime farmland status: Not prime farmland
   Chroma—3 or 4                                          Hydric soil status: Not hydric
   Texture—fine sand, loamy sand, or sand

C horizon:                                                917C2—Oakville-Tell complex, 5 to 10
   Hue—10YR                                                  percent slopes, eroded
   Value—4 to 7
                                                                                 Setting
   Chroma—3 to 6
   Texture—fine sand                                      Landform: Outwash plains
86                                                                                                 Soil Survey of




Position on the landform: Oakville—summits and            Accelerated erosion: The surface layer has been
    shoulders; Tell—shoulders and backslopes                  thinned by erosion.
                                                          Potential for frost action: High
                    Composition
                                                          Hazard of corrosion: Moderate for steel and moderate
Oakville and similar soils: 50 percent                        for concrete
Tell and similar soils: 40 percent                        Surface runoff class: Medium
Dissimilar soils: 10 percent                              Susceptibility to water erosion: High
                                                          Susceptibility to wind erosion: Slight
                Minor Components
                                                                          Interpretive Groups
Similar soils:
• Soils that have a darker surface layer                  Land capability classification: Oakville—6s; Tell—3e
• Soils that are calcareous within a depth of 60 inches   Prime farmland status: Not prime farmland
• Soils that contain more gravel in all or part of the    Hydric soil status: Oakville—not hydric; Tell—not
profile                                                       hydric
• Soils that have more clay in the upper part
Dissimilar soils:                                         917D2—Oakville-Tell complex, 10 to 18
• The somewhat poorly drained Joy soils on                   percent slopes, eroded
footslopes
                                                                                 Setting
 Properties and Qualities of the Oakville Soil
                                                          Landform: Outwash plains
Parent material: Eolian sands
                                                          Position on the landform: Oakville—upper and middle
Drainage class: Excessively drained
                                                              parts of backslopes; Tell—middle and lower parts
Slowest permeability within a depth of 40 inches:
                                                              of backslopes
    Rapid
Permeability below a depth of 60 inches: Rapid                                Composition
Depth to restrictive feature: More than 80 inches
                                                          Oakville and similar soils: 50 percent
Available water capacity to a depth of 60 inches: About
                                                          Tell and similar soils: 45 percent
    4.6 inches
                                                          Dissimilar soils: 5 percent
Content of organic matter in the surface layer: 0.5 to
    2.0 percent                                                           Minor Components
Shrink-swell potential: Low
                                                          Similar soils:
Flooding: None
                                                          • Soils that have a darker surface layer
Accelerated erosion: The surface layer has been
                                                          • Soils that are calcareous within a depth of 60 inches
    thinned by erosion.
                                                          • Soils that contain more gravel in all or part of the
Potential for frost action: Low
                                                          profile
Hazard of corrosion: Low for steel and moderate for
                                                          • Soils that have more clay in the upper part
    concrete
Surface runoff class: Very low                            Dissimilar soils:
Susceptibility to water erosion: Slight                   • The somewhat poorly drained Joy soils on
Susceptibility to wind erosion: High                      footslopes
                                                          • Poorly drained soils on toeslopes
     Properties and Qualities of the Tell Soil
                                                           Properties and Qualities of the Oakville Soil
Parent material: Loess over outwash
Drainage class: Well drained                              Parent material: Eolian sands
Slowest permeability within a depth of 40 inches:         Drainage class: Excessively drained
    Moderate                                              Slowest permeability within a depth of 40 inches:
Permeability below a depth of 60 inches: Rapid                Rapid
Depth to restrictive feature: More than 80 inches         Permeability below a depth of 60 inches: Rapid
Available water capacity to a depth of 60 inches: About   Depth to restrictive feature: More than 80 inches
    7.4 inches                                            Available water capacity to a depth of 60 inches: About
Content of organic matter in the surface layer: 1 to 3        4.3 inches
    percent                                               Content of organic matter in the surface layer: 0.5 to
Shrink-swell potential: Moderate                              2.0 percent
Flooding: None                                            Shrink-swell potential: Low
Rock Island County, Illinois                                                                                        87




Flooding: None                                               friable; many thin strata of brown (10YR 4/3) and
Accelerated erosion: The surface layer has been              very dark gray (10YR 3/1) silt loam; neutral; abrupt
    thinned by erosion.                                      smooth boundary.
Potential for frost action: Low                           C1—5 to 15 inches; dark grayish brown (10YR 4/2) silt
Hazard of corrosion: Low for steel and moderate for          loam; massive; friable; many thin strata of pale
    concrete                                                 brown (10YR 6/3) and yellowish brown (10YR 5/4)
Surface runoff class: Very low                               silt loam; few fine prominent brown (7.5YR 4/4)
Susceptibility to water erosion: Slight                      masses of iron in the matrix; neutral; clear wavy
Susceptibility to wind erosion: High                         boundary.
                                                          C2—15 to 29 inches; dark grayish brown (10YR 4/2)
    Properties and Qualities of the Tell Soil
                                                             silt loam; massive; friable; many thin strata of dark
Parent material: Loess over outwash                          yellowish brown (10YR 4/4), yellowish brown
Drainage class: Well drained                                 (10YR 5/6), and pale brown (10YR 6/3) silt loam;
Slowest permeability within a depth of 40 inches:            few very dark gray (10YR 3/1) wormcasts; few fine
    Moderate                                                 prominent brown (7.5YR 4/4) masses of iron in the
Permeability below a depth of 60 inches: Rapid               matrix; neutral; abrupt wavy boundary.
Depth to restrictive feature: More than 80 inches         Ab1—29 to 39 inches; black (2.5Y 2.5/1) silt loam;
Available water capacity to a depth of 60 inches: About      weak thick platy structure parting to weak medium
    8.1 inches                                               and fine subangular blocky; friable; neutral; clear
Content of organic matter in the surface layer: 1 to 3       smooth boundary.
    percent                                               Ab2—39 to 51 inches; black (2.5Y 2.5/1) silty clay
Shrink-swell potential: Moderate                             loam; strong medium and fine angular blocky
Flooding: None                                               structure; friable; neutral; clear smooth boundary.
Accelerated erosion: The surface layer has been           Ab3—51 to 60 inches; very dark gray (10YR 3/1) silty
    thinned by erosion.                                      clay loam; moderate medium and fine subangular
Potential for frost action: High                             blocky structure; friable; neutral.
Hazard of corrosion: Moderate for steel and moderate
                                                                       Range in Characteristics
    for concrete
Surface runoff class: Medium                              Depth to the dark buried soil: 20 to 40 inches
Susceptibility to water erosion: High                     Thickness of the surface layer: 5 to 10 inches
Susceptibility to wind erosion: Slight
                                                          Ap or A horizon:
                Interpretive Groups                           Hue—10YR
                                                              Value—3 to 6
Land capability classification: Oakville—6s; Tell—4e
                                                              Chroma—2 or 3
Prime farmland status: Not prime farmland
                                                              Texture—silt loam; stratified in some pedons
Hydric soil status: Oakville—not hydric; Tell—not
    hydric                                                C horizon:
                                                             Hue—10YR
                                                             Value—3 to 5
Orion Series                                                 Chroma—2 or 3
                                                             Texture—silt loam; stratified in some pedons
Taxonomic classification: Coarse-silty, mixed,
                                                          Ab horizon:
   superactive, nonacid, mesic Aquic Udifluvents
                                                              Hue—10YR or 2.5Y
                   Typical Pedon                              Value—2 or 3
                                                              Chroma—1 or 2
Orion silt loam, 0 to 2 percent slopes, frequently
                                                              Texture—silty clay loam or silt loam; stratified in
flooded; 270 feet south and 1,000 feet east of the
                                                                some pedons
northwest corner of sec. 17, T. 22 N., R. 6 E.; in
Whiteside County, Illinois; USGS Milledgeville
topographic quadrangle; 41 degrees 54 minutes 06          3415A—Orion silt loam, 0 to 2 percent
seconds N. and long. 89 degrees 50 minutes 13                slopes, frequently flooded
seconds W., NAD 27:
                                                                                   Setting
A—0 to 5 inches; dark grayish brown (10YR 4/2) silt
  loam, light brownish gray (10YR 6/2) dry; massive;      Landform: Flood plains
88                                                                                                    Soil Survey of




                    Composition                                             Minor Components
Orion and similar soils: 95 percent                        Similar soils:
Dissimilar soils: 5 percent                                • Soils that contain more sand in the lower part
                                                           • Soils that have a buried surface layer at a depth of
                Minor Components
                                                           more than 40 inches
Similar soils:                                             • Soils that have a seasonal high water table within a
• Soils that contain more sand in the lower part           depth of 1 foot
• Soils that have a buried surface layer at a depth of
                                                             Properties and Qualities of the Orion Soil
more than 40 inches
• Soils that have a seasonal high water table within a     Parent material: Alluvium
depth of 1 foot                                            Drainage class: Somewhat poorly drained
                                                           Slowest permeability within a depth of 40 inches:
Dissimilar soils:
                                                               Moderate
• The poorly drained Sawmill soils in the lower
                                                           Permeability below a depth of 60 inches: Moderate
positions on flood plains
                                                           Depth to restrictive feature: More than 80 inches
     Properties and Qualities of the Orion Soil            Available water capacity to a depth of 60 inches: About
                                                               12.7 inches
Parent material: Alluvium
                                                           Content of organic matter in the surface layer: 1 to 3
Drainage class: Somewhat poorly drained
                                                               percent
Slowest permeability within a depth of 40 inches:
                                                           Shrink-swell potential: Low
    Moderate
                                                           Depth and months of the highest apparent seasonal
Permeability below a depth of 60 inches: Moderate
                                                               high water table: 1 foot, January to May
Depth to restrictive feature: More than 80 inches
                                                           Frequency and most likely period of flooding: Rare,
Available water capacity to a depth of 60 inches: About
                                                               November to June
    12.3 inches
                                                           Accelerated erosion: None or slight
Content of organic matter in the surface layer: 1 to 3
                                                           Potential for frost action: High
    percent
                                                           Hazard of corrosion: High for steel and low for
Shrink-swell potential: Low
                                                               concrete
Depth and months of the highest apparent seasonal
                                                           Surface runoff class: Low
    high water table: 1 foot, January to May
                                                           Susceptibility to water erosion: Slight
Frequency and most likely period of flooding:
                                                           Susceptibility to wind erosion: Slight
    Frequent, November to June
Potential for frost action: High                                           Interpretive Groups
Hazard of corrosion: High for steel and low for concrete
                                                           Land capability classification: 2w
Surface runoff class: Low
                                                           Prime farmland status: Prime farmland
Susceptibility to water erosion: Slight
                                                           Hydric soil status: Not hydric
Susceptibility to wind erosion: Slight
                Interpretive Groups
Land capability classification: 3w                         802B—Orthents, loamy, undulating
Prime farmland status: Prime farmland where
                                                                                   Setting
    protected from flooding or not frequently flooded
    during the growing season                              Landform: Ground moraines
Hydric soil status: Not hydric
                                                                                Composition
                                                           Orthents and similar soils: 85 percent
7415A—Orion silt loam, 0 to 2 percent                      Dissimilar soils: 15 percent
   slopes, rarely flooded
                                                                            Minor Components
                         Setting
                                                           Similar soils:
Landform: Flood plains                                     • Soils that typically have a surface layer of silt loam or
                                                           silty clay loam
                    Composition
                                                           • Soils that have a perched seasonal high water table
Orion and similar soils: 100 percent                       within a depth of 60 inches
Rock Island County, Illinois                                                                                      89




Dissimilar soils:                                               moderate medium and coarse granular structure;
• The somewhat poorly drained Muscatune soils on                friable; common fine roots; strongly acid; clear
summits                                                         smooth boundary.
                                                             BA—14 to 20 inches; dark yellowish brown (10YR 3/4)
   Properties and Qualities of the Orthents
                                                                and dark brown (10YR 3/3) silt loam, brown (10YR
Parent material: Mine spoil or earthy fill                      5/3) dry; weak fine subangular blocky structure;
Drainage class: Well drained                                    friable; common fine roots; few distinct light
Slowest permeability within a depth of 40 inches:               brownish gray (10YR 6/2) (dry) silt coatings on
    Moderately slow                                             faces of peds; strongly acid; clear smooth
Permeability below a depth of 60 inches: Moderately             boundary.
    slow                                                     Bt1—20 to 26 inches; brown (10YR 4/3) silty clay
Depth to restrictive feature: More than 80 inches               loam; moderate fine subangular blocky structure;
Available water capacity to a depth of 60 inches: About         friable; few fine roots; few distinct gray (10YR 6/1)
    10.9 inches                                                 (dry) silt coatings and common faint dark brown
Content of organic matter in the surface layer: 0.5 to          (10YR 3/3) clay films on faces of peds; strongly
    2.0 percent                                                 acid; clear smooth boundary.
Shrink-swell potential: Moderate                             Bt2—26 to 37 inches; dark yellowish brown (10YR 4/4)
Flooding: None                                                  silty clay loam; moderate medium subangular
Accelerated erosion: None or slight                             blocky structure; firm; few fine roots; common
Potential for frost action: Moderate                            distinct light brownish gray (10YR 6/2) (dry) silt
Hazard of corrosion: Moderate for steel and moderate            coatings and many faint dark yellowish brown
    for concrete                                                (10YR 4/4) clay films on faces of peds; common
Surface runoff class: Medium                                    fine faint brown (10YR 5/3) and common medium
Susceptibility to water erosion: Moderate                       prominent strong brown (7.5YR 5/8)
Susceptibility to wind erosion: Slight                          redoximorphic concentrations; many prominent
                                                                very dark gray (N 3/0) and dark brown (7.5YR 3/2)
                Interpretive Groups
                                                                manganese concretions; strongly acid; clear
Land capability classification: 2e                              smooth boundary.
Prime farmland status: Not prime farmland                    Bt3—37 to 45 inches; light yellowish brown (10YR 6/4)
Hydric soil status: Not hydric                                  silty clay loam; moderate coarse subangular
                                                                blocky structure; friable; few fine roots; many faint
                                                                dark yellowish brown (10YR 4/4) clay films on
Osco Series                                                     faces of peds; common fine distinct light brownish
                                                                gray (10YR 6/2) redoximorphic depletions and few
Taxonomic classification: Fine-silty, mixed,
                                                                medium prominent strong brown (7.5YR 5/8)
   superactive, mesic Typic Argiudolls
                                                                redoximorphic concentrations; strongly acid;
Taxadjunct features: The Osco soil in map unit 86C2
                                                                gradual smooth boundary.
   has a thinner dark surface layer than is defined as
                                                             BC—45 to 55 inches; yellowish brown (10YR 5/4) and
   the range for the series. This soil is classified as a
                                                                brown (10YR 4/3) silty clay loam; weak coarse
   Mollic Hapludalf.
                                                                angular blocky structure; friable; few fine distinct
  Typical Pedon (Official Series Description)                   light brownish gray (10YR 6/2) redoximorphic
                                                                depletions; strongly acid; gradual smooth
Osco silt loam, 2 to 5 percent slopes, at an elevation
                                                                boundary.
of 858 feet; 316 feet north and 88 feet west of the
                                                             C—55 to 60 inches; yellowish brown (10YR 5/4) and
southeast corner of sec. 23, T. 24 N., R. 6 E.; in Carroll
                                                                brown (10YR 4/3) silt loam; massive; friable; many
County, Illinois; USGS Lanark topographic quadrangle;
                                                                fine distinct yellowish brown (10YR 5/6)
lat. 42 degrees 03 minutes 15 seconds N. and long. 89
                                                                redoximorphic concentrations and common
degrees 45 minutes 52 seconds W., NAD 27:
                                                                medium distinct grayish brown (10YR 5/2)
Ap—0 to 10 inches; very dark brown (10YR 2/2) silt              redoximorphic depletions; moderately acid.
   loam, very dark grayish brown (10YR 3/2) dry;
                                                                         Range in Characteristics
   moderate fine granular structure; friable; common
   fine roots; slightly acid; abrupt smooth boundary.        Thickness of the mollic epipedon: 10 to 18 inches
A—10 to 14 inches; very dark grayish brown (10YR             Thickness of the solum: 40 to more than 60 inches
   3/2) silt loam, dark grayish brown (10YR 4/2) dry;        Depth to free carbonates: More than 48 inches
90                                                                                                 Soil Survey of




Ap or A horizon:                                          Potential for frost action: High
    Hue—10YR                                              Hazard of corrosion: Moderate for steel and moderate
    Value—2 or 3                                              for concrete
    Chroma—1 or 2                                         Surface runoff class: Low
    Texture—silt loam                                     Susceptibility to water erosion: Slight
                                                          Susceptibility to wind erosion: Slight
Bt horizon:
    Hue—10YR                                                              Interpretive Groups
    Value—4 to 6
                                                          Land capability classification: 2e
    Chroma—3 or 4
                                                          Prime farmland status: Prime farmland
    Texture—silty clay loam or silt loam
                                                          Hydric soil status: Not hydric
C or Cg horizon:
    Hue—10YR or 2.5Y
    Value—4 or 5                                          86C2—Osco silt loam, 5 to 10 percent
    Chroma—3 to 6                                            slopes, eroded
    Texture—silt loam
                                                                                 Setting
86B—Osco silt loam, 2 to 5 percent                        Landform: Ground moraines
   slopes                                                 Position on the landform: Backslopes and shoulders
                        Setting                                               Composition
Landform: Ground moraines                                 Osco and similar soils: 90 percent
Position on the landform: Summits and shoulders           Dissimilar soils: 10 percent
                    Composition                                           Minor Components
Osco and similar soils: 90 percent                        Similar soils:
Dissimilar soils: 10 percent                              • Soils that have more sand in the lower part
                                                          • Soils that have a seasonal high water table within a
                Minor Components
                                                          depth of 4 feet
Similar soils:
                                                          Dissimilar soils:
• Soils that have more sand in the lower part
                                                          • The poorly drained Denny and Sable soils in
• Soils that have a seasonal high water table within a
                                                          depressions
depth of 4 feet
                                                             Properties and Qualities of the Osco Soil
Dissimilar soils:
• The poorly drained Denny and Sable soils in             Parent material: Loess
depressions                                               Drainage class: Well drained
                                                          Slowest permeability within a depth of 40 inches:
     Properties and Qualities of the Osco Soil
                                                              Moderate
Parent material: Loess                                    Permeability below a depth of 60 inches: Moderate
Drainage class: Well drained                              Depth to restrictive feature: More than 80 inches
Slowest permeability within a depth of 40 inches:         Available water capacity to a depth of 60 inches: About
    Moderate                                                  11.7 inches
Permeability below a depth of 60 inches: Moderate         Content of organic matter in the surface layer: 2 to 3
Depth to restrictive feature: More than 80 inches             percent
Available water capacity to a depth of 60 inches: About   Shrink-swell potential: Moderate
    11.9 inches                                           Depth and months of the highest apparent seasonal
Content of organic matter in the surface layer: 3 to 4        high water table: 4 feet, February to April
    percent                                               Flooding: None
Shrink-swell potential: Moderate                          Accelerated erosion: The surface layer has been
Depth and months of the highest apparent seasonal             thinned by erosion.
    high water table: 4 feet, February to April           Potential for frost action: High
Flooding: None                                            Hazard of corrosion: Moderate for steel and moderate
Accelerated erosion: None or slight                           for concrete
Rock Island County, Illinois                                                                                   91




Surface runoff class: Medium                                 masses in the matrix; neutral; clear smooth
Susceptibility to water erosion: Moderate                    boundary.
Susceptibility to wind erosion: Slight                    Bg—43 to 50 inches; grayish brown (2.5Y 5/2) silt loam;
                                                             weak coarse subangular blocky structure; friable;
                Interpretive Groups
                                                             few distinct very dark grayish brown (10YR 3/2)
Land capability classification: 3e                           organic coatings in root channels; common medium
Prime farmland status: Not prime farmland                    prominent yellowish brown (10YR 5/6) and few
Hydric soil status: Not hydric                               medium prominent brown (7.5YR 4/4) iron masses
                                                             in the matrix; neutral; clear smooth boundary.
                                                          Cg—50 to 60 inches; light brownish gray (2.5Y 6/2) silt
Otter Series                                                 loam; massive; friable; common fine prominent
                                                             yellowish brown (10YR 5/6) iron masses in the
Taxonomic classification: Fine-silty, mixed,                 matrix; neutral.
   superactive, mesic Cumulic Endoaquolls
                                                                       Range in Characteristics
                   Typical Pedon
                                                          Thickness of the mollic epipedon: 24 to 50 inches
Otter silt loam, 0 to 2 percent slopes; 1,960 feet west   Thickness of the solum: 24 to 50 inches
and 2,540 feet south of the northeast corner of sec.
                                                          Ap, A, or AB horizon:
35, T. 22 N., R. 5 E.; in Whiteside County, Illinois;
                                                              Hue—7.5YR, 10YR, 2.5Y, or N
USGS Morrison topographic quadrangle; lat. 41
                                                              Value—2 or 3
degrees 51 minutes 06 seconds N. and long. 89
                                                              Chroma—0 to 2
degrees 53 minutes 18 seconds W., NAD 27:
                                                              Texture—silt loam
Ap—0 to 10 inches; black (10YR 2/1) silt loam, dark
                                                          Bg horizon:
   gray (10YR 4/1) dry; moderate medium granular
                                                              Hue—7.5YR, 10YR, 2.5Y, or N
   structure; friable; slightly acid; abrupt smooth
                                                              Value—2 to 6
   boundary.
                                                              Chroma—0 to 4
A1—10 to 16 inches; black (10YR 2/1) silt loam, dark
                                                              Texture—silt loam, loam, sandy loam, or silty clay
   gray (10YR 4/1) dry; weak fine subangular blocky
                                                                loam
   structure parting to moderate medium granular;
   friable; slightly acid; clear smooth boundary.         Cg horizon:
A2—16 to 21 inches; black (2.5Y 2.5/1) silt loam, very        Hue—10YR, 2.5Y, 5Y, or N
   dark gray (10YR 3/1) dry; weak fine subangular             Value—2 to 6
   blocky structure parting to moderate medium                Chroma—0 to 4
   granular; friable; few fine distinct grayish brown         Texture—silt loam or loam; strata of silty clay loam
   (2.5Y 5/2) iron depletions and few fine prominent            or sandy loam in some pedons
   yellowish brown (10YR 5/8) iron masses in the
   matrix; few fine prominent dark reddish brown
   (5YR 2.5/2) coatings of iron on faces of peds;         1076A—Otter silt loam, undrained, 0 to 2
   slightly acid; clear smooth boundary.                     percent slopes, frequently flooded
A3—21 to 35 inches; black (2.5Y 2.5/1) mucky silt
                                                                                   Setting
   loam, black (2.5Y 2.5/1) dry; weak medium
   subangular blocky structure; friable; few fine         Landform: Flood plains
   prominent strong brown (7.5YR 4/6) iron masses
                                                                              Composition
   in the matrix; few fine prominent dark reddish
   brown (5YR 2.5/2) coatings of iron on faces of         Otter and similar soils: 90 percent
   peds; slightly acid; clear smooth boundary.            Dissimilar soils: 10 percent
AB—35 to 43 inches; very dark gray (10YR 3/1) silt
                                                                          Minor Components
   loam, gray (10YR 5/1) dry; weak coarse
   subangular blocky structure; friable; few fine         Similar soils:
   prominent dark reddish brown (5YR 2.5/2)               • Soils that are calcareous within a depth of 60 inches
   coatings of iron on faces of peds; common              • Soils that contain more clay in all or part of the
   medium faint dark gray (10YR 4/1) iron depletions      profile
   and few fine prominent brown (7.5YR 4/4) iron          • Soils that consist of marshy organic material
92                                                                                                 Soil Survey of




Dissimilar soils:                                         Slowest permeability within a depth of 40 inches:
• The poorly drained Sawmill soils on toeslopes               Moderate
                                                          Permeability below a depth of 60 inches: Moderate
     Properties and Qualities of the Otter Soil
                                                          Depth to restrictive feature: More than 80 inches
Parent material: Alluvium                                 Available water capacity to a depth of 60 inches: About
Drainage class: Poorly drained                                13.1 inches
Slowest permeability within a depth of 40 inches:         Content of organic matter in the surface layer: 3 to 5
    Moderate                                                  percent
Permeability below a depth of 60 inches: Moderate         Shrink-swell potential: Moderate
Depth to restrictive feature: More than 80 inches         Depth and months of the highest apparent seasonal
Available water capacity to a depth of 60 inches: About       high water table: At the surface, January to May
    12.5 inches                                           Ponding depth: 0.2 foot during wet periods
Content of organic matter in the surface layer: 3 to 5    Frequency and most likely period of flooding:
    percent                                                   Frequent, November to June
Shrink-swell potential: Moderate                          Potential for frost action: High
Depth and months of the highest apparent seasonal         Hazard of corrosion: High for steel and low for
    high water table: At the surface, November to June        concrete
Ponding depth: 0.2 foot during wet periods                Surface runoff class: Negligible
Frequency and most likely period of flooding:             Susceptibility to water erosion: Slight
    Frequent, November to June                            Susceptibility to wind erosion: Slight
Potential for frost action: High
                                                                          Interpretive Groups
Hazard of corrosion: High for steel and low for
    concrete                                              Land capability classification: 3w
Surface runoff class: Negligible                          Prime farmland status: Prime farmland where drained
Susceptibility to water erosion: Slight                       and either protected from flooding or not
Susceptibility to wind erosion: Slight                        frequently flooded during the growing season
                                                          Hydric soil status: Hydric
                Interpretive Groups
Land capability classification: 5w
Prime farmland status: Not prime farmland                 7076A—Otter silt loam, 0 to 2 percent
Hydric soil status: Hydric                                   slopes, rarely flooded
                                                                                   Setting
3076A—Otter silt loam, 0 to 2 percent                     Landform: Flood plains
   slopes, frequently flooded
                                                                              Composition
                         Setting
                                                          Otter and similar soils: 97 percent
Landform: Flood plains                                    Dissimilar soils: 3 percent
                    Composition                                           Minor Components
Otter and similar soils: 85 percent                       Similar soils:
Dissimilar soils: 15 percent                              • Soils that are calcareous within a depth of 60 inches
                                                          • Soils that contain more clay in all or part of the
                Minor Components
                                                          profile
Similar soils:
                                                          Dissimilar soils:
• Soils that are calcareous within a depth of 60 inches
                                                          • Well drained soils on footslopes
• Soils that contain more clay in all or part of the
                                                          • The poorly drained Sawmill soils on toeslopes
profile
                                                             Properties and Qualities of the Otter Soil
Dissimilar soils:
• The poorly drained Sawmill soils on toeslopes           Parent material: Alluvium
                                                          Drainage class: Poorly drained
     Properties and Qualities of the Otter Soil
                                                          Slowest permeability within a depth of 40 inches:
Parent material: Alluvium                                     Moderate
Drainage class: Poorly drained                            Permeability below a depth of 60 inches: Moderate
Rock Island County, Illinois                                                                                    93




Depth to restrictive feature: More than 80 inches           Properties and Qualities of the Psamments
Available water capacity to a depth of 60 inches: About
                                                           Parent material: Outwash or eolian sands
    12.9 inches
                                                           Drainage class: Excessively drained
Content of organic matter in the surface layer: 3 to 10
                                                           Slowest permeability within a depth of 40 inches:
    percent
                                                               Rapid
Shrink-swell potential: Moderate
                                                           Permeability below a depth of 60 inches: Rapid
Depth and months of the highest apparent seasonal
                                                           Depth to restrictive feature: More than 80 inches
    high water table: At the surface, January to May
                                                           Available water capacity to a depth of 60 inches: About
Ponding depth: 0.2 foot during wet periods
                                                               4.2 inches
Frequency and most likely period of flooding: Rare,
                                                           Content of organic matter in the surface layer: 0.0 to
    November to June
                                                               0.5 percent
Potential for frost action: High
                                                           Shrink-swell potential: Low
Hazard of corrosion: High for steel and low for concrete
                                                           Flooding: None
Surface runoff class: Negligible
                                                           Accelerated erosion: None or slight
Susceptibility to water erosion: Slight
                                                           Potential for frost action: Not rated
Susceptibility to wind erosion: Slight
                                                           Surface runoff class: Low
                Interpretive Groups                        Susceptibility to water erosion: Slight
                                                           Susceptibility to wind erosion: Very high
Land capability classification: 2w
Prime farmland status: Prime farmland where drained                        Interpretive Groups
Hydric soil status: Hydric
                                                           Land capability classification: Not assigned
                                                           Prime farmland status: Not prime farmland
864—Pits, quarries                                         Hydric soil status: Not hydric

                 General Definition
                                                           Raddle Series
• This map unit consists of open excavations from
which soil and the underlying material have been           Taxonomic classification: Fine-silty, mixed,
removed and in which bedrock is exposed. Limestone            superactive, mesic Typic Hapludolls
was the principal quarry rock.
                                                                              Typical Pedon
                                                           Raddle silt loam, 0 to 2 percent slopes; 1,780 feet west
865—Pits, gravel                                           and 2,020 feet north of the southeast corner of sec.
                                                           23, T. 19 N., R. 4 E.; in Whiteside County, Illinois;
                 General Definition                        Spring Hill topographic quadrangle; lat. 41 degrees 37
                                                           minutes 03 seconds N. and long. 90 degrees 00
• This map unit consists of open excavations from
                                                           minutes 13 seconds W., NAD 27:
which soil and the underlying material have been
removed and used, without crushing, as a source of         Ap—0 to 10 inches; black (10YR 2/1) silt loam, dark
sand or gravel.                                               gray (10YR 4/1) dry; weak fine and medium
                                                              granular structure; friable; slightly acid; abrupt
                                                              smooth boundary.
800C—Psamments, sloping                                    A1—10 to 16 inches; very dark grayish brown (10YR
                                                              3/2) silt loam, grayish brown (10YR 5/2) dry;
                        Setting
                                                              moderate medium subangular blocky structure
Landform: Outwash plains                                      parting to weak fine granular; friable; many faint
Position on the landform: Backslopes                          very dark gray (10YR 3/1) organic coatings on
                                                              faces of peds; moderately acid; clear smooth
                    Composition
                                                              boundary.
Psamments and similar soils: 100 percent                   A2—16 to 21 inches; dark brown (10YR 3/3) silt loam,
                                                              brown (10YR 5/3) dry; moderate fine and medium
                Minor Components
                                                              subangular blocky structure; friable; clay films on
Similar soils:                                                faces of peds; very dark grayish brown (10YR 3/2)
• The excessively drained Oakville soils on shoulders         organic coatings on faces of peds; moderately
and backslopes                                                acid; clear smooth boundary.
94                                                                                                Soil Survey of




BA—21 to 26 inches; brown (10YR 4/3) silt loam;          430A—Raddle silt loam, 0 to 2 percent
   moderate medium subangular blocky structure;             slopes
   friable; common faint dark brown (10YR 3/3)
                                                                                Setting
   organic coatings on faces of peds; moderately
   acid; clear smooth boundary.                          Landform: Stream terraces
Bt1—26 to 34 inches; dark yellowish brown (10YR 4/4)     Position on the landform: Summits
   silt loam; moderate medium subangular blocky
   structure; friable; common faint brown (10YR 4/3)                         Composition
   clay films on faces of peds; moderately acid;
                                                         Raddle and similar soils: 95 percent
   gradual smooth boundary.
                                                         Dissimilar soils: 5 percent
Bt2—34 to 51 inches; dark yellowish brown (10YR 4/4)
   silt loam; moderate coarse subangular blocky
                                                                         Minor Components
   structure; friable; few faint brown (10YR 4/3) clay
   films on faces of peds; moderately acid; clear        Similar soils:
   smooth boundary.                                      • Soils that have a surface layer either less than 10
BC—51 to 61 inches; yellowish brown (10YR 5/4) silt      inches thick or more than 24 inches thick
   loam; weak coarse angular blocky structure;           • Soils that have a seasonal high water table within a
   friable; few fine black (7.5YR 2.5/1) iron-           depth of 60 inches
   manganese stains on faces of peds; few fine           • Soils that have less silt and more sand in the surface
   distinct light brownish gray (10YR 6/2) iron          layer
   depletions; moderately acid; clear smooth
                                                         Dissimilar soils:
   boundary.
                                                         • Somewhat poorly drained soils on footslopes
C—61 to 80 inches; yellowish brown (10YR 5/4) silt
   loam; massive; friable; few fine prominent black
                                                           Properties and Qualities of the Raddle Soil
   (7.5YR 2.5/1) soft masses of iron-manganese in
   the matrix; few fine distinct light brownish gray     Parent material: Slope alluvium
   (10YR 6/2) iron depletions; slightly acid.            Drainage class: Well drained
                                                         Slowest permeability within a depth of 40 inches:
            Range in Characteristics                         Moderate
                                                         Permeability below a depth of 60 inches: Moderate
Thickness of the mollic epipedon: 10 to 24 inches
                                                         Depth to restrictive feature: More than 80 inches
Thickness of the solum: 40 to more than 80 inches
                                                         Available water capacity to a depth of 60 inches: About
                                                             13 inches
Ap or A horizon:
                                                         Content of organic matter in the surface layer: 2 to 4
    Hue—10YR
                                                             percent
    Value—2 or 3
                                                         Shrink-swell potential: Low
    Chroma—1 to 3
                                                         Flooding: None
    Texture—silt loam
                                                         Accelerated erosion: None or slight
Bt or Bw horizon:                                        Potential for frost action: High
    Hue—7.5YR or 10YR                                    Hazard of corrosion: Moderate for steel and moderate
    Value—3 to 6                                             for concrete
    Chroma—3 or 4                                        Surface runoff class: Low
    Texture—silt loam                                    Susceptibility to water erosion: Slight
                                                         Susceptibility to wind erosion: Slight
C horizon:
   Hue—7.5YR or 10YR
                                                                         Interpretive Groups
   Value—3 to 6
   Chroma—2 to 4                                         Land capability classification: 1
   Texture—silt loam; thin strata of sandy loam,         Prime farmland status: Prime farmland
       loam, clay loam, or silty clay loam in some       Hydric soil status: Not hydric
       pedons
Rock Island County, Illinois                                                                                     95




430B—Raddle silt loam, 2 to 5 percent                      Radford Series
   slopes
                                                           Taxonomic classification: Fine-silty, mixed,
                        Setting
                                                              superactive, mesic Fluvaquentic Hapludolls
Landform: Terraces
                                                                              Typical Pedon
Position on the landform: Shoulders and backslopes
                                                           Radford silt loam, 0 to 2 percent slopes, occasionally
                    Composition                            flooded; 1,109 feet west and 1,254 feet south of the
                                                           northeast corner of sec. 23, T. 17 N., R. 8 E.; in Bureau
Raddle and similar soils: 89 percent
                                                           County, Illinois; USGS Buda Northeast topographic
Dissimilar soils: 11 percent
                                                           quadrangle; lat. 41 degrees 26 minutes 54 seconds N.
                                                           and long. 89 degrees 32 minutes 04 seconds W., NAD
                Minor Components
                                                           27:
Similar soils:
                                                           Ap—0 to 9 inches; very dark grayish brown (10YR 3/2)
• Soils that have a surface layer either less than 10
                                                              silt loam, grayish brown (10YR 5/2) dry; moderate
inches thick or more than 24 inches thick
                                                              medium granular structure; friable; common fine
• Soils that have a seasonal high water table within a
                                                              roots; moderately acid; abrupt smooth boundary.
depth of 60 inches
                                                           A—9 to 21 inches; very dark grayish brown (10YR 3/2)
• Soils that have less silt and more sand in the surface
                                                              silt loam, grayish brown (10YR 5/2) dry; moderate
layer
                                                              medium granular structure; friable; common fine
                                                              roots; few fine dark masses of iron and
Dissimilar soils:
                                                              manganese throughout; slightly acid; gradual
• The somewhat poorly drained Orion soils and other
                                                              smooth boundary.
somewhat poorly drained soils; on footslopes
                                                           C—21 to 29 inches; stratified very dark gray (10YR
                                                              3/1) silt loam and brown (10YR 5/3) silty clay
  Properties and Qualities of the Raddle Soil
                                                              loam; weak medium subangular blocky structure;
Parent material: Alluvium                                     friable; few fine roots; common fine dark masses
Drainage class: Well drained                                  of iron and manganese throughout; slightly acid;
Slowest permeability within a depth of 40 inches:             clear smooth boundary.
    Moderate                                               Ab1—29 to 36 inches; black (10YR 2/1) silty clay loam;
Permeability below a depth of 60 inches: Moderate             moderate medium subangular blocky structure;
Depth to restrictive feature: More than 80 inches             friable; few fine roots; few medium faint very dark
Available water capacity to a depth of 60 inches: About       grayish brown (10YR 3/2) masses of iron and
    12.8 inches                                               manganese in the matrix; few very fine dark
Content of organic matter in the surface layer: 2 to 4        masses of iron and manganese throughout;
    percent                                                   slightly acid; clear smooth boundary.
Shrink-swell potential: Low                                Ab2—36 to 43 inches; black (10YR 2/1) silty clay loam;
Flooding: None                                                weak medium subangular blocky structure; friable;
Accelerated erosion: None or slight                           few fine faint very dark grayish brown (10YR 3/2)
Potential for frost action: High                              masses of iron and manganese in the matrix; few
Hazard of corrosion: Moderate for steel and moderate          very fine dark masses of iron and manganese
    for concrete                                              throughout; neutral; clear smooth boundary.
Surface runoff class: Low                                  Bgb—43 to 60 inches; black (10YR 2/1) silty clay loam;
Susceptibility to water erosion: Moderate                     moderate medium prismatic structure parting to
Susceptibility to wind erosion: Slight                        moderate medium subangular blocky; friable; few
                                                              fine faint dark gray (10YR 4/1) iron depletions in
                Interpretive Groups                           the matrix; few very fine dark masses of iron and
                                                              manganese throughout; neutral.
Land capability classification: 2e
                                                                        Range in Characteristics
Prime farmland status: Prime farmland
Hydric soil status: Not hydric                             Thickness of the mollic epipedon: 10 to 24 inches
96                                                                                                   Soil Survey of




Depth to the buried soil: 20 to 40 inches                  Content of organic matter in the surface layer: 2 to 4
                                                               percent
Ap or A horizon:
                                                           Shrink-swell potential: Moderate
    Value—2 or 3
                                                           Depth and months of the highest apparent seasonal
    Chroma—1 or 2
                                                               high water table: 1 foot, January to May
C horizon:                                                 Frequency and most likely period of flooding:
   Hue—10YR                                                    Frequent, November to June
   Value—2 to 6                                            Potential for frost action: High
   Chroma—1 or 2                                           Hazard of corrosion: High for steel and moderate for
   Texture—silt loam                                           concrete
                                                           Surface runoff class: Low
Ab horizon:
                                                           Susceptibility to water erosion: Slight
    Hue—10YR or N
                                                           Susceptibility to wind erosion: Slight
    Value—2 or 3
    Chroma—0 or 1                                                          Interpretive Groups
    Texture—silt loam, silty clay loam, clay loam, or
                                                           Land capability classification: 3w
      loam
                                                           Prime farmland status: Prime farmland where
Bgb horizon (if it occurs):                                    protected from flooding or not frequently flooded
   Hue—10YR, 2.5Y, 5Y, or N                                    during the growing season
   Value—3 to 6                                            Hydric soil status: Not hydric
   Chroma—0 to 2


3074A—Radford silt loam, 0 to 2 percent                    Rozetta Series
   slopes, frequently flooded                              Taxonomic classification: Fine-silty, mixed,
                                                              superactive, mesic Typic Hapludalfs
                         Setting
                                                             Typical Pedon (Official Series Description)
Landform: Flood plains
                                                           Rozetta silt loam, 0 to 2 percent slopes, at an elevation
                    Composition
                                                           of 890 feet; 150 feet south and 500 feet east of the
Radford and similar soils: 95 percent                      center of sec. 18, T. 27 N., R. 6 E.; in Stephenson
Dissimilar soils: 5 percent                                County, Illinois; USGS Pearl City topographic
                                                           quadrangle; lat. 42 degrees 20 minutes 00 seconds N.
                Minor Components
                                                           and long. 89 degrees 51 minutes 19 seconds W., NAD
Similar soils:                                             27:
• Soils that have a buried surface layer within a depth
                                                           A—0 to 4 inches; very dark gray (10YR 3/1) silt loam,
of 20 inches
                                                              gray (10YR 6/1) dry; weak medium granular
• Soils that have more sand and less silt in the control
                                                              structure; friable; many fine roots throughout;
section
                                                              moderately acid; clear wavy boundary.
• Soils that have a seasonal high water table within a
                                                           E—4 to 11 inches; dark grayish brown (10YR 4/2) silt
depth of 1 foot
                                                              loam; weak medium platy structure; friable; many
Dissimilar soils:                                             fine roots throughout; strongly acid; clear smooth
• Soils that are less frequently flooded                      boundary.
• The poorly drained Sawmill soils on flood plains         BE—11 to 14 inches; brown (10YR 4/3) silty clay loam;
                                                              weak medium subangular blocky structure; firm;
 Properties and Qualities of the Radford Soil
                                                              many fine roots between peds; few faint brown
Parent material: Alluvium                                     (10YR 5/3) (dry) clay depletions on faces of peds;
Drainage class: Somewhat poorly drained                       strongly acid; clear smooth boundary.
Slowest permeability within a depth of 40 inches:          Bt1—14 to 21 inches; dark yellowish brown (10YR 4/4)
    Moderate                                                  silty clay loam; moderate fine and medium
Permeability below a depth of 60 inches: Moderate             subangular blocky structure; firm; many fine roots
Depth to restrictive feature: More than 80 inches             between peds; many faint brown (10YR 5/3) clay
Available water capacity to a depth of 60 inches: About       films on faces of peds; strongly acid; clear smooth
    12.3 inches                                               boundary.
Rock Island County, Illinois                                                                                   97




Bt2—21 to 39 inches; brown (10YR 5/3) silty clay                            Composition
   loam; moderate medium and coarse subangular
                                                        Rozetta and similar soils: 98 percent
   blocky structure; firm; many faint dark yellowish
                                                        Dissimilar soils: 2 percent
   brown (10YR 4/4) clay films on faces of peds; few
   medium faint grayish brown (10YR 5/2) iron                           Minor Components
   depletions; common medium faint light yellowish
                                                        Similar soils:
   brown (10YR 6/4) and brown (10YR 4/3) masses
                                                        • Soils that have a darker surface layer
   of iron in the matrix; strongly acid; clear smooth
                                                        • Soils that do not have a seasonal high water table
   boundary.
                                                        within a depth of 6 feet
Bt3—39 to 50 inches; yellowish brown (10YR 5/4) silty
   clay loam; weak coarse subangular blocky             Dissimilar soils:
   structure; firm; few faint brown (10YR 4/3) clay     • The somewhat poorly drained Atterberry and
   films on faces of peds; common medium distinct       Stronghurst soils on shoulders
   grayish brown (10YR 5/2) iron depletions;            • The poorly drained Denny soils in depressions
   common medium faint pale brown (10YR 6/3)
                                                         Properties and Qualities of the Rozetta Soil
   masses of iron in the matrix; moderately acid;
   clear smooth boundary.                               Parent material: Loess
C—50 to 60 inches; yellowish brown (10YR 5/4) silt      Drainage class: Well drained
   loam; massive; friable; common medium distinct       Slowest permeability within a depth of 40 inches:
   dark grayish brown (10YR 4/2) iron depletions;           Moderate
   slightly acid.                                       Permeability below a depth of 60 inches: Moderate
                                                        Depth to restrictive feature: More than 80 inches
             Range in Characteristics
                                                        Available water capacity to a depth of 60 inches: About
Thickness of the solum: 42 to 72 inches                     12.4 inches
                                                        Content of organic matter in the surface layer: 1 to 3
Ap or A horizon:
                                                            percent
    Hue—10YR
                                                        Shrink-swell potential: Moderate
    Value—3 to 5
                                                        Depth and months of the highest apparent seasonal
    Chroma—1 to 3
                                                            high water table: 4 feet, February to April
    Texture—silt loam
                                                        Flooding: None
E horizon:                                              Accelerated erosion: None or slight
    Hue—10YR                                            Potential for frost action: High
    Value—4 to 6                                        Hazard of corrosion: Moderate for steel and moderate
    Chroma—2 or 3                                           for concrete
    Texture—silt loam                                   Surface runoff class: Low
                                                        Susceptibility to water erosion: Slight
Bt horizon:
                                                        Susceptibility to wind erosion: Slight
    Hue—7.5YR or 10YR
    Value—4 to 6                                                        Interpretive Groups
    Chroma—3 to 6
                                                        Land capability classification: 1
    Texture—silty clay loam
                                                        Prime farmland status: Prime farmland
C horizon:                                              Hydric soil status: Not hydric
   Hue—10YR
   Value—4 to 6
   Chroma—2 to 6                                        279B—Rozetta silt loam, 2 to 5 percent
   Texture—silt loam or silty clay loam                    slopes
                                                                               Setting
279A—Rozetta silt loam, 0 to 2 percent                  Landform: Ground moraines
   slopes                                               Position on the landform: Summits and shoulders
                        Setting                                             Composition
Landform: Ground moraines                               Rozetta and similar soils: 91 percent
Position on the landform: Summits                       Dissimilar soils: 9 percent
98                                                                                                    Soil Survey of




                Minor Components                               medium granular structure; firm; moderately acid;
                                                               abrupt smooth boundary.
Similar soils:
                                                           A—8 to 19 inches; black (10YR 2/1) silty clay loam,
• Soils that have a darker surface layer
                                                               dark gray (10YR 4/1) dry; moderate very fine
• Soils that have do not have a seasonal high water
                                                               angular blocky structure; firm; few fine rounded
table within a depth of 6 feet
                                                               dark concretions of iron and manganese oxides;
Dissimilar soils:                                              slightly acid; clear smooth boundary.
• The somewhat poorly drained Stronghurst soils on         AB—19 to 23 inches; very dark gray (10YR 3/1) silty
summits                                                        clay loam, grayish brown (10YR 5/2) dry;
• The well drained Hickory soils on backslopes                 moderate fine angular blocky structure; firm; few
                                                               faint dark grayish brown (10YR 3/2) organic
 Properties and Qualities of the Rozetta Soil
                                                               coatings on faces of peds; few fine dark rounded
Parent material: Loess                                         concretions of iron and manganese; clear smooth
Drainage class: Well drained                                   boundary.
Slowest permeability within a depth of 40 inches:          Bg—23 to 29 inches; dark gray (10YR 4/1) silty clay
    Moderate                                                   loam; moderate fine and medium subangular
Permeability below a depth of 60 inches: Moderate              blocky structure; firm; common faint very dark gray
Depth to restrictive feature: More than 80 inches              (10YR 3/1) organic coatings on faces of peds;
Available water capacity to a depth of 60 inches: About        common fine and medium dark rounded
    12.3 inches                                                concretions of iron and manganese oxides;
Content of organic matter in the surface layer: 1 to 3         common medium distinct brown (10YR 5/3)
    percent                                                    masses of iron in the matrix; few medium faint
Shrink-swell potential: Moderate                               dark grayish brown (10YR 4/2) iron depletions;
Depth and months of the highest apparent seasonal              neutral; clear smooth boundary.
    high water table: 4 feet, February to April            Btg1—29 to 38 inches; grayish brown (2.5Y 5/2) silty
Flooding: None                                                 clay loam; moderate medium and coarse
Accelerated erosion: None or slight                            subangular blocky structure; firm; few distinct dark
Potential for frost action: High                               gray (10YR 4/1) clay films on faces of peds; many
Hazard of corrosion: Moderate for steel and moderate           fine and medium dark rounded concretions of iron
    for concrete                                               and manganese; many medium prominent
Surface runoff class: Low                                      yellowish brown (10YR 5/6) masses of iron in the
Susceptibility to water erosion: Moderate                      matrix; neutral; clear wavy boundary.
Susceptibility to wind erosion: Slight                     Btg2—38 to 47 inches; gray (N 5/0) silt loam; weak
                                                               medium prismatic structure parting to weak
                Interpretive Groups
                                                               medium and coarse angular blocky; firm; few
Land capability classification: 2e                             prominent grayish brown (10YR 5/2) clay films on
Prime farmland status: Prime farmland                          faces of peds; common fine dark rounded
Hydric soil status: Not hydric                                 concretions of iron and manganese; many
                                                               medium prominent yellowish brown (10YR 5/6)
                                                               masses of iron in the matrix; slightly alkaline;
Sable Series                                                   gradual smooth boundary.
                                                           Cg—47 to 60 inches; gray (N 5/0) silt loam; massive;
Taxonomic classification: Fine-silty, mixed,                   friable; many fine prominent yellowish brown
   superactive, mesic Typic Endoaquolls                        (10YR 5/6) masses of iron in the matrix; slightly
                                                               effervescent; slightly alkaline.
  Typical Pedon (Official Series Description)
                                                                       Range in Characteristics
Sable silty clay loam, 0 to 2 percent slopes; 1,281 feet
south and 97 feet west of the northeast corner of sec.     Thickness of the mollic epipedon: 12 to 24 inches
14, T. 9 N., R. 3 W.; in Warren County, Illinois; USGS     Thickness of the solum: 40 to 60 inches
Kirkwood East topographic quadrangle; lat. 40 degrees
                                                           Ap or A horizon:
46 minutes 30 seconds N. and long. 90 degrees 41
                                                               Hue—10YR to 5Y or N
minutes 32 seconds W., NAD 27:
                                                               Value—2 or 3
Ap—0 to 8 inches; black (10YR 2/1) silty clay loam,            Chroma—0 or 1
   dark gray (10YR 4/1) dry; moderate fine and                 Texture—silty clay loam or silt loam
Rock Island County, Illinois                                                                                        99




Bg or Btg horizon:                                        Hazard of corrosion: High for steel and low for
    Hue—10YR to 5Y or N                                       concrete
    Value—3 to 6                                          Surface runoff class: Negligible
    Chroma—0 to 2                                         Susceptibility to water erosion: Slight
    Texture—silty clay loam or silt loam                  Susceptibility to wind erosion: Very slight
C horizon:                                                                Interpretive Groups
   Hue—10YR to 5Y or N
                                                          Land capability classification: 2w
   Value—4 to 6
                                                          Prime farmland status: Prime farmland where drained
   Chroma—0 to 2
                                                          Hydric soil status: Hydric
   Texture—silt loam or silty clay loam


68A—Sable silty clay loam, 0 to 2 percent                 Saude Series
   slopes                                                 Taxonomic classification: Coarse-loamy over sandy or
                        Setting                              sandy-skeletal, mixed, superactive, mesic Typic
                                                             Hapludolls
Landform: Ground moraines
Position on the landform: Summits                                             Typical Pedon
                    Composition                           Saude loam, 0 to 2 percent slopes; 2,563 feet west
                                                          and 1,363 feet north of the southeast corner of sec.
Sable and similar soils: 90 percent
                                                          10, T. 20 N., R. 2 E.; in Rock Island County, Illinois;
Dissimilar soils: 10 percent
                                                          USGS Cordova topographic quadrangle; lat. 41
                Minor Components                          degrees 43 minutes 59 seconds N. and long. 90
                                                          degrees 15 minutes 22 seconds W., NAD 27:
Similar soils:
• Soils that have a seasonal high water table at a        Ap—0 to 9 inches; very dark gray (10YR 3/1) loam;
depth of more than 1 foot                                    moderate medium subangular blocky structure;
• Soils that are calcareous in the lower part                friable; moderately acid; clear smooth boundary.
• Soils that have less clay in the surface layer and      A—9 to 14 inches; very dark gray (10YR 3/1) loam;
more clay in the subsoil                                     weak coarse subangular blocky structure parting
                                                             to moderate fine and medium granular; friable;
Dissimilar soils:
                                                             moderately acid; clear smooth boundary.
• The moderately well drained Buckhart soils on
                                                          BA—14 to 22 inches; very dark gray (10YR 3/1), very
shoulders
                                                             dark grayish brown (10YR 3/2), and dark brown
• The well drained Osco soils on summits
                                                             (7.5YR 3/2) loam; moderate medium prismatic
  Properties and Qualities of the Sable Soil                 structure parting to moderate medium subangular
                                                             blocky; friable; strongly acid; clear smooth
Parent material: Loess
                                                             boundary.
Drainage class: Poorly drained
                                                          Bw—22 to 29 inches; brown (7.5YR 4/4) and dark
Slowest permeability within a depth of 40 inches:
                                                             brown (7.5YR 3/4) loam; weak coarse subangular
    Moderate
                                                             blocky structure; friable; moderate discontinuous
Permeability below a depth of 60 inches: Moderate
                                                             dark brown (7.5YR 3/2) organo-clay coatings on
Depth to restrictive feature: More than 80 inches
                                                             faces of peds; strongly acid; clear smooth boundary.
Available water capacity to a depth of 60 inches: About
                                                          2C—29 to 50 inches; yellowish brown (10YR 5/4) and
    11.9 inches
                                                             dark brown (10YR 3/3) medium and coarse sand
Content of organic matter in the surface layer: 5 to 6
                                                             and fine gravel; single grain; moderately acid.
    percent
Shrink-swell potential: Moderate                                       Range in Characteristics
Depth and months of the highest apparent seasonal
                                                          Depth to sand and gravel: 18 to 36 inches
    high water table: At the surface, January to May
Ponding depth: 0.2 foot during wet periods                A or Ap horizon:
Flooding: None                                                Hue—10YR
Accelerated erosion: None or slight                           Value—2 or 3
Potential for frost action: High                              Chroma—1 or 2
100                                                                                                 Soil Survey of




Bw horizon:                                               Sawmill Series
   Hue—7.5YR or 10YR
   Value—4 or 5                                           Taxonomic classification: Fine-silty, mixed,
   Chroma—3 to 6                                             superactive, mesic Cumulic Endoaquolls
   Texture—loam or sandy loam
                                                            Typical Pedon (Official Series Description)
2BC and 2C horizons:
                                                          Sawmill silty clay loam, 0 to 2 percent slopes,
   Hue—7.5YR or 10YR
                                                          occasionally flooded; 300 feet south and 750 feet east
   Value—4 or 5
                                                          of the northwest corner of sec. 20, T. 15 N., R. 4 W.; in
   Chroma—4 to 6
                                                          Sangamon County, Illinois; USGS New City
   Texture—gravelly coarse sand, coarse sand,
                                                          topographic quadrangle; lat. 39 degrees 44 minutes 34
     loamy sand, or sand
                                                          seconds N. and long. 89 degrees 34 minutes 15
                                                          seconds W., NAD 27:
774A—Saude loam, 0 to 2 percent slopes                    Ap—0 to 10 inches; very dark gray (10YR 3/1) and
                                                              very dark grayish brown (10YR 3/2) silty clay
                        Setting
                                                              loam, gray (10YR 5/1) dry; weak fine subangular
Landform: Outwash plains                                      blocky structure; firm; few fine roots throughout;
                                                              few subrounded pebbles 1 to 3 millimeters in
                    Composition
                                                              diameter; slightly acid; clear smooth boundary.
Saude and similar soils: 100 percent                      A1—10 to 17 inches; black (10YR 2/1) and very dark
                                                              grayish brown (10YR 3/2) silty clay loam, dark
                Minor Components
                                                              gray (10YR 4/1) dry; moderate fine subangular
Similar soils:                                                blocky structure; firm; few fine roots between peds;
• Soils that have less gravel in the lower part               few subrounded pebbles 1 to 3 millimeters in
• Soils that do not have reddish colors                       diameter; few fine prominent yellowish brown
• Soils that have a thinner or lighter colored surface        (10YR 5/6) masses of iron in the matrix; few fine
layer                                                         concretions of manganese lining root channels
                                                              and pores; neutral; clear smooth boundary.
  Properties and Qualities of the Saude Soil              A2—17 to 25 inches; black (10YR 2/1) silty clay loam,
                                                              dark gray (10YR 4/1) dry; moderate fine and
Parent material: Outwash
                                                              medium angular blocky structure; firm; few fine
Drainage class: Well drained
                                                              roots between peds; few fine concretions of
Slowest permeability within a depth of 40 inches:
                                                              manganese lining root channels and pores; few
    Moderate
                                                              fine prominent yellowish brown (10YR 5/6)
Permeability below a depth of 60 inches: Very rapid
                                                              masses of iron in the matrix; neutral; clear smooth
Depth to restrictive feature: More than 80 inches
                                                              boundary.
Available water capacity to a depth of 60 inches: About
                                                          AB—25 to 32 inches; very dark gray (10YR 3/1) silty
    6.7 inches
                                                              clay loam, gray (10YR 5/1) dry; weak medium
Content of organic matter in the surface layer: 3 to 4
                                                              prismatic structure parting to moderate fine
    percent
                                                              subangular blocky; firm; few fine roots between
Shrink-swell potential: Low
                                                              peds; few fine concretions of manganese lining
Flooding: None
                                                              root channels and pores; few fine prominent
Accelerated erosion: None or slight
                                                              yellowish brown (10YR 5/6) masses of iron in the
Potential for frost action: Moderate
                                                              matrix; neutral; clear smooth boundary.
Hazard of corrosion: Low for steel and moderate for
                                                          Bg—32 to 40 inches; dark gray (10YR 4/1) silty clay
    concrete
                                                              loam; weak medium prismatic structure parting to
Surface runoff class: Low
                                                              moderate fine and medium angular blocky; firm;
Susceptibility to water erosion: Slight
                                                              few fine roots between peds; few faint very dark
Susceptibility to wind erosion: Slight
                                                              gray (10YR 3/1) organic coatings on faces of
                                                              peds; few fine concretions of manganese lining
                Interpretive Groups
                                                              root channels and pores; few fine prominent
Land capability classification: 2s                            strong brown (7.5YR 5/6) masses of iron in the
Prime farmland status: Prime farmland                         matrix; slightly alkaline; clear smooth boundary.
Hydric soil status: Not hydric                            Btg1—40 to 49 inches; grayish brown (10YR 5/2) silty
Rock Island County, Illinois                                                                                      101




    clay loam; moderate medium prismatic structure                           Minor Components
    parting to weak medium angular blocky; firm;
                                                             Similar soils:
    common distinct dark gray (10YR 4/1) clay films
                                                             • Soils that contain more clay in the subsoil
    on faces of peds; few fine concretions of
                                                             • Soils that contain less clay in the subsoil
    manganese lining root channels and pores; few
    fine prominent strong brown (7.5YR 5/6) and              Dissimilar soils:
    common fine distinct yellowish brown (10YR 5/4)          • The poorly drained Millington soils on toeslopes
    masses of iron in the matrix; slightly alkaline; clear
                                                                      Properties and Qualities of the
    smooth boundary.
                                                                               Sawmill Soil
Btg2—49 to 58 inches; grayish brown (2.5Y 5/2) silty
    clay loam; moderate medium prismatic structure;          Parent material: Alluvium
    firm; few distinct gray (10YR 5/1) clay films on         Drainage class: Poorly drained
    faces of peds; few fine concretions of manganese         Slowest permeability within a depth of 40 inches:
    lining pores; few fine prominent yellowish brown             Moderate
    (10YR 5/6) masses of iron in the matrix; slightly        Permeability below a depth of 60 inches: Moderate
    alkaline; gradual smooth boundary.                       Depth to restrictive feature: More than 80 inches
Cg—58 to 65 inches; grayish brown (2.5Y 5/2) silty           Available water capacity to a depth of 60 inches: About
    clay loam; massive; firm; very dark gray (10YR               12.5 inches
    3/1) channel linings and fillings; many medium           Content of organic matter in the surface layer: 4 to 5
    prominent yellowish brown (10YR 5/6) masses of               percent
    iron in the matrix; slightly alkaline.                   Shrink-swell potential: Moderate
                                                             Depth and months of the highest apparent seasonal
             Range in Characteristics
                                                                 high water table: At the surface, November to
Thickness of the mollic epipedon: 24 to 36 inches                June
Thickness of the solum: 36 to 60 inches                      Ponding depth: 0.2 foot during wet periods
                                                             Frequency and most likely period of flooding:
Ap or A horizon:
                                                                 Frequent, November to June
    Hue—10YR, 2.5Y, 5Y, or N
                                                             Potential for frost action: High
    Value—2 or 3
                                                             Hazard of corrosion: High for steel and low for
    Chroma—0 to 2
                                                                 concrete
    Texture—silty clay loam
                                                             Surface runoff class: Negligible
Bg or Btg horizon:                                           Susceptibility to water erosion: Slight
    Hue—10YR, 2.5Y, or 5Y                                    Susceptibility to wind erosion: Very slight
    Value—3 to 6
                                                                             Interpretive Groups
    Chroma—1 or 2
    Texture—silty clay loam; stratified in some pedons       Land capability classification: 5w
                                                             Prime farmland status: Not prime farmland
Cg horizon:
                                                             Hydric soil status: Hydric
    Hue—10YR, 2.5Y, 5Y, or N
    Value—4 to 6
    Chroma—0 to 2
    Texture—silty clay loam or clay loam; stratified in      3107A—Sawmill silty clay loam, 0 to 2
      some pedons                                               percent slopes, frequently flooded
                                                                                      Setting
1107A—Sawmill silty clay loam,                               Landform: Flood plains
   undrained, 0 to 2 percent slopes,
                                                                                 Composition
   frequently flooded
                                                             Sawmill and similar soils: 99 percent
                         Setting
                                                             Dissimilar soils: 1 percent
Landform: Flood plains
                                                                             Minor Components
                     Composition
                                                             Similar soils:
Sawmill and similar soils: 90 percent                        • Soils that contain more clay in the subsoil
Dissimilar soils: 10 percent                                 • Soils that contain less clay in the subsoil
102                                                                                                Soil Survey of




Dissimilar soils:                                         Dissimilar soils:
• Well drained soils on footslopes                        • Well drained soils on footslopes

 Properties and Qualities of the Sawmill Soil              Properties and Qualities of the Sawmill Soil
Parent material: Alluvium                                 Parent material: Alluvium
Drainage class: Poorly drained                            Drainage class: Poorly drained
Slowest permeability within a depth of 40 inches:         Slowest permeability within a depth of 40 inches:
    Moderate                                                  Moderate
Permeability below a depth of 60 inches: Moderate         Permeability below a depth of 60 inches: Moderate
Depth to restrictive feature: More than 80 inches         Depth to restrictive feature: More than 80 inches
Available water capacity to a depth of 60 inches: About   Available water capacity to a depth of 60 inches: About
    13 inches                                                 11.2 inches
Content of organic matter in the surface layer: 4 to 5    Content of organic matter in the surface layer: 4 to 5
    percent                                                   percent
Shrink-swell potential: Moderate                          Shrink-swell potential: Moderate
Depth and months of the highest apparent seasonal         Depth and months of the highest apparent seasonal
    high water table: At the surface, January to              high water table: At the surface, January to May
    May                                                   Ponding depth: 0.2 foot during wet periods
Frequency and most likely period of flooding:             Frequency and most likely period of flooding: Rare,
    Frequent, November to June                                November to June
Potential for frost action: High                          Potential for frost action: High
Hazard of corrosion: High for steel and low for           Hazard of corrosion: High for steel and low for
    concrete                                                  concrete
Surface runoff class: Negligible                          Surface runoff class: Low
Susceptibility to water erosion: Slight                   Susceptibility to water erosion: Slight
Susceptibility to wind erosion: Very slight               Susceptibility to wind erosion: Very slight

                Interpretive Groups                                       Interpretive Groups
Land capability classification: 3w                        Land capability classification: 2w
Prime farmland status: Prime farmland where               Prime farmland status: Prime farmland where drained
    drained and either protected from flooding or         Hydric soil status: Hydric
    not frequently flooded during the growing
    season
Hydric soil status: Hydric                                8107+—Sawmill silt loam, 0 to 2 percent
                                                             slopes, occasionally flooded,
                                                             overwash
7107A—Sawmill silty clay loam, 0 to 2                                              Setting
   percent slopes, rarely flooded
                                                          Landform: Flood plains
                         Setting
                                                                              Composition
Landform: Flood plains
                                                          Sawmill and similar soils: 85 percent
                                                          Dissimilar soils: 15 percent
                    Composition
                                                                          Minor Components
Sawmill and similar soils: 90 percent
Dissimilar soils: 10 percent                              Similar soils:
                                                          • Soils that have less clay in the middle and lower
                Minor Components                          parts of the control section
                                                          • Soils that are calcareous in the control section
Similar soils:
• Soils that contain more clay in the subsoil             Dissimilar soils:
• Soils that contain less clay in the subsoil             • Well drained soils on summits
Rock Island County, Illinois                                                                                   103




 Properties and Qualities of the Sawmill Soil              Bt1—15 to 21 inches; yellowish brown (10YR 5/4) silt
                                                              loam; moderate fine and medium subangular
Parent material: Alluvium
                                                              blocky structure; friable; few faint dark brown
Drainage class: Poorly drained
                                                              (10YR 3/3) clay films and few faint light yellowish
Slowest permeability within a depth of 40 inches:
                                                              brown (10YR 6/4) silt coatings on faces of peds;
    Moderate
                                                              moderately acid; clear smooth boundary.
Permeability below a depth of 60 inches: Moderate
                                                           Bt2—21 to 27 inches; brown (7.5YR 5/4) silt loam;
Depth to restrictive feature: More than 80 inches
                                                              moderate fine and medium subangular blocky
Available water capacity to a depth of 60 inches: About
                                                              structure; firm; few faint dark brown (10YR 3/3)
    12.8 inches
                                                              clay films and few faint light yellowish brown
Content of organic matter in the surface layer: 4 to 5
                                                              (10YR 6/4) silt coatings on faces of peds; strongly
    percent
                                                              acid; clear smooth boundary.
Shrink-swell potential: Moderate
                                                           Bt3—27 to 34 inches; yellowish brown (10YR 5/4) silt
Depth and months of the highest apparent seasonal
                                                              loam; moderate medium angular blocky structure;
    high water table: At the surface, January to May
                                                              firm; common faint dark brown (10YR 3/3) clay
Frequency and most likely period of flooding:
                                                              films on faces of peds; strongly acid; gradual
    Occasional, November to June
                                                              smooth boundary.
Potential for frost action: High
                                                           Bt4—34 to 44 inches; brown (10YR 5/3) silt loam;
Hazard of corrosion: High for steel and low for
                                                              weak medium and coarse prismatic structure; firm;
    concrete
                                                              few faint dark brown (10YR 3/3) clay films and few
Surface runoff class: Negligible
                                                              faint light yellowish brown (10YR 6/4) silt coatings
Susceptibility to water erosion: Slight
                                                              on faces of peds; moderately acid; gradual smooth
Susceptibility to wind erosion: Slight
                                                              boundary.
                Interpretive Groups                        BC—44 to 70 inches; brown (10YR 4/3) silt loam;
                                                              weak very coarse prismatic structure; friable; few
Land capability classification: 2w
                                                              faint dark brown (7.5YR 4/2) clay films on vertical
Prime farmland status: Prime farmland where drained
                                                              faces of peds; moderately acid; gradual smooth
Hydric soil status: Hydric
                                                              boundary.
                                                           C—70 to 95 inches; light brownish gray (10YR 6/2)
Seaton Series                                                 and brown (10YR 5/3) silt loam; massive; friable;
                                                              common fine faint dark yellowish brown (10YR
Taxonomic classification: Fine-silty, mixed,                  4/4) and yellowish brown (10YR 5/6) masses of
   superactive, mesic Typic Hapludalfs                        iron; massive; friable; slightly acid.
                   Typical Pedon                                       Range in Characteristics
Seaton silt loam, 2 to 5 percent slopes; 660 feet north    Thickness of the loess: More than 80 inches
and 30 feet east of the center of sec. 8, T. 11 N., R. 4   Thickness of the solum: 42 to more than 60 inches
W.; in Whiteside County, Illinois; USGS Rozetta
                                                           Ap or A horizon:
topographic quadrangle; lat. 40 degrees 57 minutes 44
                                                               Hue—10YR
seconds N. and long. 90 degrees 52 minutes 24
                                                               Value—2 to 4
seconds W., NAD 27:
                                                               Chroma—2 or 3
A—0 to 4 inches; dark brown (10YR 3/3) silt loam,              Texture—silt loam or silt
  brown (10YR 5/3) dry; weak fine granular                     Reaction—moderately acid to neutral
  structure; very friable; slightly acid; clear smooth
                                                           E horizon (if it occurs):
  boundary.
                                                               Hue—10YR
E—4 to 9 inches; brown (10YR 4/3) silt loam, pale
                                                               Value—4 to 6
  brown (10YR 6/3) dry; weak thin platy structure;
                                                               Chroma—2 to 4
  friable; slightly acid; clear smooth boundary.
                                                               Texture—silt loam or silt
BE—9 to 15 inches; yellowish brown (10YR 5/4) silt
                                                               Reaction—moderately acid to neutral
  loam; weak fine and medium subangular blocky
  structure; friable; few faint dark brown (10YR 3/3)      Bt horizon:
  clay films and common faint light yellowish brown            Hue—7.5YR, 10YR, or 2.5Y
  (10YR 6/4) silt coatings on faces of peds;                   Value—4 or 5
  moderately acid; clear smooth boundary.                      Chroma—3 to 6
104                                                                                                   Soil Survey of




      Texture—silt loam or silt                           Susceptibility to water erosion: Moderate
      Reaction—very strongly acid to neutral              Susceptibility to wind erosion: Slight
BC horizon (if it occurs):                                                Interpretive Groups
   Hue—10YR or 2.5Y
                                                          Land capability classification: 2e
   Value—4 or 5
                                                          Prime farmland status: Prime farmland
   Chroma—3 or 4
                                                          Hydric soil status: Not hydric
C horizon:
   Hue—10YR or 2.5Y
   Value—4 to 6                                           274B2—Seaton silt loam, 2 to 5 percent
   Chroma—2 to 6                                             slopes, eroded
   Texture—silt loam or silt
                                                                                 Setting
   Reaction—moderately acid to moderately alkaline
                                                          Landform: Ground moraines
                                                                              Composition
274B—Seaton silt loam, 2 to 5 percent
   slopes                                                 Seaton and similar soils: 97 percent
                                                          Dissimilar soils: 3 percent
                        Setting
                                                                          Minor Components
Landform: Ground moraines
Position on the landform: Shoulders                       Similar soils:
                                                          • Soils that have a darker surface layer
                     Composition
                                                          • Soils that have a seasonal high water table within a
Seaton and similar soils: 92 percent                      depth of 60 inches
Dissimilar soils: 8 percent
                                                          Dissimilar soils:
                 Minor Components                         • The excessively drained Oakville soils on
                                                          backslopes
Similar soils:
• Soils that have a darker surface layer                    Properties and Qualities of the Seaton Soil
• Soils that have a seasonal high water table within a
                                                          Parent material: Loess
depth of 60 inches
                                                          Drainage class: Well drained
Dissimilar soils:                                         Slowest permeability within a depth of 40 inches:
• The somewhat poorly drained Joy soils on summits            Moderate
• The excessively drained Oakville soils on shoulders     Permeability below a depth of 60 inches: Moderate
• The well drained Thebes soils on shoulders              Depth to restrictive feature: More than 80 inches
                                                          Available water capacity to a depth of 60 inches: About
  Properties and Qualities of the Seaton Soil
                                                              12.7 inches
Parent material: Loess                                    Content of organic matter in the surface layer: 1 to 3
Drainage class: Well drained                                  percent
Slowest permeability within a depth of 40 inches:         Shrink-swell potential: Low
    Moderate                                              Flooding: None
Permeability below a depth of 60 inches: Moderate         Accelerated erosion: The surface layer has been
Depth to restrictive feature: More than 80 inches             thinned by erosion.
Available water capacity to a depth of 60 inches: About   Potential for frost action: High
    12.7 inches                                           Hazard of corrosion: Low for steel and moderate for
Content of organic matter in the surface layer: 1 to 3        concrete
    percent                                               Surface runoff class: Low
Shrink-swell potential: Low                               Susceptibility to water erosion: Moderate
Flooding: None                                            Susceptibility to wind erosion: Slight
Accelerated erosion: None or slight
                                                                          Interpretive Groups
Potential for frost action: High
Hazard of corrosion: Low for steel and moderate for       Land capability classification: 2e
    concrete                                              Prime farmland status: Prime farmland
Surface runoff class: Low                                 Hydric soil status: Not hydric
Rock Island County, Illinois                                                                                 105




274C2—Seaton silt loam, 5 to 10 percent                                       Composition
   slopes, eroded                                         Seaton and similar soils: 98 percent
                                                          Dissimilar soils: 2 percent
                        Setting
                                                                          Minor Components
Landform: Ground moraines
Position on the landform: Shoulders                       Similar soils:
                                                          • Soils that have a darker surface layer
                    Composition
                                                          • Soils that are more eroded
Seaton and similar soils: 97 percent
                                                          Dissimilar soils:
Dissimilar soils: 3 percent
                                                          • The excessively drained Oakville soils on
                Minor Components                          backslopes
Similar soils:
                                                            Properties and Qualities of the Seaton Soil
• Soils that have a darker surface layer
• Soils that are more eroded                              Parent material: Loess
                                                          Drainage class: Well drained
Dissimilar soils:
                                                          Slowest permeability within a depth of 40 inches:
• The excessively drained Oakville soils on backslopes
                                                              Moderate
• The well drained Tell and Thebes soils on
                                                          Permeability below a depth of 60 inches: Moderate
backslopes and shoulders
                                                          Depth to restrictive feature: More than 80 inches
  Properties and Qualities of the Seaton Soil             Available water capacity to a depth of 60 inches: About
                                                              12.7 inches
Parent material: Loess
                                                          Content of organic matter in the surface layer: 0.5 to
Drainage class: Well drained
                                                              2.0 percent
Slowest permeability within a depth of 40 inches:
                                                          Shrink-swell potential: Low
    Moderate
                                                          Flooding: None
Permeability below a depth of 60 inches: Moderate
                                                          Accelerated erosion: The surface layer has been
Depth to restrictive feature: More than 80 inches
                                                              thinned by erosion.
Available water capacity to a depth of 60 inches: About
                                                          Potential for frost action: High
    12.7 inches
                                                          Hazard of corrosion: Low for steel and moderate for
Content of organic matter in the surface layer: 0.5 to
                                                              concrete
    2.0 percent
                                                          Surface runoff class: Medium
Shrink-swell potential: Low
                                                          Susceptibility to water erosion: High
Flooding: None
                                                          Susceptibility to wind erosion: Slight
Accelerated erosion: The surface layer has been
    thinned by erosion.                                                   Interpretive Groups
Potential for frost action: High
                                                          Land capability classification: 4e
Hazard of corrosion: Low for steel and moderate for
                                                          Prime farmland status: Not prime farmland
    concrete
                                                          Hydric soil status: Not hydric
Surface runoff class: Medium
Susceptibility to water erosion: High
Susceptibility to wind erosion: Slight
                                                          943D2—Seaton-Timula silt loams, 10 to 18
                Interpretive Groups                          percent slopes, eroded
Land capability classification: 3e
                                                                                 Setting
Prime farmland status: Not prime farmland
Hydric soil status: Not hydric                            Landform: Loess hills
                                                          Position on the landform: Seaton—upper and middle
                                                              parts of backslopes; Timula—nose slopes and the
274D2—Seaton silt loam, 10 to 18 percent                      middle and lower parts of backslopes
   slopes, eroded
                                                                              Composition
                        Setting
                                                          Seaton and similar soils: 60 percent
Landform: Ground moraines                                 Timula and similar soils: 30 percent
Position on the landform: Backslopes                      Dissimilar soils: 10 percent
106                                                                                                  Soil Survey of




                Minor Components                                          Interpretive Groups
Similar soils:                                            Land capability classification: Seaton—3e; Timula—3e
• Soils that have a darker surface layer                  Prime farmland status: Not prime farmland
• Soils that are calcareous throughout                    Hydric soil status: Seaton—not hydric; Timula—not
                                                              hydric
Dissimilar soils:
• The somewhat poorly drained Joy soils on summits
• The excessively drained Oakville soils on               943F2—Seaton-Timula silt loams, 18 to 35
backslopes                                                   percent slopes, eroded
  Properties and Qualities of the Seaton Soil
                                                                                 Setting
Parent material: Loess
                                                          Landform: Ground moraines
Drainage class: Well drained
                                                          Position on the landform: Seaton—upper and middle
Slowest permeability within a depth of 40 inches:
                                                              parts of backslopes; Timula—nose slopes and the
    Moderate
                                                              middle and lower parts of backslopes
Permeability below a depth of 60 inches: Moderate
Depth to restrictive feature: More than 80 inches                             Composition
Available water capacity to a depth of 60 inches: About
                                                          Seaton and similar soils: 45 percent
    12.6 inches
                                                          Timula and similar soils: 40 percent
Content of organic matter in the surface layer: 0.5 to
                                                          Dissimilar soils: 15 percent
    2.0 percent
Shrink-swell potential: Low                                               Minor Components
Flooding: None
                                                          Similar soils:
Accelerated erosion: The surface layer has been
                                                          • Soils that have a darker surface layer
    thinned by erosion.
                                                          • Soils that are calcareous throughout
Potential for frost action: High
Hazard of corrosion: Low for steel and moderate for       Dissimilar soils:
    concrete                                              • The somewhat poorly drained Joy soils on summits
Surface runoff class: Medium                              • The well drained Marseilles soils on backslopes
Susceptibility to water erosion: High                     • The excessively drained Oakville soils on
Susceptibility to wind erosion: Slight                    backslopes
  Properties and Qualities of the Timula Soil               Properties and Qualities of the Seaton Soil
Parent material: Loess                                    Parent material: Loess
Drainage class: Well drained                              Drainage class: Well drained
Slowest permeability within a depth of 40 inches:         Slowest permeability within a depth of 40 inches:
    Moderate                                                  Moderate
Permeability below a depth of 60 inches: Moderate         Permeability below a depth of 60 inches: Moderate
Depth to restrictive feature: More than 80 inches         Depth to restrictive feature: More than 80 inches
Available water capacity to a depth of 60 inches: About   Available water capacity to a depth of 60 inches: About
    12.1 inches                                               12.7 inches
Content of organic matter in the surface layer: 1 to 2    Content of organic matter in the surface layer: 0.5 to
    percent                                                   2.0 percent
Shrink-swell potential: Low                               Shrink-swell potential: Low
Flooding: None                                            Flooding: None
Accelerated erosion: The surface layer has been           Accelerated erosion: The surface layer has been
    thinned by erosion.                                       thinned by erosion.
Potential for frost action: High                          Potential for frost action: High
Hazard of corrosion: Low for steel and low for            Hazard of corrosion: Low for steel and moderate for
    concrete                                                  concrete
Surface runoff class: Medium                              Surface runoff class: High
Susceptibility to water erosion: High                     Susceptibility to water erosion: High
Susceptibility to wind erosion: Slight                    Susceptibility to wind erosion: Slight
Rock Island County, Illinois                                                                                  107




  Properties and Qualities of the Timula Soil                throughout; few distinct very dark grayish brown
                                                             (10YR 3/2) organic coatings and few faint dark
Parent material: Loess
                                                             brown (10YR 3/3) clay bridges on sand grains;
Drainage class: Well drained
                                                             strongly acid; clear smooth boundary.
Slowest permeability within a depth of 40 inches:
                                                          Bw2—24 to 31 inches; brown (7.5YR 5/4) sand; weak
    Moderate
                                                             medium and coarse subangular blocky structure;
Permeability below a depth of 60 inches: Moderate
                                                             very friable; few fine roots throughout; moderately
Depth to restrictive feature: More than 80 inches
                                                             acid; clear smooth boundary.
Available water capacity to a depth of 60 inches: About
                                                          C—31 to 60 inches; reddish yellow (7.5YR 6/6) sand;
    12.2 inches
                                                             single grain; loose; moderately acid.
Content of organic matter in the surface layer: 1 to 2
    percent
                                                                       Range in Characteristics
Shrink-swell potential: Low
Flooding: None                                            Thickness of the mollic epipedon: 10 to 24 inches
Accelerated erosion: The surface layer has been
                                                          Ap or A horizon:
    thinned by erosion.
                                                              Hue—7.5YR or 10YR
Potential for frost action: High
                                                              Value—2 or 3
Hazard of corrosion: Low for steel and low for concrete
                                                              Chroma—1 or 2
Surface runoff class: High
                                                              Texture—fine sand, sand, loamy fine sand, or
Susceptibility to water erosion: High
                                                                 loamy sand
Susceptibility to wind erosion: Slight
                                                          Bw horizon:
                Interpretive Groups
                                                             Hue—7.5YR or 10YR
Land capability classification: Seaton—6e; Timula—6e         Value—3 to 6
Prime farmland status: Not prime farmland                    Chroma—3 to 6
Hydric soil status: Seaton—not hydric; Timula—not            Texture—fine sand, sand, loamy sand, or loamy
    hydric                                                      fine sand
                                                          C horizon:
Sparta Series                                                Hue—7.5YR or 10YR
                                                             Value—4 to 6
Taxonomic classification: Sandy, mixed, mesic Entic          Chroma—3 to 6
   Hapludolls                                                Texture—fine sand or sand
                   Typical Pedon
Sparta loamy sand, 0 to 2 percent slopes; 2,150 feet      88A—Sparta loamy sand, 0 to 2 percent
north and 1,939 feet east of the southwest corner of         slopes
sec. 20, T. 23 N., R. 10 E.; in Ogle County, Illinois;
                                                                                  Setting
USGS Daysville topographic quadrangle; lat. 41
degrees 57 minutes 58 seconds N. and long. 89             Landform: Stream terraces and outwash plains
degrees 22 minutes 13 seconds W., NAD 27:                 Position on the landform: Summits
A1—0 to 10 inches; very dark gray (10YR 3/1) loamy                            Composition
   sand, grayish brown (10YR 5/2) dry; weak medium
                                                          Sparta and similar soils: 91 percent
   subangular blocky structure parting to moderate
                                                          Dissimilar soils: 9 percent
   very fine granular; very friable; many fine roots
   throughout; neutral; clear smooth boundary.                            Minor Components
A2—10 to 17 inches; very dark grayish brown (10YR
                                                          Similar soils:
   3/2) loamy sand, grayish brown (10YR 5/2) dry;
                                                          • Soils that have a lighter colored surface layer
   very weak medium and coarse subangular blocky
                                                          • Soils that have more gravel
   structure parting to moderate very fine granular;
                                                          • Soils that have more clay in the upper part
   very friable; common fine roots throughout;
   neutral; clear smooth boundary.                        Dissimilar soils:
Bw1—17 to 24 inches; dark yellowish brown (10YR           • The well drained Coyne soils on summits
   4/4) sand; weak medium and coarse subangular           • Poorly drained soils in depressions
   blocky structure; very friable; few fine roots         • Somewhat poorly drained soils on footslopes
108                                                                                                  Soil Survey of




  Properties and Qualities of the Sparta Soil                           Range in Characteristics
Parent material: Sandy outwash                             Depth to the base of the argillic horizon: 16 to 24
Drainage class: Excessively drained                           inches
Slowest permeability within a depth of 40 inches:          Depth to carbonates: 14 to 24 inches
    Moderately rapid
                                                           Ap or A horizon:
Permeability below a depth of 60 inches: Rapid
                                                               Hue—10YR
Depth to restrictive feature: More than 80 inches
                                                               Value—3 to 5
Available water capacity to a depth of 60 inches: About
                                                               Chroma—2 to 4
    5 inches
                                                               Texture—loam or silt loam
Content of organic matter in the surface layer: 1 to 2
    percent                                                E and/or BE horizon (if it occurs):
Shrink-swell potential: Low                                    Hue—10YR
Flooding: None                                                 Value—3 to 5
Accelerated erosion: None or slight                            Chroma—2 to 4
Potential for frost action: Low                                Texture—silt loam or loam
Hazard of corrosion: Low for steel and moderate for
                                                           Bt and/or BC horizon:
    concrete
                                                               Hue—7.5YR or 10YR
Surface runoff class: Very low
                                                               Value—4 or 5
Susceptibility to water erosion: Slight
                                                               Chroma—3 or 4
Susceptibility to wind erosion: High
                                                               Texture—clay loam, silty clay loam, or loam
                Interpretive Groups
                                                           C horizon:
Land capability classification: 4s                            Hue—7.5YR, 10YR, or 2.5Y
Prime farmland status: Not prime farmland                     Value—5 or 6
Hydric soil status: Not hydric                                Chroma—2 to 6
                                                              Texture—loam, clay loam, silt loam, or fine sandy
                                                                  loam
Strawn Series
Taxonomic classification: Fine-loamy, mixed, active,       959G—Strawn-Chute complex, 18 to 60
   mesic Typic Hapludalfs                                     percent slopes
                   Typical Pedon
                                                                                   Setting
Strawn loam, 18 to 60 percent slopes; 1,627 feet south
                                                           Landform: Ground moraines
and 2,225 feet east of the northwest corner of sec. 31,
                                                           Position on the landform: Strawn—lower and middle
T. 16 N., R. 5 W.; in Rock Island County, Illinois; USGS
                                                               parts of backslopes; Chute—middle and upper
Blanchard Island topographic quadrangle; lat. 41
                                                               parts of backslopes
degrees 20 minutes 34 seconds N. and long. 90
degrees 00 minutes 27 seconds W., NAD 27:                                      Composition
A1—0 to 6 inches; very dark grayish brown (10YR 3/2)       Strawn and similar soils: 60 percent
   loam; strong very fine and fine granular structure;     Chute and similar soils: 40 percent
   friable; slightly acid; clear smooth boundary.
                                                                           Minor Components
A2—6 to 12 inches; brown (10YR 4/3) and very dark
   grayish brown (10YR 3/2) loam; moderate fine and        Similar soils:
   medium subangular blocky structure; friable;            • Soils that are not calcareous
   moderately acid; clear smooth boundary.                 • Soils that have slopes of less than 18 percent
Bt—12 to 23 inches; dark yellowish brown (10YR 4/4)
                                                             Properties and Qualities of the Strawn Soil
   clay loam; weak medium and coarse subangular
   blocky structure; friable; discontinuous dark brown     Parent material: Till
   (10YR 3/3) clay films on faces of peds; neutral;        Drainage class: Well drained
   gradual smooth boundary.                                Slowest permeability within a depth of 40 inches:
C—23 to 60 inches; yellowish brown (10YR 5/4) loam;            Moderate
   massive; violently effervescent; moderately             Permeability below a depth of 60 inches: Moderate
   alkaline.                                               Depth to restrictive feature: More than 80 inches
Rock Island County, Illinois                                                                                  109




Available water capacity to a depth of 60 inches: About      loam, light brownish gray (10YR 6/2) dry;
    7.3 inches                                               moderate fine granular structure; very friable; few
Content of organic matter in the surface layer: 1 to 3       fine roots; common fine black (5YR 2/1)
    percent                                                  accumulations of iron and manganese; neutral;
Shrink-swell potential: Moderate                             abrupt smooth boundary.
Flooding: None                                            E—8 to 13 inches; brown (10YR 5/3) silt loam;
Accelerated erosion: None or slight                          moderate thin and very thin platy structure; friable;
Potential for frost action: Moderate                         few fine roots; common fine faint light brownish
Hazard of corrosion: Moderate for steel and moderate         gray (10YR 6/2) and common fine distinct
    for concrete                                             yellowish brown (10YR 5/6 and 5/8) redoximorphic
Surface runoff class: High                                   features; common fine black (5YR 2.5/1)
Susceptibility to water erosion: High                        accumulations of iron and manganese; strongly
Susceptibility to wind erosion: Slight                       acid; clear smooth boundary.
                                                          Bt1—13 to 24 inches; yellowish brown (10YR 5/4) silty
  Properties and Qualities of the Chute Soil
                                                             clay loam; moderate medium subangular blocky
Parent material: Eolian sands                                structure; friable; few fine roots; many distinct
Drainage class: Excessively drained                          grayish brown (10YR 5/2) clay films and many
Slowest permeability within a depth of 40 inches:            distinct light gray (10YR 7/2) silt coatings on faces
    Rapid                                                    of peds; common fine distinct light brownish gray
Permeability below a depth of 60 inches: Very rapid          (10YR 6/2), yellowish brown (10YR 5/8), and
Depth to restrictive feature: More than 80 inches            strong brown (7.5YR 5/6) redoximorphic features;
Available water capacity to a depth of 60 inches: About      common fine black (10YR 2/1) accumulations of
    4.1 inches                                               iron and manganese; strongly acid; clear smooth
Content of organic matter in the surface layer: 0.5 to       boundary.
    2.0 percent                                           Bt2—24 to 30 inches; yellowish brown (10YR 5/4) silty
Shrink-swell potential: Low                                  clay loam; moderate medium prismatic structure
Flooding: None                                               parting to moderate medium subangular blocky;
Accelerated erosion: None or slight                          firm; few fine roots; many distinct grayish brown
Potential for frost action: Low                              (10YR 5/2) clay films on faces of peds; common
Hazard of corrosion: Low for steel and low for concrete      fine distinct light brownish gray (10YR 6/2),
Surface runoff class: Low                                    yellowish brown (10YR 5/8), and strong brown
Susceptibility to water erosion: Slight                      (7.5YR 5/6) redoximorphic features; common fine
Susceptibility to wind erosion: Very high                    black (10YR 2/1) accumulations of iron and
                                                             manganese; strongly acid; clear smooth boundary.
                Interpretive Groups
                                                          Bt3—30 to 38 inches; yellowish brown (10YR 5/4) silty
Land capability classification: Strawn—7e; Chute—7s          clay loam; moderate medium prismatic structure;
Prime farmland status: Not prime farmland                    friable; few fine roots; common distinct grayish
Hydric soil status: Strawn—not hydric; Chute—not             brown (10YR 5/2) clay films on faces of peds;
    hydric                                                   common fine distinct yellowish brown (10YR 5/8),
                                                             strong brown (7.5YR 5/6), and light brownish gray
                                                             (2.5YR 6/2) redoximorphic features; common fine
Stronghurst Series                                           black (10YR 2/1) accumulations of iron and
                                                             manganese; strongly acid; clear smooth boundary.
Taxonomic classification: Fine-silty, mixed,
                                                          Bt4—38 to 47 inches; yellowish brown (10YR 5/4) silty
   superactive, mesic Aeric Endoaqualfs
                                                             clay loam; moderate coarse prismatic structure;
                   Typical Pedon                             friable; few fine roots; few distinct grayish brown
                                                             (10YR 5/2) clay films on faces of peds; common
Stronghurst silt loam, 0 to 2 percent slopes; 582 feet
                                                             fine distinct light brownish gray (10YR 6/2 and
south and 78 feet west of the northeast corner of sec.
                                                             2.5Y 6/2) and yellowish brown (10YR 5/8)
23, T. 16 N., R. 8 E.; in Bureau County, Illinois; USGS
                                                             redoximorphic features; common fine black (10YR
Wyanet topographic quadrangle; lat. 41 degrees 16
                                                             2/1) accumulations of iron and manganese;
minutes 32 seconds N. and long. 89 degrees 31
                                                             strongly acid; gradual smooth boundary.
minutes 47 seconds W., NAD 27:
                                                          C—47 to 60 inches; yellowish brown (10YR 5/4) silt
Ap—0 to 8 inches; dark grayish brown (10YR 4/2) silt         loam; massive; friable; common fine distinct strong
110                                                                                                  Soil Survey of




      brown (7.5YR 5/6) and light brownish gray (2.5Y               Properties and Qualities of the
      6/2) redoximorphic features; common fine black                      Stronghurst Soil
      (10YR 2/1) accumulations of iron and manganese;
                                                           Parent material: Loess
      moderately acid.
                                                           Drainage class: Somewhat poorly drained
             Range in Characteristics                      Slowest permeability within a depth of 40 inches:
                                                               Moderate
Thickness of the solum: More than 42 inches
                                                           Permeability below a depth of 60 inches: Moderate
Depth to the top of the argillic horizon: 6 to 24 inches
                                                           Depth to restrictive feature: More than 80 inches
Ap or A horizon:                                           Available water capacity to a depth of 60 inches: About
    Value—3 to 6                                               11.9 inches
    Chroma—1 or 2                                          Content of organic matter in the surface layer: 1 to 3
                                                               percent
E horizon:
                                                           Shrink-swell potential: Moderate
    Value—4 to 6
                                                           Depth and months of the highest apparent seasonal
    Chroma—2 or 3
                                                               high water table: 0.5 foot, January to May
Bt or Btg horizon:                                         Flooding: None
    Hue—10YR or 2.5Y                                       Accelerated erosion: None or slight
    Value—4 to 6                                           Potential for frost action: High
    Chroma—1 to 4                                          Hazard of corrosion: High for steel and moderate for
    Texture—silty clay loam or silt loam                       concrete
                                                           Surface runoff class: Low
C or Cg horizon:
                                                           Susceptibility to water erosion: Slight
    Hue—10YR or 2.5Y
                                                           Susceptibility to wind erosion: Slight
    Value—4 to 6
    Chroma—1 to 4                                                          Interpretive Groups
    Texture—silt loam or silty clay loam
                                                           Land capability classification: 2w
                                                           Prime farmland status: Prime farmland where drained
278A—Stronghurst silt loam, 0 to 2                         Hydric soil status: Not hydric
   percent slopes
                        Setting                            Sylvan Series
Landform: Ground moraines                                  Taxonomic classification: Fine-silty, mixed,
Position on the landform: Summits                             superactive, mesic Typic Hapludalfs
                    Composition                                               Typical Pedon
Stronghurst and similar soils: 97 percent                  Sylvan silt loam, 10 to 18 percent slopes; 140 feet east
Dissimilar soils: 3 percent                                and 100 feet south of the center of sec. 34, T. 17 N., R.
                                                           8 E.; in Bureau County, Illinois; USGS Buda Northeast
                 Minor Components
                                                           topographic quadrangle; lat. 41 degrees 25 minutes 55
Similar soils:                                             seconds N. and long. 89 degrees 33 minutes 34
• Soils that have a darker surface layer                   seconds W., NAD 27:
• Soils that have an average of more than 35 percent
                                                           A—0 to 5 inches; very dark grayish brown (10YR 3/2)
clay in the subsoil
                                                             silt loam, grayish brown (10YR 5/2) dry; moderate
• Soils that have a seasonal high water table within a
                                                             medium and fine granular structure; friable; many
depth of 1 foot
                                                             very fine and fine roots; neutral; clear smooth
• Soils that are eroded; on slopes of 2 to 5 percent
                                                             boundary.
near the head of drainageways
                                                           E—5 to 10 inches; mixed dark grayish brown (10YR
Dissimilar soils:                                            4/2) and brown (10YR 4/3) silt loam, pale brown
• The well drained Fayette and Greenbush soils on            (10YR 6/3) dry; weak medium platy structure
shoulders                                                    parting to moderate medium granular; friable;
• The well drained Rozetta soils on summits                  many very fine roots; few distinct very dark grayish
Rock Island County, Illinois                                                                                      111




   brown (10YR 3/2) organic coatings and light                coarse light-colored concretions of calcium
   brownish gray (10YR 6/2) silt coatings on faces of         carbonate; strongly effervescent; slightly alkaline;
   peds; slightly acid; clear smooth boundary.                gradual wavy boundary.
Bt1—10 to 15 inches; brown (10YR 4/3) silty clay           C2—54 to 60 inches; brownish yellow (10YR 6/6) silt
   loam; moderate fine and very fine subangular               loam; few medium prominent light brownish gray
   blocky structure; friable; common very fine roots;         (10YR 6/2) mottles; massive; friable; few fine dark
   few distinct dark brown (10YR 3/3) clay films and          accumulations of iron and manganese; violently
   very few distinct light brownish gray (10YR 6/2) silt      effervescent; moderately alkaline.
   coatings on faces of peds; few fine dark
                                                                        Range in Characteristics
   accumulations of iron and manganese; neutral;
   clear smooth boundary.                                  Depth to carbonates: 22 to 40 inches
Bt2—15 to 21 inches; dark yellowish brown (10YR 4/4)       Thickness of the solum: 22 to 40 inches
   silty clay loam; moderate medium and fine
                                                           Ap or A horizon:
   subangular blocky structure; friable; common very
                                                               Value—4 to 6
   fine roots; common distinct brown (7.5YR 4/4) clay
                                                               Chroma—2 to 4
   films on faces of peds; few fine dark
                                                               Texture—silt loam
   accumulations of iron and manganese; slightly
   acid; clear smooth boundary.                            E horizon:
Bt3—21 to 27 inches; yellowish brown (10YR 5/4) silty          Hue—10YR
   clay loam; weak medium prismatic structure                  Value—4 or 5
   parting to moderate medium subangular blocky;               Chroma—2 to 4
   friable; common very fine roots; few distinct dark
                                                           Bt horizon:
   yellowish brown (10YR 4/4) clay films and very
                                                               Hue—7.5YR or 10YR
   few distinct light brownish gray (10YR 6/2) silt
                                                               Value—4 or 5
   coatings on faces of peds; slightly effervescent;
                                                               Chroma—3 to 6
   few fine dark accumulations of iron and
                                                               Texture—silty clay loam or silt loam
   manganese; neutral; clear smooth boundary.
Bt4—27 to 35 inches; yellowish brown (10YR 5/4) silt       C and/or Cg horizon:
   loam; common fine distinct yellowish brown (10YR           Hue—10YR or 2.5Y
   5/6) and few fine distinct light brownish gray             Value—4 to 6
   (10YR 6/2) relict mottles; weak medium prismatic           Chroma—2 to 4
   structure parting to moderate medium subangular            Texture—silt loam or silt
   blocky; friable; common very fine roots; few
   prominent light gray (10YR 7/2) silt coatings and
   common faint brown (7.5YR 4/4) clay films on            19C3—Sylvan silty clay loam, 5 to 10
   faces of peds; few fine dark accumulations of iron         percent slopes, severely eroded
   and manganese; neutral; clear smooth boundary.
                                                                                    Setting
BC—35 to 40 inches; yellowish brown (10YR 5/4) silt
   loam; common medium distinct light brownish gray        Landform: Ground moraines
   (10YR 6/2) mottles; weak coarse prismatic               Position on the landform: Backslopes and shoulders
   structure parting to weak coarse subangular
                                                                                Composition
   blocky; friable; few very fine roots; few faint dark
   yellowish brown (10YR 4/4) clay films on faces of       Sylvan and similar soils: 92 percent
   peds; few fine dark accumulations of iron and           Dissimilar soils: 8 percent
   manganese; few medium light-colored concretions
                                                                            Minor Components
   of calcium carbonate; slightly effervescent; slightly
   alkaline; gradual wavy boundary.                        Similar soils:
C1—40 to 54 inches; light yellowish brown (2.5Y 6/4)       • Soils that are not calcareous within a depth of 40
   silt loam; common medium distinct light brownish        inches
   gray (10YR 6/2) and few fine distinct brownish          • Soils that are underlain by glacial till within a depth
   yellow (10YR 6/6) mottles; appears massive but          of 60 inches
   has planes of weakness; friable; few fine dark          • Soils having subsurface horizons that are
   accumulations of iron and manganese; common             calcareous within a depth of 20 inches
112                                                                                                     Soil Survey of




Dissimilar soils:                                           Dissimilar soils:
• The somewhat poorly drained Atlas soils on                • The somewhat poorly drained Atlas soils on
backslopes                                                  backslopes
• The well drained Thebes soils on shoulders and            • The well drained Thebes soils on shoulders and
backslopes                                                  backslopes
  Properties and Qualities of the Sylvan Soil                 Properties and Qualities of the Sylvan Soil
Parent material: Loess                                      Parent material: Loess
Drainage class: Well drained                                Drainage class: Well drained
Slowest permeability within a depth of 40 inches:           Slowest permeability within a depth of 40 inches:
    Moderate                                                    Moderate
Permeability below a depth of 60 inches: Moderate           Permeability below a depth of 60 inches: Moderate
Depth to restrictive feature: More than 80 inches           Depth to restrictive feature: More than 80 inches
Available water capacity to a depth of 60 inches: About     Available water capacity to a depth of 60 inches: About
    12 inches                                                   12.2 inches
Content of organic matter in the surface layer: 0.5 to      Content of organic matter in the surface layer: 1 to 3
    1.0 percent                                                 percent
Shrink-swell potential: Moderate                            Shrink-swell potential: Moderate
Flooding: None                                              Flooding: None
Accelerated erosion: The surface layer is mostly            Accelerated erosion: None or slight
    subsoil material.                                       Potential for frost action: High
Potential for frost action: High                            Hazard of corrosion: Moderate for steel and moderate
Hazard of corrosion: Moderate for steel and moderate            for concrete
    for concrete                                            Surface runoff class: Medium
Surface runoff class: Medium                                Susceptibility to water erosion: High
Susceptibility to water erosion: High                       Susceptibility to wind erosion: Slight
Susceptibility to wind erosion: Very slight
                                                                             Interpretive Groups
                 Interpretive Groups
                                                            Land capability classification: 3e
Land capability classification: 4e                          Prime farmland status: Not prime farmland
Prime farmland status: Not prime farmland                   Hydric soil status: Not hydric
Hydric soil status: Not hydric

                                                            19D3—Sylvan silty clay loam, 10 to 18
19D—Sylvan silt loam, 10 to 18 percent
                                                               percent slopes, severely eroded
   slopes
                         Setting                                                     Setting
Landform: Ground moraines                                   Landform: Ground moraines
Position on the landform: Backslopes                        Position on the landform: Backslopes
                     Composition                                                 Composition
Sylvan and similar soils: 90 percent                        Sylvan and similar soils: 90 percent
Dissimilar soils: 10 percent                                Dissimilar soils: 10 percent
                 Minor Components                                            Minor Components
Similar soils:                                              Similar soils:
• Soils that are not calcareous within a depth of 40        • Soils that are not calcareous within a depth of 40
inches                                                      inches
• Soils that are underlain by glacial till within a depth   • Soils that are underlain by glacial till within a depth
of 60 inches                                                of 60 inches
• Soils having subsurface horizons that are                 • Soils having subsurface horizons that are
calcareous within a depth of 20 inches                      calcareous within a depth of 20 inches
Rock Island County, Illinois                                                                                       113




Dissimilar soils:                                           Dissimilar soils:
• The somewhat poorly drained Atlas soils on                • The somewhat poorly drained Atlas soils on
backslopes                                                  backslopes
• The well drained Thebes soils on shoulders and            • The well drained Thebes soils on shoulders and
backslopes                                                  backslopes
  Properties and Qualities of the Sylvan Soil                 Properties and Qualities of the Sylvan Soil
Parent material: Loess                                      Parent material: Loess
Drainage class: Well drained                                Drainage class: Well drained
Slowest permeability within a depth of 40 inches:           Slowest permeability within a depth of 40 inches:
    Moderate                                                    Moderate
Permeability below a depth of 60 inches: Moderate           Permeability below a depth of 60 inches: Moderate
Depth to restrictive feature: More than 80 inches           Depth to restrictive feature: More than 80 inches
Available water capacity to a depth of 60 inches: About     Available water capacity to a depth of 60 inches: About
    12.2 inches                                                 12.3 inches
Content of organic matter in the surface layer: 0.5 to      Content of organic matter in the surface layer: 1 to 3
    1.0 percent                                                 percent
Shrink-swell potential: Moderate                            Shrink-swell potential: Moderate
Flooding: None                                              Flooding: None
Accelerated erosion: The surface layer is mostly            Accelerated erosion: None or slight
    subsoil material.                                       Potential for frost action: High
Potential for frost action: High                            Hazard of corrosion: Moderate for steel and moderate
Hazard of corrosion: Moderate for steel and moderate            for concrete
    for concrete                                            Surface runoff class: High
Surface runoff class: Medium                                Susceptibility to water erosion: High
Susceptibility to water erosion: High                       Susceptibility to wind erosion: Slight
Susceptibility to wind erosion: Very slight
                                                                             Interpretive Groups
                 Interpretive Groups
                                                            Land capability classification: 6e
Land capability classification: 4e
                                                            Prime farmland status: Not prime farmland
Prime farmland status: Not prime farmland
                                                            Hydric soil status: Not hydric
Hydric soil status: Not hydric


19F—Sylvan silt loam, 18 to 35 percent                      19F3—Sylvan silty clay loam, 18 to 35
   slopes                                                      percent slopes, severely eroded
                         Setting
                                                                                     Setting
Landform: Ground moraines
                                                            Landform: Ground moraines
Position on the landform: Backslopes
                                                            Position on the landform: Backslopes
                     Composition
                                                                                 Composition
Sylvan and similar soils: 85 percent
                                                            Sylvan and similar soils: 100 percent
Dissimilar soils: 15 percent
                 Minor Components                                            Minor Components
Similar soils:                                              Similar soils:
• Soils that are not calcareous within a depth of 40        • Soils that are not calcareous within a depth of 40
inches                                                      inches
• Soils that are underlain by glacial till within a depth   • Soils that are underlain by glacial till within a depth
of 60 inches                                                of 60 inches
• Soils having subsurface horizons that are                 • Soils having subsurface horizons that are
calcareous within a depth of 20 inches                      calcareous within a depth of 20 inches
114                                                                                                  Soil Survey of




  Properties and Qualities of the Sylvan Soil                 Properties and Qualities of the Sylvan Soil
Parent material: Loess                                      Parent material: Loess
Drainage class: Well drained                                Drainage class: Well drained
Slowest permeability within a depth of 40 inches:           Slowest permeability within a depth of 40 inches:
    Moderate                                                    Moderate
Permeability below a depth of 60 inches: Moderate           Permeability below a depth of 60 inches: Moderate
Depth to restrictive feature: More than 80 inches           Depth to restrictive feature: More than 80 inches
Available water capacity to a depth of 60 inches: About     Available water capacity to a depth of 60 inches: About
    12.1 inches                                                 12.2 inches
Content of organic matter in the surface layer: 0.5 to      Content of organic matter in the surface layer: 1 to 2
    1.0 percent                                                 percent
Shrink-swell potential: Moderate                            Shrink-swell potential: Moderate
Flooding: None                                              Flooding: None
Accelerated erosion: The surface layer is mostly            Accelerated erosion: None or slight
    subsoil material.                                       Potential for frost action: High
Potential for frost action: High                            Hazard of corrosion: Moderate for steel and moderate
Hazard of corrosion: Moderate for steel and moderate            for concrete
    for concrete                                            Surface runoff class: High
Surface runoff class: High                                  Susceptibility to water erosion: High
Susceptibility to water erosion: High                       Susceptibility to wind erosion: Slight
Susceptibility to wind erosion: Very slight
                                                               Properties and Qualities of the Bold Soil
                 Interpretive Groups                        Parent material: Loess
                                                            Drainage class: Well drained
Land capability classification: 6e
                                                            Slowest permeability within a depth of 40 inches:
Prime farmland status: Not prime farmland
                                                                Moderate
Hydric soil status: Not hydric
                                                            Permeability below a depth of 60 inches: Moderate
                                                            Depth to restrictive feature: More than 80 inches
                                                            Available water capacity to a depth of 60 inches: About
962F—Sylvan-Bold silt loams, 18 to 35                           13.2 inches
   percent slopes                                           Content of organic matter in the surface layer: 0.5 to
                                                                2.0 percent
                         Setting
                                                            Shrink-swell potential: Low
Landform: Loess hills                                       Flooding: None
Position on the landform: Sylvan—upper and middle           Accelerated erosion: None or slight
    parts of backslopes; Bold—nose slopes and the           Potential for frost action: High
    middle and lower parts of backslopes                    Hazard of corrosion: Low for steel and low for concrete
                                                            Surface runoff class: High
                     Composition
                                                            Susceptibility to water erosion: High
Sylvan and similar soils: 65 percent                        Susceptibility to wind erosion: Slight
Bold and similar soils: 30 percent
                                                                            Interpretive Groups
Dissimilar soils: 5 percent
                                                            Land capability classification: Sylvan—6e; Bold—6e
                 Minor Components
                                                            Prime farmland status: Not prime farmland
Similar soils:                                              Hydric soil status: Sylvan—not hydric; Bold—not hydric
• Soils that are not calcareous within a depth of 40
inches
• Soils that are underlain by glacial till within a depth   Tell Series
of 60 inches
                                                            Taxonomic classification: Fine-silty over sandy or
Dissimilar soils:                                              sandy-skeletal, mixed, superactive, mesic Typic
• The somewhat poorly drained Orion and Radford                Hapludalfs
soils on footslopes                                         Map units in which this series occurs: 917C2, 917D2
Rock Island County, Illinois                                                                                    115




                     Typical Pedon                              Value—4 or 5
                                                                Chroma—3 or 4
Tell silt loam, 0 to 2 percent slopes; 730 feet south and
                                                                Texture—silty clay loam or silt loam
2,190 feet west of the northeast corner of sec. 7, T. 18
N., R. 6 E.; in Bureau County, Illinois; USGS Yorktown      2B horizon:
topographic quadrangle; lat. 41 degrees 34 minutes 02           Hue—7.5YR or 10YR
seconds N. and long. 89 degrees 50 minutes 55                   Value—3 to 5
seconds W., NAD 27:                                             Chroma—3 to 6
                                                                Texture—sandy loam, loam, or sandy clay loam
Ap—0 to 9 inches; dark brown (10YR 3/3) silt loam,
   pale brown (10YR 6/3) dry; weak medium granular          2C horizon:
   structure; friable; few fine roots throughout;               Hue—7.5YR or 10YR
   moderately acid; abrupt smooth boundary.                     Value—4 or 5
E—9 to 14 inches; brown (10YR 5/3) silt loam;                   Chroma—4 to 8
   moderate thin platy structure; friable; few fine roots       Texture—sand or loamy sand
   throughout; few faint dark grayish brown (10YR
   4/2) organic coatings on faces of peds; moderately
   acid; abrupt smooth boundary.                            Thebes Series
BE—14 to 20 inches; yellowish brown (10YR 5/4) silt
   loam; moderate medium subangular blocky                  Taxonomic classification: Fine-silty, mixed,
   structure; friable; few fine roots between peds; few        superactive, mesic Typic Hapludalfs
   faint dark brown (10YR 3/3) organic coatings on
                                                              Typical Pedon (Official Series Description)
   faces of peds; moderately acid; clear smooth
   boundary.                                                Thebes silt loam, 5 to 10 percent slopes; 1,060 feet
Bt—20 to 30 inches; yellowish brown (10YR 5/4) silt         west and 1,800 feet south of the northeast corner of
   loam; moderate medium subangular blocky                  sec. 3, T. 13 N., R. 3 W.; in Logan County, Illinois;
   structure; friable; few fine roots between peds;         USGS Aledo East topographic quadrangle; lat. 41
   common faint dark yellowish brown (10YR 4/4)             degrees 09 minutes 02 seconds N. and long. 90
   clay films on faces of peds; moderately acid; clear      degrees 42 minutes 30 seconds W., NAD 27:
   smooth boundary.
                                                            Ap—0 to 9 inches; dark grayish brown (10YR 4/2) silt
2BC—30 to 34 inches; yellowish brown (10YR 5/4)
                                                                loam, light brownish gray (10YR 6/2) dry;
   sandy loam; moderate medium subangular blocky
                                                                moderate medium granular structure; friable;
   structure; friable; few fine roots between peds; few
                                                                slightly acid; clear smooth boundary.
   faint dark yellowish brown (10YR 4/4) clay films on
                                                            Bt1—9 to 14 inches; yellowish brown (10YR 5/4) silty
   faces of peds; moderately acid; clear smooth
                                                                clay loam; weak fine and medium subangular
   boundary.
                                                                blocky structure; friable; few distinct brown (10YR
2C—34 to 60 inches; yellowish brown (10YR 5/4)
                                                                5/3) clay films on faces of peds; strongly acid;
   loamy sand; single grain; loose; moderately acid.
                                                                clear wavy boundary.
              Range in Characteristics                      Bt2—14 to 26 inches; dark yellowish brown (10YR 4/4)
                                                                silty clay loam; moderate medium subangular
Thickness of the loess: 20 to 36 inches
                                                                blocky structure; friable; common distinct brown
Thickness of the solum: 20 to 36 inches
                                                                (10YR 4/3) clay films on faces of peds; moderately
Ap or A horizon:                                                acid; clear wavy boundary.
    Hue—10YR                                                Bt3—26 to 31 inches; dark yellowish brown (10YR 4/4)
    Value—3 to 5                                                silty clay loam; moderate medium subangular
    Chroma—2 to 5                                               blocky structure; friable; common distinct brown
    Texture—silt loam                                           (10YR 4/3) clay films; few medium distinct pale
                                                                brown (10YR 6/3) iron depletions and few medium
E horizon (if it occurs):
                                                                distinct strong brown (7.5YR 4/6) iron
    Hue—10YR
                                                                concentrations; common dark iron-manganese
    Value—4 or 5
                                                                stains; slightly acid; clear wavy boundary.
    Chroma—2 to 4
                                                            2Bt4—31 to 40 inches; dark yellowish brown (10YR
    Texture—silt loam
                                                                4/4) loam; moderate medium subangular blocky
Bt horizon:                                                     structure; friable; few distinct brown (10YR 4/3)
    Hue—7.5YR or 10YR                                           clay films on faces of peds; common coarse
116                                                                                               Soil Survey of




   distinct pale brown (10YR 6/3) iron depletions and   212B—Thebes silt loam, 2 to 5 percent
   common coarse distinct strong brown (7.5YR 4/6)         slopes
   iron concentrations; common dark iron-
                                                                               Setting
   manganese stains; slightly acid; clear wavy
   boundary.                                            Landform: Ground moraines
2BC—40 to 50 inches; yellowish brown (10YR 5/4)         Position on the landform: Shoulders
   and brown (7.5YR 4/4), stratified sandy loam and
                                                                            Composition
   loamy sand; weak medium subangular blocky
   structure; friable; few medium distinct pale brown   Thebes and similar soils: 94 percent
   (10YR 6/3) iron depletions; moderately acid; clear   Dissimilar soils: 6 percent
   wavy boundary.
                                                                        Minor Components
2C—50 to 80 inches; dark yellowish brown (10YR
   4/4), stratified loamy sand and sand; massive;       Similar soils:
   friable; common medium and coarse distinct           • Soils that have less than 20 inches of loess at the
   brown (7.5YR 4/4) iron concentrations; slightly      surface
   acid.                                                • Soils that contain more sand throughout
             Range in Characteristics                   Dissimilar soils:
                                                        • Somewhat poorly drained soils on footslopes
Thickness of loess or silty material: 20 to 40 inches
                                                        • Poorly drained soils on toeslopes
Thickness of the solum: 25 to 55 inches
Ap or A horizon:                                         Properties and Qualities of the Thebes Soil
    Hue—10YR
                                                        Parent material: Loess over eolian sands
    Value—3 to 5
                                                        Drainage class: Well drained
    Chroma—1 to 4
                                                        Slowest permeability within a depth of 40 inches:
    Texture—silt loam or silty clay loam
                                                            Moderate
    Reaction—slightly acid or neutral
                                                        Permeability below a depth of 60 inches: Rapid
E horizon (if it occurs):                               Depth to restrictive feature: More than 80 inches
    Hue—10YR                                            Available water capacity to a depth of 60 inches: About
    Value—4 or 5                                            8.9 inches
    Chroma—3 to 6                                       Content of organic matter in the surface layer: 2 to 3
    Texture—silt loam                                       percent
    Reaction—moderately acid or slightly acid           Shrink-swell potential: Moderate
                                                        Flooding: None
Bt horizon:
                                                        Accelerated erosion: None or slight
    Hue—7.5YR or 10YR
                                                        Potential for frost action: High
    Value—4 or 5
                                                        Hazard of corrosion: Moderate for steel and moderate
    Chroma—3 to 6
                                                            for concrete
    Texture—silty clay loam or silt loam
                                                        Surface runoff class: Low
    Reaction—very strongly acid to slightly acid
                                                        Susceptibility to water erosion: Moderate
2Bt horizon:                                            Susceptibility to wind erosion: Slight
    Hue—7.5YR or 10YR
    Value—4 or 5                                                        Interpretive Groups
    Chroma—4 to 6
                                                        Land capability classification: 2e
    Texture—loam, sandy loam, fine sandy loam,
                                                        Prime farmland status: Prime farmland
      sandy clay loam, or clay loam
                                                        Hydric soil status: Not hydric
    Reaction—very strongly acid to slightly acid
2C horizon:
    Hue—7.5YR or 10YR                                   Timula Series
    Value—4 to 6
    Chroma—3 to 6                                       Taxonomic classification: Coarse-silty, mixed,
    Texture—loamy sand, fine sand, loamy fine sand,        superactive, mesic Typic Eutrudepts
      or sand that has strata in some pedons            Map units in which this series occurs: 943D2,
    Reaction—very strongly acid to slightly acid           943F2
Rock Island County, Illinois                                                                                     117




                    Typical Pedon                            Bw horizon:
                                                                Hue—10YR
Timula silt loam, in an area of Seaton-Timula silt
                                                                Value—4 to 6
loams, 18 to 30 percent slopes, eroded; 1,080 feet
                                                                Chroma—3 to 6
east and 2,000 feet south of the northwest corner of
                                                                Texture—silt loam or silt
sec. 29, T. 22 N., R. 5 E.; in Whiteside County, Illinois;
USGS Morrison topographic quadrangle; lat. 41                BC, Bk, or C horizon:
degrees 52 minutes 03 seconds N. and long. 89                    Hue—10YR, 2.5Y, or 5Y
degrees 57 minutes 19 seconds W., NAD 27:                        Value—5 or 6
                                                                 Chroma—2 to 4
Ap—0 to 6 inches; brown (10YR 4/3) silt loam, pale
                                                                 Texture—silt loam or silt
   brown (10YR 6/3) dry; weak fine subangular
   blocky structure parting to weak medium granular;
   friable; few fine roots throughout; few dark
   yellowish brown (10YR 4/4) fragments of subsoil           Titus Series
   material; neutral; abrupt smooth boundary.
                                                             Taxonomic classification: Fine, smectitic, mesic Vertic
Bw1—6 to 12 inches; yellowish brown (10YR 5/4) silt
                                                                Endoaquolls
   loam; moderate medium and fine subangular
   blocky structure; friable; few fine roots between                            Typical Pedon
   peds; few faint brown (10YR 4/3) organic coatings
                                                             Titus silty clay loam, 0 to 2 percent slopes, frequently
   and dark yellowish brown (10YR 4/4) films on
                                                             flooded; 20 feet west and 10 feet north of the
   faces of peds; neutral; clear smooth boundary.
                                                             southeast corner of sec. 28, T. 20 N., R. 3 E.; in Henry
Bw2—12 to 23 inches; yellowish brown (10YR 5/4) silt
                                                             County, Illinois; USGS Erie Northwest topographic
   loam; weak coarse and medium subangular blocky
                                                             quadrangle; lat. 41 degrees 41 minutes 10 seconds N.
   structure; friable; few fine roots between peds;
                                                             and long. 90 degrees 09 minutes 01 second W., NAD
   common faint dark yellowish brown (10YR 4/4) films
                                                             27:
   on faces of peds; neutral; clear smooth boundary.
BC—23 to 28 inches; yellowish brown (10YR 5/4) silt          Ap—0 to 8 inches; black (10YR 2/1) silty clay loam,
   loam; weak coarse angular blocky structure;                  very dark gray (10YR 3/1) dry; weak medium
   friable; few fine distinct yellowish brown (10YR             subangular blocky structure parting to moderate
   5/6) iron oxide masses in the matrix and light               fine granular; friable; few fine roots throughout;
   brownish gray (10YR 6/2) iron depletions; slightly           neutral; abrupt smooth boundary.
   effervescent; slightly alkaline; gradual smooth           A1—8 to 17 inches; very dark gray (10YR 3/1) silty
   boundary.                                                    clay loam, dark gray (10YR 4/1) dry; moderate
C—28 to 60 inches; light yellowish brown (2.5Y 6/4)             medium and fine subangular blocky structure;
   silt loam; massive; friable; common fine prominent           friable; few fine roots throughout; many faint black
   yellowish brown (10YR 5/6) iron masses in the                (10YR 2/1) organic coatings on faces of peds; few
   matrix and common fine distinct light gray (10YR             prominent dark brown (7.5YR 3/4) concretions of
   7/2) iron depletions; few fine soft masses of iron;          iron throughout; neutral; clear smooth boundary.
   strongly effervescent; slightly alkaline.                 A2—17 to 22 inches; very dark gray (10YR 3/1) silty
                                                                clay loam, dark gray (10YR 4/1) dry; strong
             Range in Characteristics
                                                                medium and fine angular blocky structure; firm;
Thickness of the solum: 18 to 40 inches                         few fine roots between peds; many faint black
Depth to carbonates: 18 to 40 inches                            (10YR 2/1) organic coatings on faces of peds; few
                                                                prominent reddish brown (5YR 4/4) soft masses of
Ap or A horizon:
                                                                iron and few prominent dark brown (7.5YR 3/4)
    Hue—10YR
                                                                concretions of iron throughout; neutral; clear
    Value—3 or 4
                                                                smooth boundary.
    Chroma—1 to 3
                                                             Bg1—22 to 32 inches; dark gray (10YR 4/1) silty clay;
    Texture—silt loam or silt
                                                                strong medium and fine prismatic structure; firm;
E horizon (if it occurs):                                       few faint very dark gray (10YR 3/1) organic
    Hue—10YR                                                    coatings and few prominent dark brown (7.5YR
    Value—4 or 5                                                3/4) coatings of iron-manganese on faces of peds;
    Chroma—2 to 4                                               few prominent reddish brown (5YR 4/4) soft
    Texture—silt loam or silt                                   masses of iron and dark brown (7.5YR 3/4)
118                                                                                                 Soil Survey of




   concretions of iron in the matrix; few fine                 Value—4 to 6
   prominent strong brown (7.5YR 5/6) iron masses              Chroma—1 or 2
   in the matrix; neutral; clear smooth boundary.              Texture—silty clay loam; thin strata in some
Bg2—32 to 46 inches; dark gray (10YR 4/1) silty clay             pedons
   loam; moderate medium prismatic structure
   parting to moderate coarse subangular blocky;
   firm; few faint very dark gray (10YR 3/1) organic       8404A—Titus silty clay loam, 0 to 2
   coatings on faces of peds; strata of mixed dark            percent slopes, occasionally flooded
   gray (10YR 4/1) and strong brown (7.5YR 5/6)
   silty clay loam 1 inch thick at a depth of 39 inches;                            Setting
   common fine prominent strong brown (7.5YR 5/6)
                                                           Landform: Flood plains
   iron masses in the matrix; neutral; clear smooth
   boundary.                                                                   Composition
Bg3—46 to 52 inches; grayish brown (2.5Y 5/2) silty
                                                           Titus and similar soils: 90 percent
   clay loam; moderate coarse and medium
                                                           Dissimilar soils: 10 percent
   subangular blocky structure; friable; few distinct
   pressure faces; common fine prominent strong                            Minor Components
   brown (7.5YR 4/6 and 5/6) and yellowish brown
                                                           Similar soils:
   (10YR 5/4) iron masses in the matrix; neutral;
                                                           • Soils that have less clay and more sand in the
   clear smooth boundary.
                                                           subsoil
BCg—52 to 60 inches; stratified grayish brown (2.5Y
   5/2) silty clay loam and clay loam; weak coarse         Dissimilar soils:
   angular blocky structure; friable; few fine distinct    • Well drained soils on summits
   dark gray (10YR 4/1) iron depletions and common         • Soils that are calcareous
   medium prominent strong brown (7.5YR 4/6) and
   common fine prominent yellowish brown (10YR                Properties and Qualities of the Titus Soil
   5/4) iron masses in the matrix; few prominent dark
                                                           Parent material: Clayey alluvium
   brown (7.5YR 3/4) concretions of iron throughout;
                                                           Drainage class: Poorly drained
   neutral; clear smooth boundary.
                                                           Slowest permeability within a depth of 40 inches: Slow
Cg—60 to 80 inches; stratified grayish brown (2.5Y
                                                           Permeability below a depth of 60 inches: Slow or
   5/2) silty clay loam and clay loam; massive; friable;
                                                               moderately slow
   few fine distinct dark gray (10YR 4/1) iron
                                                           Depth to restrictive feature: More than 80 inches
   depletions and common medium prominent strong
                                                           Available water capacity to a depth of 60 inches: About
   brown (7.5YR 4/6) and common fine prominent
                                                               10.6 inches
   yellowish brown (10YR 5/4) iron oxide masses in
                                                           Content of organic matter in the surface layer: 2 to 4
   the matrix; few hard masses of iron; neutral.
                                                               percent
             Range in Characteristics                      Shrink-swell potential: High
                                                           Depth and months of the highest apparent seasonal
Thickness of the mollic epipedon: 10 to 24 inches
                                                               high water table: At the surface, January to May
Thickness of the solum: 35 to 60 inches
                                                           Ponding depth: 0.2 foot during wet periods
Ap or A horizon:                                           Frequency and most likely period of flooding:
    Hue—10YR, 5Y, or N                                         Occasional, November to June
    Value—2 or 3                                           Potential for frost action: High
    Chroma—0 to 2                                          Hazard of corrosion: High for steel and low for
    Texture—silty clay loam or silty clay                      concrete
                                                           Surface runoff class: Negligible
Bg horizon:
                                                           Susceptibility to water erosion: Slight
    Hue—10YR, 2.5Y, 5Y, or N
                                                           Susceptibility to wind erosion: Moderate
    Value—4 to 6
    Chroma—0 to 2                                                          Interpretive Groups
    Texture—silty clay loam or silty clay
                                                           Land capability classification: 3w
BCg and/or Cg horizon:                                     Prime farmland status: Prime farmland where drained
   Hue—10YR, 2.5Y, or 5Y                                   Hydric soil status: Hydric
Rock Island County, Illinois                                                                                     119




Velma Series                                                             Range in Characteristics
                                                             Thickness of the mollic epipedon: 10 to 24 inches
Taxonomic classification: Fine-loamy, mixed,
                                                             Thickness of the loess: 0 to 20 inches
   superactive, mesic Typic Argiudolls
                                                             Thickness of the solum: 42 to more than 60 inches
                    Typical Pedon                            Depth to carbonates: 42 to 60 inches
Velma silt loam, 10 to 18 percent slopes, eroded;            Ap or A horizon:
1,880 feet north and 260 feet east of the southwest              Hue—10YR
corner of sec. 25, T. 14 N., R. 3 E.; in Henry County,           Value—2 or 3
Illinois; USGS Galva topographic quadrangle; 41                  Chroma—1 to 3
degrees 10 minutes 12 seconds N. and long. 90                    Texture—silt loam or loam
degrees 06 minutes 52 seconds W., NAD 27:
                                                             Bt or 2Bt horizon:
Ap—0 to 10 inches; very dark gray (10YR 3/1) and                 Hue—7.5YR or 10YR
    dark brown (10YR 3/3) silt loam, dark grayish                Value—4 or 5
    brown (10YR 4/2) dry; weak fine and medium                   Chroma—3 to 8
    granular structure; friable; strongly acid; abrupt           Texture—clay loam or loam
    smooth boundary.
                                                             C or 2C horizon:
AB—10 to 13 inches; dark brown (10YR 3/3) and very
                                                                 Hue—7.5YR or 10YR
    dark gray (10YR 3/1) silt loam, grayish brown
                                                                 Value—5 or 6
    (10YR 5/2) and brown (10YR 5/3) dry; weak
                                                                 Chroma—3 to 8
    medium subangular blocky structure parting to
                                                                 Texture—clay loam, loam, or sandy loam
    weak fine and medium granular; friable; strongly
    acid; clear smooth boundary.
2Bt1—13 to 18 inches; dark yellowish brown (10YR
    4/4) and yellowish brown (10YR 5/6) clay loam;           250D—Velma silt loam, 10 to 18 percent
    weak medium subangular blocky structure; friable;           slopes
    prominent dark grayish brown (10YR 4/2) clay                                    Setting
    films; prominent very dark grayish brown (10YR
                                                             Landform: Ground moraines
    3/2) organic coatings; strongly acid; abrupt smooth
                                                             Position on the landform: Backslopes
    boundary.
2Bt2—18 to 22 inches; yellowish brown (10YR 5/6 and                              Composition
    5/8) clay loam; weak medium subangular blocky
                                                             Velma and similar soils: 97 percent
    structure; friable; prominent brown (10YR 4/3) clay
                                                             Dissimilar soils: 3 percent
    films; strongly acid; clear smooth boundary.
2Bt3—22 to 27 inches; yellowish brown (10YR 5/4)                             Minor Components
    clay loam; moderate medium subangular blocky
                                                             Similar soils:
    structure; friable; prominent brown (10YR 4/3) clay
                                                             • Soils that have a lighter colored or thinner surface
    films; few fine faint brownish yellow (10YR 6/8)
                                                             layer
    iron accumulations; neutral; clear smooth
                                                             • Soils that have more than 20 inches of loess at the
    boundary.
                                                             surface
2Bt4—27 to 34 inches; yellowish brown (10YR 5/4 and
    5/6) clay loam; moderate medium and coarse               Dissimilar soils:
    subangular and angular blocky structure; firm;           • Soils that have a seasonal high water table within a
    prominent brown (10YR 4/3) clay films; few               depth of 60 inches
    medium distinct light brownish gray (10YR 6/2)           • The somewhat poorly drained Radford soils on
    iron depletions; neutral; clear smooth boundary.         toeslopes
2BC—34 to 44 inches; pale brown (10YR 6/3) and
                                                               Properties and Qualities of the Velma Soil
    yellowish brown (10YR 5/6) clay loam; moderate
    medium and coarse angular blocky structure; firm;        Parent material: Till
    neutral; clear smooth boundary.                          Drainage class: Well drained
2C—44 to 60 inches; yellowish brown (10YR 5/4 and            Slowest permeability within a depth of 40 inches:
    5/6) clay loam; massive; firm; few fine distinct light       Moderate
    gray (5Y 7/1) iron depletions; slightly alkaline.        Permeability below a depth of 60 inches: Moderate
120                                                                                                Soil Survey of




Depth to restrictive feature: More than 80 inches         Accelerated erosion: The surface layer has been
Available water capacity to a depth of 60 inches: About       thinned by erosion.
    10.4 inches                                           Potential for frost action: Moderate
Content of organic matter in the surface layer: 3 to 4    Hazard of corrosion: High for steel and high for
    percent                                                   concrete
Shrink-swell potential: Moderate                          Surface runoff class: Medium
Flooding: None                                            Susceptibility to water erosion: High
Accelerated erosion: None or slight                       Susceptibility to wind erosion: Slight
Potential for frost action: Moderate
                                                                   Properties and Qualities of the
Hazard of corrosion: High for steel and high for
                                                                           Coatsburg Soil
    concrete
Surface runoff class: Medium                              Parent material: Till
Susceptibility to water erosion: Moderate                 Drainage class: Poorly drained
Susceptibility to wind erosion: Slight                    Slowest permeability within a depth of 40 inches: Very
                                                              slow
                Interpretive Groups
                                                          Permeability below a depth of 60 inches: Slow
Land capability classification: 3e                        Depth to restrictive feature: More than 80 inches
Prime farmland status: Not prime farmland                 Available water capacity to a depth of 60 inches: About
Hydric soil status: Not hydric                                8.5 inches
                                                          Content of organic matter in the surface layer: 3 to 5
                                                              percent
944D2—Velma-Coatsburg silt loams, 10 to                   Shrink-swell potential: High
   18 percent slopes, eroded                              Depth and months of the highest perched seasonal
                                                              high water table: At the surface, January to May
                       Setting                            Flooding: None
                                                          Accelerated erosion: The surface layer has been
Landform: Ground moraines
                                                              thinned by erosion.
Position on the landform: Velma—lower and middle
                                                          Potential for frost action: High
    parts of backslopes; Coatsburg—upper and
                                                          Hazard of corrosion: High for steel and moderate for
    middle parts of backslopes
                                                              concrete
                    Composition                           Surface runoff class: High
                                                          Susceptibility to water erosion: High
Velma and similar soils: 60 percent
                                                          Susceptibility to wind erosion: Slight
Coatsburg and similar soils: 40 percent
                                                                          Interpretive Groups
                Minor Components
                                                          Land capability classification: Velma—3e; Coatsburg—
Similar soils:
                                                              4e
• Soils that have a lighter colored or thinner surface
                                                          Prime farmland status: Not prime farmland
layer
                                                          Hydric soil status: Velma—not hydric; Coatsburg—
• Soils that have more than 20 inches of loess at the
                                                              hydric
surface
  Properties and Qualities of the Velma Soil
                                                          Wabash Series
Parent material: Till
Drainage class: Well drained                              Taxonomic classification: Fine, smectitic, mesic
Slowest permeability within a depth of 40 inches:            Cumulic Vertic Endoaquolls
    Moderate
                                                                             Typical Pedon
Permeability below a depth of 60 inches: Moderate
Depth to restrictive feature: More than 80 inches         Wabash silty clay, 0 to 2 percent slopes, rarely
Available water capacity to a depth of 60 inches: About   flooded; 2,620 feet south and 1,340 feet east of the
    10.7 inches                                           northwest corner of sec. 36, T. 16 N., R. 6 W.; in
Content of organic matter in the surface layer: 3 to 4    Mercer County, Illinois; USGS Blanchard Island
    percent                                               topographic quadrangle; lat. 41 degrees 20 minutes 02
Shrink-swell potential: Moderate                          seconds N. and long. 91 degrees 01 minute 06
Flooding: None                                            seconds W., NAD 27:
Rock Island County, Illinois                                                                                       121




Ap—0 to 6 inches; black (2.5Y 2.5/1) silty clay;             3083A—Wabash silty clay, 0 to 2 percent
   moderate medium and coarse subangular blocky                 slopes, frequently flooded
   and angular blocky structure; firm; neutral; abrupt
   smooth boundary.                                                                   Setting
A—6 to 15 inches; black (2.5Y 2.5/1) silty clay;
                                                             Landform: Flood plains
   moderate medium and coarse subangular blocky
   and angular blocky structure; firm; neutral; clear                             Composition
   smooth boundary.
                                                             Wabash and similar soils: 100 percent
Bg1—15 to 32 inches; black (2.5Y 2.5/1) clay;
   moderate medium prismatic structure parting to
                                                                              Minor Components
   moderate coarse subangular blocky; firm; olive
   (5Y 4/4) root linings in the lower part; neutral; clear   Similar soils:
   smooth boundary.                                          • Soils that have less clay in the subsoil
Bg2—32 to 40 inches; mixed black (2.5Y 2.5/1) and            • Soils that have a surface layer less than 24 inches
   dark gray (5Y 4/1) clay; weak medium prismatic            thick
   structure parting to moderate medium                      • Soils that are calcareous in all or part of the control
   subangular blocky; firm; many fine distinct olive         section
   (5Y 4/4) and many fine prominent brownish yellow
                                                                      Properties and Qualities of the
   (10YR 6/8) redoximorphic features; common fine
                                                                               Wabash Soil
   prominent white (10YR 8/1) redoximorphic
   features lining root channels; neutral; abrupt            Parent material: Clayey alluvium
   smooth boundary.                                          Drainage class: Poorly drained
Cg—40 to 63 inches; dark gray (10YR 4/1), olive              Slowest permeability within a depth of 40 inches: Very
   brown (2.5Y 4/4), olive gray (5Y 5/2), and olive              slow
   (5Y 5/3) clay loam; weak coarse subangular                Permeability below a depth of 60 inches: Very slow
   blocky structure in the upper half; firm; many            Depth to restrictive feature: More than 80 inches
   fine faint olive (5Y 4/4) and many fine distinct          Available water capacity to a depth of 60 inches: About
   brownish yellow (10YR 6/8) redoximorphic                      6.4 inches
   features; common fine prominent white (10YR               Content of organic matter in the surface layer: 2 to 4
   8/1) redoximorphic features lining root channels;             percent
   abundant snail shells in the upper half and few in        Shrink-swell potential: Very high
   the lower half; moderately alkaline.                      Depth and months of the highest apparent seasonal
                                                                 high water table: At the surface, January to
             Range in Characteristics
                                                                 May
Thickness of the mollic epipedon: More than 36               Ponding depth: 0.2 foot during wet periods
    inches                                                   Frequency and most likely period of flooding:
Thickness of the solum: 40 to 60 inches                          Frequent, November to June
                                                             Potential for frost action: High
Ap and A horizons:
                                                             Hazard of corrosion: High for steel and moderate for
    Hue—10YR to 5Y or N
                                                                 concrete
    Value—2 or 3
                                                             Surface runoff class: Negligible
    Chroma—0 to 2
                                                             Susceptibility to water erosion: Slight
    Texture—silty clay or clay
                                                             Susceptibility to wind erosion: Moderate
Bg horizon (upper part):
    Hue—10YR to 5Y or N                                                      Interpretive Groups
    Value—2 or 3
                                                             Land capability classification: 3w
    Chroma—0 to 2
                                                             Prime farmland status: Prime farmland where
Bg horizon (lower part):                                         drained and either protected from flooding or
    Hue—10YR to 5Y or N                                          not frequently flooded during the growing
    Value—2 to 5                                                 season
    Chroma—0 to 2                                            Hydric soil status: Hydric
122                                                                                                   Soil Survey of




7083A—Wabash silty clay, 0 to 2 percent                                        Typical Pedon
   slopes, rarely flooded                                   Waukee loam, 0 to 2 percent slopes; 180 feet north
                                                            and 360 feet west of the southeast corner of sec. 36, T.
                         Setting
                                                            21 N., R. 7 E.; in Whiteside County, Illinois; USGS
Landform: Flood plains                                      Sterling topographic quadrangle; lat. 41 degrees 45
                                                            minutes 30 seconds N. and long. 89 degrees 37
                     Composition
                                                            minutes 57 seconds W., NAD 27:
Wabash and similar soils: 100 percent
                                                            Ap—0 to 8 inches; very dark brown (10YR 2/2) loam,
                 Minor Components                              very dark grayish brown (10YR 3/2) dry; weak fine
                                                               subangular blocky structure parting to weak fine
Similar soils:
                                                               granular; friable; few fine roots throughout; slightly
• Soils that have less clay in the subsoil
                                                               acid; clear smooth boundary.
• Soils that have a surface layer less than 24 inches
                                                            A—8 to 14 inches; very dark grayish brown (10YR 3/2)
thick
                                                               loam, brown (10YR 4/3) dry; moderate fine and
• Soils that are calcareous in all or part of the control
                                                               medium subangular blocky structure parting to
section
                                                               moderate fine granular; friable; few fine roots
 Properties and Qualities of the Wabash Soil                   throughout; slightly acid; clear smooth boundary.
                                                            BA—14 to 19 inches; brown (10YR 4/3) loam;
Parent material: Alluvium
                                                               moderate medium subangular blocky structure;
Drainage class: Poorly drained
                                                               friable; few fine roots between peds; many faint
Slowest permeability within a depth of 40 inches: Very
                                                               dark brown (10YR 3/3) organic coatings on faces
    slow
                                                               of peds; slightly acid; clear smooth boundary.
Permeability below a depth of 60 inches: Very slow
                                                            Bw1—19 to 27 inches; dark yellowish brown (10YR
Depth to restrictive feature: More than 80 inches
                                                               4/4) loam; moderate medium subangular blocky
Available water capacity to a depth of 60 inches: About
                                                               structure; friable; few fine roots between peds; few
    6.4 inches
                                                               faint brown (10YR 4/3) coatings on faces of peds;
Content of organic matter in the surface layer: 2 to 4
                                                               slightly acid; abrupt smooth boundary.
    percent
                                                            Bw2—27 to 34 inches; dark yellowish brown (10YR
Shrink-swell potential: Very high
                                                               4/4) sandy clay loam; weak medium subangular
Depth and months of the highest apparent seasonal
                                                               blocky structure; friable; few fine roots between
    high water table: At the surface, January to
                                                               peds; few faint brown (10YR 4/3) coatings on
    May
                                                               faces of peds; about 5 to 10 percent gravel;
Ponding depth: 0.3 foot during wet periods
                                                               moderately acid; abrupt smooth boundary.
Frequency and most likely period of flooding: Rare,
                                                            2BC—34 to 43 inches; brown (7.5YR 4/4) and
    November to June
                                                               yellowish brown (10YR 5/6) loamy coarse sand;
Potential for frost action: High
                                                               weak medium subangular blocky structure; very
Hazard of corrosion: High for steel and moderate for
                                                               friable; about 8 to 12 percent gravel; moderately
    concrete
                                                               acid; abrupt smooth boundary.
Surface runoff class: Negligible
                                                            2C1—43 to 56 inches; brown (7.5YR 4/4) and
Susceptibility to water erosion: Slight
                                                               yellowish brown (10YR 5/6) coarse sand; single
Susceptibility to wind erosion: Moderate
                                                               grain; loose; about 5 to 10 percent gravel;
                Interpretive Groups                            moderately acid; abrupt smooth boundary.
                                                            2C2—56 to 60 inches; yellowish brown (10YR 5/8)
Land capability classification: 3w
                                                               sand; single grain; loose; few pebbles; slightly acid.
Prime farmland status: Prime farmland where drained
Hydric soil status: Hydric
                                                                         Range in Characteristics
                                                            Depth to sand and gravel: 24 to 40 inches
Waukee Series                                               Depth to carbonates: 72 inches or more
Taxonomic classification: Fine-loamy over sandy or          A or Ap horizon:
   sandy-skeletal, mixed, superactive, mesic Typic              Hue—10YR
   Hapludolls                                                   Value—2
Rock Island County, Illinois                                                                               123




    Chroma—1 or 2                                       • Soils that have a seasonal high water table within a
    Texture—loam or silt loam                           depth of 60 inches
Bw horizon:                                             Dissimilar soils:
   Hue—7.5YR or 10YR                                    • The somewhat poorly drained Hoopeston soils on
   Value—3 to 5                                         footslopes
   Chroma—3 to 6                                        • The poorly drained Lawler soils on toeslopes
   Texture—loam or sandy clay loam that has thin
                                                         Properties and Qualities of the Waukee Soil
      strata of sandy loam in some pedons
                                                        Parent material: Outwash
2BC and 2C horizons:
                                                        Drainage class: Well drained
   Hue—7.5YR or 10YR
                                                        Slowest permeability within a depth of 40 inches:
   Value—4 to 6
                                                            Moderate
   Chroma—3 to 8
                                                        Permeability below a depth of 60 inches: Rapid
   Texture—loamy sand, loamy coarse sand, coarse
                                                        Depth to restrictive feature: More than 80 inches
     sand, or the gravelly analogs of these textures;
                                                        Available water capacity to a depth of 60 inches: About
     some pedons contain thin strata with 20 to 50
                                                            7.4 inches
     percent gravel
                                                        Content of organic matter in the surface layer: 3 to 4
                                                            percent
                                                        Shrink-swell potential: Low
727A—Waukee loam, 0 to 2 percent                        Flooding: None
   slopes                                               Accelerated erosion: None or slight
                        Setting                         Potential for frost action: Moderate
                                                        Hazard of corrosion: Low for steel and moderate for
Landform: Outwash plains
                                                            concrete
                    Composition                         Surface runoff class: Low
                                                        Susceptibility to water erosion: Slight
Waukee and similar soils: 90 percent
                                                        Susceptibility to wind erosion: Slight
Dissimilar soils: 10 percent
                                                                        Interpretive Groups
                Minor Components
                                                        Land capability classification: 2s
Similar soils:                                          Prime farmland status: Prime farmland
• Soils that have more sand in the upper part           Hydric soil status: Not hydric
                                                                                                                     125




Use and Management of the Soils
    This soil survey is an inventory and evaluation of        indicate the severity of those limitations. The ratings in
the soils in the survey area. It can be used to adjust        these tables are both verbal and numerical.
land uses to the limitations and potentials of natural
resources and the environment. Also, it can help to           Rating Class Terms
prevent soil-related failures in land uses.
    In preparing a soil survey, soil scientists,                  Rating classes are expressed in the tables in terms
conservationists, engineers, and others collect               that indicate the extent to which the soils are limited by
extensive field data about the nature and behavioral          all of the soil features that affect a specified use or in
characteristics of the soils. They collect data on            terms that indicate the suitability of the soils for the
erosion, droughtiness, flooding, and other factors that       use. Thus, the tables may show limitation classes or
affect various soil uses and management. Field                suitability classes. Terms for the limitation classes are
experience and collected data on soil properties and          not limited, somewhat limited, and very limited. The
performance are used as a basis in predicting soil            suitability ratings are expressed as well suited,
behavior.                                                     moderately suited, poorly suited, and unsuited or as
    Information in this section can be used to plan the       good, fair, poor, and very poor.
use and management of soils for crops and pasture;
as forestland; as sites for buildings, sanitary facilities,   Numerical Ratings
highways and other transportation systems, and parks
and other recreational facilities; and as wildlife habitat.       Numerical ratings in the tables indicate the relative
It can be used to identify the potentials and limitations     severity of individual limitations. The ratings are shown
of each soil for specific land uses and to help prevent       as decimal fractions ranging from 0.00 to 1.00. They
construction failures caused by unfavorable soil              indicate gradations between the point at which a soil
properties.                                                   feature has the greatest negative impact on the use
    Planners and others using soil survey information         and the point at which the soil feature is not a
can evaluate the effect of specific land uses on              limitation. The limitations appear in order from the
productivity and on the environment. The survey can           most limiting to the least limiting. Thus, if more than
help planners to maintain or create a land use pattern        one limitation is identified, the most severe limitation is
in harmony with the natural soil.                             listed first and the least severe one is listed last.
    Contractors can use this survey to locate sources
of sand, reclamation material, roadfill, and topsoil.         Crops and Pasture
They can use it to identify areas where bedrock,
wetness, or very firm soil layers can cause difficulty in         General management needed for crops and pasture
excavation.                                                   is suggested in this section. The estimated yields of
    Health officials, highway officials, engineers, and       the main crops and pasture plants are listed, the
others may also find this survey useful. The survey           system of land capability classification used by the
can help them plan the safe disposal of wastes and            Natural Resources Conservation Service is explained,
locate sites for pavements, sidewalks, campgrounds,           and prime farmland is described.
playgrounds, lawns, and trees and shrubs.                         Planners of management systems for individual
                                                              fields or farms should consider the detailed
Interpretive Ratings                                          information given in the description of each soil under
                                                              the heading “Soil Series and Detailed Soil Map Units.”
   The interpretive tables in this survey rate the soils in   Specific information can be obtained from the local
the survey area for various uses. Many of the tables          office of the Natural Resources Conservation Service
identify the limitations that affect specified uses and       or the Cooperative Extension Service.
126                                                                                                       Soil Survey of




Crop Yield Estimates                                          Conservation Service or of the Cooperative Extension
                                                              Service can provide information about forage yields
    The average yields per acre that can be expected          other than those shown in table 6.
of the principal crops under a high level of
management are shown in table 6. In any given year,           Land Capability Classification
yields may be higher or lower than those indicated in
the table because of variations in rainfall and other             Land capability classification shows, in a general
climatic factors. The land capability classification of the   way, the suitability of soils for most kinds of field crops.
soils also is shown in the table.                             Crops that require special management are excluded.
    The yields are based mainly on the experience and         The soils are grouped according to their limitations for
records of farmers, conservationists, and extension           field crops, the risk of damage if they are used for
agents (Fehrenbacher and others, 1978). Available             crops, and the way they respond to management. The
yield data from nearby counties and results of field          criteria used in grouping the soils do not take into
trials and demonstrations also are considered.                account major and generally expensive landshaping
    The management needed to obtain the indicated             that would change slope, depth, or other
yields of the various crops depends on the kind of soil       characteristics of the soils, nor do they include
and the crop. Management can include drainage;                possible but unlikely major reclamation projects.
erosion control; protection from flooding; the proper         Capability classification is not a substitute for
planting and seeding rates; suitable high-yielding crop       interpretations designed to show suitability and
varieties; appropriate and timely tillage; control of         limitations of groups of soils for forestland or for
weeds, plant diseases, and harmful insects; favorable         engineering purposes.
soil reaction and optimum levels of nitrogen,                     In the capability system, soils generally are grouped
phosphorus, potassium, and trace elements for each            at three levels—capability class, subclass, and unit
crop; effective use of crop residue, barnyard manure,         (USDA, 1961). These categories indicate the degree
and green manure crops; and harvesting that ensures           and kinds of limitations affecting mechanized farming
the smallest possible loss.                                   systems that produce the more commonly grown field
    The estimated yields reflect the productive capacity      crops, such as corn, soybeans, small grain, and hay.
of each soil for each of the principal crops. Yields are      Only class and subclass are used in this survey.
likely to increase as new production technology is                Capability classes, the broadest groups, are
developed. The relative productivity of a given soil          designated by the numbers 1 through 8. The numbers
compared with that of other soils, however, is not likely     indicate progressively greater limitations and narrower
to change.                                                    choices for practical use.
    Crops other than those shown in the table are                 If properly managed, soils in classes 1, 2, 3, and 4
grown in the survey area, but estimated yields are not        are suitable for the mechanized production of
listed because the acreage of such crops is small. The        commonly grown field crops and for pasture and
local office of the Natural Resources Conservation            forestland. The degree of the soil limitations affecting
Service or of the Cooperative Extension Service can           the production of cultivated crops increases
provide information about the management and                  progressively from class 1 to class 4. The limitations
productivity of the soils for those crops.                    can affect levels of production and the risk of
    Pasture yields.—Under good management, proper             permanent soil deterioration caused by erosion and
grazing is essential for the production of high-quality       other factors.
forage, stand survival, and erosion control. Proper               Soils in classes 5, 6, and 7 are generally not suited
grazing helps plants to maintain sufficient and               to the mechanized production of commonly grown field
generally vigorous top growth during the growing              crops without special management, but they are
season. Brush control is essential in many areas, and         suitable for plants that provide a permanent cover,
weed control generally is needed. Rotation grazing            such as grasses and trees. The severity of the soil
and renovation also are important management                  limitations affecting crops increases progressively
practices.                                                    from class 5 to class 7. The local office of the
    Yield estimates are often provided in animal unit         Cooperative Extension Service or the Natural
months (AUM), or the amount of forage or feed                 Resources Conservation Service can provide
required to feed one animal unit (one cow, one horse,         guidance on the use of these soils as cropland.
one mule, five sheep, or five goats) for 30 days.                 Areas in class 8 are generally not suited to crops,
    The local office of the Natural Resources                 pasture, or forestland without a level of management
Rock Island County, Illinois                                                                                        127




that is impractical. These areas may have potential for      as housing, industrial, and commercial sites, sites for
other uses, such as recreational facilities and wildlife     institutions or public buildings, small parks, golf
habitat.                                                     courses, cemeteries, railroad yards, airports, sanitary
    Capability subclasses identify the dominant kind of      landfills, sewage treatment plants, and water-control
limitation in the class. They are designated by adding a     structures. Public land is land not available for farming
small letter, e, w, s, or c, to the class numeral, for       in national forests, national parks, military
example, 2e. The letter e shows that the main hazard         reservations, and state parks.
is the risk of erosion unless a close-growing plant             Prime farmland soils commonly receive an
cover is maintained; w shows that water in or on the         adequate and dependable supply of moisture from
soil interferes with plant growth or cultivation (in some    precipitation or irrigation. The temperature and growing
soils the wetness can be partly corrected by artificial      season are favorable, and the level of acidity or
drainage); s shows that the soil is limited mainly           alkalinity and the content of salts and sodium are
because it is shallow, droughty, or stony; and c, used       acceptable. The soils have few, if any, rocks and are
in only some parts of the United States, shows that the      permeable to water and air. They are not excessively
chief limitation is climate that is very cold or very dry.   erodible or saturated with water for long periods, and
    There are no subclasses in class 1 because the           they are not frequently flooded during the growing
soils of this class have few limitations. Class 5            season or are protected from flooding. Slopes range
contains only the subclasses indicated by w, s, or c         mainly from 0 to 6 percent.
because the soils in class 5 are subject to little or no        Soils that have a high water table, are subject to
erosion. They have other limitations that restrict their     flooding, or are droughty may qualify as prime
use to pasture, forestland, wildlife habitat, or             farmland where these limitations are overcome by
recreation.                                                  drainage measures, flood control, or irrigation. Onsite
    The capability classification of the soils in the        evaluation is necessary to determine the effectiveness
survey area is given in table 6.                             of corrective measures. More information about the
                                                             criteria for prime farmland can be obtained at the local
Prime Farmland                                               office of the Natural Resources Conservation Service.
                                                                A recent trend in land use has been the conversion
   Prime farmland is of major importance in meeting          of prime farmland to urban and industrial uses. The
the Nation’s short- and long-range needs for food and        loss of prime farmland to other uses puts pressure on
fiber. The acreage of high-quality farmland is limited,      lands that are less productive than prime farmland.
and the U.S. Department of Agriculture recognizes               About 157,918 acres in the survey area, or nearly
that government at local, State, and Federal levels, as      55 percent of the total acreage, meets the soil
well as individuals, should encourage and facilitate the     requirements for prime farmland.
wise use of our Nation’s prime farmland.                        The map units in the survey area that meet the
   Prime farmland soils, as defined by the U.S.              criteria for prime farmland are listed in table 7. This list
Department of Agriculture, are soils that are best           does not constitute a recommendation for a particular
suited to food, feed, forage, fiber, and oilseed crops.      land use. On some soils included in the table,
Such soils have properties that favor the economic           measures that overcome limitations are needed. The
production of sustained high yields of crops. The soils      need for these measures is indicated in parentheses
need only to be treated and managed by acceptable            after the map unit name. The location of each map unit
farming methods. An adequate moisture supply and a           is shown on the detailed soil maps. The soil qualities
sufficiently long growing season are required. Prime         that affect use and management are described in the
farmland soils produce the highest yields with minimal       section “Soil Series and Detailed Soil Map Units.”
expenditure of energy and economic resources, and
farming these soils results in the least damage to the
environment.                                                 Forestland Management and
   Prime farmland soils may presently be used as             Productivity
cropland, pasture, or forestland or for other purposes.
They either are used for food and fiber or are available        The tables in this section can help forest owners or
for these uses. Urban or built-up land, public land, and     managers plan the use of soils for wood crops. They
water areas cannot be considered prime farmland.             show the potential productivity of the soils for wood
Urban or built-up land is any contiguous unit of land 10     crops and rate the soils according to the limitations
acres or more in size that is used for such purposes         that affect various aspects of forestland management.
128                                                                                                     Soil Survey of




Forestland Productivity                                     of individual limitations. The ratings are shown as
                                                            decimal fractions ranging from 0.01 to 1.00. They
   In table 8, the potential productivity of merchantable   indicate gradations between the point at which a soil
or common trees on a soil is expressed as a site index      feature has the greatest negative impact on the
and as a volume number. The site index is the average       specified forestland management practice (1.00) and
height, in feet, that dominant and codominant trees of      the point at which the soil feature is not a limitation
a given species attain in a specified number of years.      (0.00).
The site index applies to fully stocked, even-aged,             Rating class terms for seedling mortality are
unmanaged stands. Commonly grown trees are those            expressed as low, moderate, and high. Where these
that forest managers generally favor in intermediate or     terms are used, the numerical ratings indicate
improvement cuttings. They are selected on the basis        gradations between the point at which the potential for
of growth rate, quality, value, and marketability. More     seedling mortality is highest (1.00) and the point at
detailed information regarding site index is available in   which the potential is lowest (0.00).
the “National Forestry Manual,” which is available in           The paragraphs that follow indicate the soil
local offices of the Natural Resources Conservation         properties considered in rating the soils for forestland
Service or on the Internet.                                 management practices. More detailed information
   The volume of wood fiber, a number, is the yield         about the criteria used in the ratings is available in the
likely to be produced by the most important tree            “National Forestry Manual,” which is available in local
species. This number, expressed as cubic feet per           offices of the Natural Resources Conservation Service
acre per year and calculated at the age of culmination      or on the Internet.
of the mean annual increment (CMAI), indicates the              For limitations affecting construction of haul roads
amount of fiber produced in a fully stocked, even-          and log landings, the ratings are based on slope,
aged, unmanaged stand.                                      flooding, permafrost, plasticity index, the hazard of soil
   Trees to manage are those that are preferred for         slippage, content of sand, the Unified classification,
planting, seeding, or natural regeneration and those        rock fragments on or below the surface, depth to a
that remain in the stand after thinning or partial          restrictive layer that is indurated, depth to a water
harvest.                                                    table, and ponding. The limitations are described as
                                                            slight, moderate, or severe. A rating of slight indicates
Forestland Management                                       that no significant limitations affect construction
                                                            activities, moderate indicates that one or more
   In tables 9a, 9b, 9c, 9d, and 9e, interpretive ratings   limitations can cause some difficulty in construction,
are given for various aspects of forestland management.     and severe indicates that one or more limitations can
The ratings are both verbal and numerical.                  make construction very difficult or very costly.
   Some rating class terms indicate the degree to               The ratings of suitability for log landings are based
which the soils are suited to a specified forestland        on slope, rock fragments on the surface, plasticity
management practice. Well suited indicates that the         index, content of sand, the Unified classification, depth
soil has features that are favorable for the specified      to a water table, ponding, flooding, and the hazard of
practice and has no limitations. Good performance can       soil slippage. The soils are described as well suited,
be expected, and little or no maintenance is needed.        moderately suited, or poorly suited to use as log
Moderately suited indicates that the soil has features      landings.
that are moderately favorable for the specified practice.       Ratings in the column soil rutting hazard are based
One or more soil properties are less than desirable,        on depth to a water table, rock fragments on or below
and fair performance can be expected. Some                  the surface, the Unified classification, depth to a
maintenance is needed. Poorly suited indicates that         restrictive layer, and slope. Ruts form as a result of the
the soil has one or more properties that are                operation of forest equipment. The hazard is described
unfavorable for the specified practice. Overcoming the      as slight, moderate, or severe. A rating of slight
unfavorable properties requires special design, extra       indicates that the soil is subject to little or no rutting,
maintenance, and costly alteration. Unsuited indicates      moderate indicates that rutting is likely, and severe
that the expected performance of the soil is                indicates that ruts form readily.
unacceptable for the specified practice or that extreme         Ratings in the column hazard of off-road or off-trail
measures are needed to overcome the undesirable             erosion are based on slope and on soil erodibility
soil properties.                                            factor K. The soil loss is caused by sheet or rill erosion
   Numerical ratings in the tables indicate the severity    in off-road or off-trail areas where 50 to 75 percent of
Rock Island County, Illinois                                                                                        129




the surface has been exposed by logging, grazing,            below the surface, depth to a water table, and ponding.
mining, or other kinds of disturbance. The hazard is         The soils are described as well suited, poorly suited,
described as slight, moderate, severe, or very severe.       or unsuited to this management activity. The part of
A rating of slight indicates that erosion is unlikely        the soil from the surface to a depth of about 1 foot is
under ordinary climatic conditions; moderate indicates       considered in the ratings.
that some erosion is likely and that erosion-control            Ratings in the column suitability for mechanical site
measures may be needed; severe indicates that                preparation (deep) are based on slope, depth to a
erosion is very likely and that erosion-control              restrictive layer, rock fragments on or below the
measures, including revegetation of bare areas, are          surface, depth to a water table, and ponding. The soils
advised; and very severe indicates that significant          are described as well suited, poorly suited, or unsuited
erosion is expected, loss of soil productivity and off-      to this management activity. The part of the soil from
site damage are likely, and erosion-control measures         the surface to a depth of about 3 feet is considered in
are costly and generally impractical.                        the ratings.
   Ratings in the column hazard of erosion on roads             Ratings in the column potential for seedling
and trails are based on the soil erodibility factor K,       mortality are based on flooding, ponding, depth to a
slope, and content of rock fragments. The ratings            water table, content of lime, reaction, salinity, available
apply to unsurfaced roads and trails. The hazard is          water capacity, soil moisture regime, soil temperature
described as slight, moderate, or severe. A rating of        regime, aspect, and slope. The soils are described as
slight indicates that little or no erosion is likely;        having a low, moderate, or high potential for seedling
moderate indicates that some erosion is likely, that the     mortality.
roads or trails may require occasional maintenance,
and that simple erosion-control measures are needed;
and severe indicates that significant erosion is             Windbreaks and Environmental
expected, that the roads or trails require frequent          Plantings
maintenance, and that costly erosion-control
measures are needed.                                            Windbreaks protect livestock, buildings, yards, fruit
   Ratings in the column suitability for roads (natural      trees, gardens, and cropland from wind and snow;
surface) are based on slope, rock fragments on the           help to keep snow on fields; and provide food and
surface, plasticity index, content of sand, the Unified      cover for wildlife. Field windbreaks are narrow
classification, depth to a water table, ponding, flooding,   plantings made at right angles to the prevailing wind
and the hazard of soil slippage. The ratings indicate        and at specific intervals across the field. The interval
the suitability for using the natural surface of the soil    depends on the erodibility of the soil.
for roads. The soils are described as well suited,              Environmental plantings help to beautify and screen
moderately suited, or poorly suited to this use.             houses and other buildings and to abate noise. The
   Ratings in the columns suitability for hand planting      plants, mostly evergreen shrubs and trees, are closely
and suitability for mechanical planting are based on         spaced. To ensure plant survival, a healthy planting
slope, depth to a restrictive layer, content of sand,        stock of suitable species should be planted properly
plasticity index, rock fragments on or below the             on a well prepared site and maintained in good
surface, depth to a water table, and ponding. The soils      condition.
are described as well suited, moderately suited, poorly         Table 10 shows the height that locally grown trees
suited, or unsuited to these methods of planting. It is      and shrubs are expected to reach in 20 years on
assumed that necessary site preparation is completed         various soils. The estimates in table 10 are based on
before seedlings are planted.                                measurements and observation of established
   Ratings in the column suitability for use of              plantings that have been given adequate care. They
harvesting equipment are based on slope, rock                can be used as a guide in planning windbreaks and
fragments on the surface, plasticity index, content of       screens. Additional information on planning
sand, the Unified classification, depth to a water table,    windbreaks and screens and planting and caring for
and ponding. The soils are described as well suited,         trees and shrubs can be obtained from the local office
moderately suited, or poorly suited to this use.             of the Natural Resources Conservation Service or of
   Ratings in the column suitability for mechanical site     the Cooperative Extension Service or from a
preparation (surface) are based on slope, depth to a         commercial nursery.
restrictive layer, plasticity index, rock fragments on or
130                                                                                                       Soil Survey of




Recreation                                                    areas are subject to heavy foot traffic and some
                                                              vehicular traffic. The ratings are based on the soil
    The soils of the survey area are rated in tables 11a      properties that affect the ease of developing camp
and 11b according to limitations that affect their            areas and the performance of the areas after
suitability for recreation. The ratings are both verbal       development. Slope, stoniness, and depth to bedrock
and numerical. Rating class terms indicate the extent         or a cemented pan are the main concerns affecting
to which the soils are limited by all of the soil features    the development of camp areas. The soil properties
that affect the recreational uses. Not limited indicates      that affect the performance of the areas after
that the soil has features that are very favorable for the    development are those that influence trafficability and
specified use. Good performance and very low                  promote the growth of vegetation, especially in heavily
maintenance can be expected. Somewhat limited                 used areas. For good trafficability, the surface of camp
indicates that the soil has features that are moderately      areas should absorb rainfall readily, remain firm under
favorable for the specified use. The limitations can be       heavy foot traffic, and not be dusty when dry. The soil
overcome or minimized by special planning, design, or         properties that influence trafficability are texture of the
installation. Fair performance and moderate                   surface layer, depth to a water table, ponding, flooding,
maintenance can be expected. Very limited indicates           permeability, and large stones. The soil properties that
that the soil has one or more features that are               affect the growth of plants are depth to bedrock or a
unfavorable for the specified use. The limitations            cemented pan, permeability, and toxic substances in
generally cannot be overcome without major soil               the soil.
reclamation, special design, or expensive installation           Picnic areas are subject to heavy foot traffic. Most
procedures. Poor performance and high maintenance             vehicular traffic is confined to access roads and
can be expected.                                              parking areas. The ratings are based on the soil
    Numerical ratings in the tables indicate the severity     properties that affect the ease of developing picnic
of individual limitations. The ratings are shown as           areas and that influence trafficability and the growth of
decimal fractions ranging from 0.01 to 1.00. They             vegetation after development. Slope and stoniness are
indicate gradations between the point at which a soil         the main concerns affecting the development of picnic
feature has the greatest negative impact on the use           areas. For good trafficability, the surface of picnic
(1.00) and the point at which the soil feature is not a       areas should absorb rainfall readily, remain firm under
limitation (0.00).                                            heavy foot traffic, and not be dusty when dry. The soil
    The ratings in the tables are based on restrictive        properties that influence trafficability are texture of the
soil features, such as wetness, slope, and texture of         surface layer, depth to a water table, ponding, flooding,
the surface layer. Susceptibility to flooding is              permeability, and large stones. The soil properties that
considered. Not considered in the ratings, but                affect the growth of plants are depth to bedrock or a
important in evaluating a site, are the location and          cemented pan, permeability, and toxic substances in
accessibility of the area, the size and shape of the          the soil.
area and its scenic quality, vegetation, access to               Playgrounds require soils that are nearly level, are
water, potential water impoundment sites, and access          free of stones, and can withstand intensive foot traffic.
to public sewer lines. The capacity of the soil to absorb     The ratings are based on the soil properties that affect
septic tank effluent and the ability of the soil to support   the ease of developing playgrounds and that influence
vegetation also are important. Soils that are subject to      trafficability and the growth of vegetation after
flooding are limited for recreational uses by the             development. Slope and stoniness are the main
duration and intensity of flooding and the season when        concerns affecting the development of playgrounds.
flooding occurs. In planning recreational facilities,         For good trafficability, the surface of the playgrounds
onsite assessment of the height, duration, intensity,         should absorb rainfall readily, remain firm under heavy
and frequency of flooding is essential.                       foot traffic, and not be dusty when dry. The soil
    The information in tables 11a and 11b can be              properties that influence trafficability are texture of the
supplemented by other information in this survey, for         surface layer, depth to a water table, ponding, flooding,
example, interpretations for building site development,       permeability, and large stones. The soil properties that
construction materials, sanitary facilities, and water        affect the growth of plants are depth to bedrock or a
management.                                                   cemented pan, permeability, and toxic substances in
    Camp areas require site preparation, such as              the soil.
shaping and leveling the tent and parking areas,                 Paths and trails for hiking and horseback riding
stabilizing roads and intensively used areas, and             should require little or no slope modification through
installing sanitary facilities and utility lines. Camp        cutting and filling. The ratings are based on the soil
Rock Island County, Illinois                                                                                        131




properties that affect trafficability and erodibility. These   established, improved, or maintained in most places.
properties are stoniness, depth to a water table,              Moderately intensive management is required for
ponding, flooding, slope, and texture of the surface           satisfactory results. A rating of poor indicates that
layer.                                                         limitations are severe for the designated element or
   Off-road motorcycle trails require little or no site        kind of habitat. Habitat can be created, improved, or
preparation. They are not covered with surfacing               maintained in most places, but management is difficult
material or vegetation. Considerable compaction of the         and must be intensive. A rating of very poor indicates
soil material is likely. The ratings are based on the soil     that restrictions for the element or kind of habitat are
properties that influence erodibility, trafficability,         very severe and that unsatisfactory results can be
dustiness, and the ease of revegetation. These                 expected. Creating, improving, or maintaining habitat
properties are stoniness, slope, depth to a water table,       is impractical or impossible.
ponding, flooding, and texture of the surface layer.               The elements of wildlife habitat are described in the
   Golf fairways are subject to heavy foot traffic and         following paragraphs.
some light vehicular traffic. Cutting or filling may be            Grain and seed crops are domestic grains and
required. Irrigation is not considered in the ratings. The     seed-producing herbaceous plants. Soil properties
ratings are based on the soil properties that affect           and features that affect the growth of grain and seed
plant growth and trafficability after vegetation is            crops are depth of the root zone, texture of the surface
established. The properties that affect plant growth are       layer, available water capacity, wetness, slope, surface
reaction; depth to a water table; ponding; depth to            stoniness, and flooding. Soil temperature and soil
bedrock or a cemented pan; the available water                 moisture also are considerations. Examples of grain
capacity in the upper 40 inches; the content of salts,         and seed crops are corn, soybeans, wheat, oats, and
sodium, or calcium carbonate; and sulfidic materials.          barley.
The properties that affect trafficability are flooding,            Grasses and legumes are domestic perennial
depth to a water table, ponding, slope, stoniness, and         grasses and herbaceous legumes. Soil properties and
the amount of sand, clay, or organic matter in the             features that affect the growth of grasses and legumes
surface layer. The suitability of the soil for traps, tees,    are depth of the root zone, texture of the surface layer,
roughs, and greens is not considered in the ratings.           available water capacity, wetness, surface stoniness,
                                                               flooding, and slope. Soil temperature and soil moisture
Wildlife Habitat                                               also are considerations. Examples of grasses and
                                                               legumes are bromegrass, timothy, orchardgrass,
    Soils affect the kind and amount of vegetation that        clover, alfalfa, wheatgrass, and birdsfoot trefoil.
is available to wildlife as food and cover. They also              Wild herbaceous plants are native or naturally
affect the construction of water impoundments. The             established grasses and forbs, including weeds. Soil
kind and abundance of wildlife depend largely on the           properties and features that affect the growth of these
amount and distribution of food, cover, and water.             plants are depth of the root zone, texture of the
Wildlife habitat can be created or improved by planting        surface layer, available water capacity, wetness,
appropriate vegetation, by maintaining the existing            surface stoniness, and flooding. Soil temperature and
plant cover, or by promoting the natural establishment         soil moisture also are considerations. Examples of wild
of desirable plants.                                           herbaceous plants are bluestems, indiangrass,
    In table 12, the soils in the survey area are rated        blueberry, goldenrod, dandelions, blackberry, ragweed,
according to their potential for providing habitat for         wheatgrass, and nightshade.
various kinds of wildlife. This information can be used            Hardwood trees and woody understory produce
in planning parks, wildlife refuges, nature study areas,       nuts or other fruit, buds, catkins, twigs, bark, and
and other developments for wildlife; in selecting soils        foliage. Soil properties and features that affect the
that are suitable for establishing, improving, or              growth of hardwood trees and shrubs are depth of the
maintaining specific elements of wildlife habitat; and in      root zone, available water capacity, and wetness.
determining the intensity of management needed for             Examples of these plants are oak, poplar, cherry,
each element of the habitat.                                   birch, maple, green ash, willow, and American elm.
    The potential of the soil is rated good, fair, poor, or        Coniferous plants furnish browse and seeds. Soil
very poor. A rating of good indicates that the element         properties and features that affect the growth of
or kind of habitat is easily established, improved, or         coniferous trees, shrubs, and ground cover are depth
maintained. Few or no limitations affect management,           of the root zone, available water capacity, and
and satisfactory results can be expected. A rating of          wetness. Examples of coniferous plants are pine,
fair indicates that the element or kind of habitat can be      spruce, fir, cedar, and tamarack.
132                                                                                                    Soil Survey of




    Wetland plants are annual and perennial wild             ecological wetland plant species. Hydric soils that
herbaceous plants that grow on moist or wet sites.           have been converted to other uses should be capable
Submerged or floating aquatic plants are excluded.           of being restored to wetlands.
Soil properties and features affecting wetland plants           Hydric soils are defined by the National Technical
are texture of the surface layer, wetness, reaction,         Committee for Hydric Soils (NTCHS) as soils that
salinity, slope, and surface stoniness. Examples of          formed under conditions of saturation, flooding, or
wetland plants are smartweed, wild millet, rushes,           ponding long enough during the growing season to
sedges, bulrushes, wild rice, arrowhead,                     develop anaerobic conditions in the upper part
waterplantain, cattail, prairie cordgrass, bluejoint         (Federal Register, 1994). These soils are either
grass, asters, and beggarticks.                              saturated or inundated long enough during the
    Shallow water areas have an average depth of less        growing season to support the growth and
than 5 feet. Some are naturally wet areas. Others are        reproduction of hydrophytic vegetation.
created by dams, levees, or other water-control                 The NTCHS definition identifies general soil
structures. Soil properties and features affecting           properties that are associated with wetness. In order
shallow water areas are depth to bedrock, wetness,           to determine whether a specific soil is a hydric soil or
surface stoniness, slope, and permeability. Examples         nonhydric soil, however, more specific information,
of shallow water areas are marshes, waterfowl feeding        such as information about the depth and duration of
areas, wildlife watering developments, beaver ponds,         the water table, is needed. Thus, criteria that identify
and other wildlife ponds.                                    those estimated soil properties unique to hydric soils
    The habitat for various kinds of wildlife is described   have been established (Federal Register, 1995). These
in the following paragraphs.                                 criteria are used to identify a phase of a soil series
    Habitat for openland wildlife consists of cropland,      that normally is associated with wetlands. The criteria
pasture, meadows, and areas that are overgrown with          used are selected estimated soil properties that are
grasses, herbs, shrubs, and vines. These areas               described in “Soil Taxonomy” (Soil Survey Staff, 1999)
produce grain and seed crops, grasses and legumes,           and “Keys to Soil Taxonomy” (Soil Survey Staff, 1998)
and wild herbaceous plants. Wildlife attracted to these      and in the “Soil Survey Manual” (Soil Survey Division
areas include Hungarian partridge, ring-necked               Staff, 1993).
pheasant, bobwhite quail, sharp-tailed grouse,                  If soils are wet enough for a long enough period to
meadowlark, field sparrow, killdeer, cottontail rabbit,      be considered hydric, they should exhibit certain
and red fox.                                                 properties that can be easily observed in the field.
    Habitat for woodland wildlife consists of areas of       These visible properties are indicators of hydric soils.
deciduous and/or coniferous plants and associated            The indicators used to make onsite determinations of
grasses, legumes, and wild herbaceous plants. Wildlife       hydric soils in this survey area are specified in “Field
attracted to these areas include wild turkey, ruffed         Indicators of Hydric Soils in the United States” (Hurt
grouse, thrushes, woodpeckers, owls, tree squirrels,         and others, 1998).
porcupine, raccoon, deer, and bear.                             Hydric soils are identified by examining and
    Habitat for wetland wildlife consists of open, marshy    describing the soil to a depth of about 20 inches. This
or swampy shallow water areas. Some of the wildlife          depth may be greater if determination of an
attracted to such areas are ducks, geese, herons,            appropriate indicator so requires. It is always
shore birds, muskrat, mink, and beaver.                      recommended that soils be excavated and described
                                                             to the depth necessary for an understanding of the
Hydric Soils                                                 redoximorphic processes. Then, using the completed
                                                             soil descriptions, soil scientists can compare the soil
    In this section, hydric soils are defined and            features required by each indicator and specify which
described and the hydric soils in the survey area are        indicators have been matched with the conditions
listed.                                                      observed in the soil. The soil can be identified as a
    The three essential characteristics of wetlands are      hydric soil if at least one of the approved indicators is
hydrophytic vegetation, hydric soils, and wetland            present.
hydrology (Cowardin and others, 1979; U.S. Army                 Map units that are made up of hydric soils may
Corps of Engineers, 1987; National Research Council,         have small areas, or inclusions, of nonhydric soils in
1995; Tiner, 1985). Criteria for each of the                 the higher positions on the landform, and map units
characteristics must be met for areas to be identified       made up of nonhydric soils may have inclusions of
as wetlands. Undrained hydric soils that have natural        hydric soils in the lower positions on the landform.
vegetation should support a dominant population of              Table 13 identifies hydric soils in Rock Island
Rock Island County, Illinois                                                                                        133




County and also nonhydric soils that may have hydric           industrial, and recreational uses; make preliminary
inclusions. This information can help in planning land         estimates of construction conditions; evaluate
uses; however, onsite investigation is recommended to          alternative routes for roads, streets, highways,
determine whether hydric soils occur and the location          pipelines, and underground cables; evaluate
of the included hydric soils (National Research                alternative sites for sanitary landfills, septic tank
Council, 1995; Hurt and others, 1998).                         absorption fields, and sewage lagoons; plan detailed
                                                               onsite investigations of soils and geology; locate
Engineering                                                    potential sources of sand and topsoil; plan drainage
                                                               systems, irrigation systems, ponds, terraces, and
   This section provides information for planning land         other structures for soil and water conservation; and
uses related to urban development and to water                 predict performance of proposed small structures and
management. Soils are rated for various uses, and the          pavements by comparing the performance of existing
most limiting features are identified. Ratings are given       similar structures on the same or similar soils.
for building site development, sanitary facilities,               The information in the tables, along with the soil
construction materials, and water management. The              maps, the soil descriptions, and other data provided in
ratings are based on observed performance of the               this survey, can be used to make additional
soils and on the data in the tables described under the        interpretations.
heading “Soil Properties.”                                        Some of the terms used in this soil survey have a
   Information in this section is intended for land use        special meaning in soil science and are defined in the
planning, for evaluating land use alternatives, and for        Glossary.
planning site investigations prior to design and
construction. The information, however, has limitations.       Building Site Development
For example, estimates and other data generally apply
only to that part of the soil between the surface and a            Soil properties influence the development of
depth of 5 to 7 feet. Because of the map scale, small          building sites, including the selection of the site, the
areas of different soils may be included within the            design of the structure, construction, performance
mapped areas of a specific soil.                               after construction, and maintenance. Tables 14a and
   The information is not site specific and does not           14b show the degree and kind of soil limitations that
eliminate the need for onsite investigation of the soils       affect dwellings with and without basements, small
or for testing and analysis by personnel experienced in        commercial buildings, local roads and streets, shallow
the design and construction of engineering works.              excavations, and lawns and landscaping.
   Government ordinances and regulations that                      The ratings in the tables are both verbal and
restrict certain land uses or impose specific design           numerical. Rating class terms indicate the extent to
criteria were not considered in preparing the                  which the soils are limited by all of the soil features
information in this section. Local ordinances and              that affect building site development. Not limited
regulations should be considered in planning, in site          indicates that the soil has features that are very
selection, and in design.                                      favorable for the specified use. Good performance and
   Soil properties, site features, and observed                very low maintenance can be expected. Somewhat
performance were considered in determining the                 limited indicates that the soil has features that are
ratings in this section. During the fieldwork for this soil    moderately favorable for the specified use. The
survey, determinations were made about particle-size           limitations can be overcome or minimized by special
distribution, liquid limit, plasticity index, soil reaction,   planning, design, or installation. Fair performance and
depth to bedrock, hardness of bedrock within 5 to 7            moderate maintenance can be expected. Very limited
feet of the surface, soil wetness, depth to a water            indicates that the soil has one or more features that
table, ponding, slope, likelihood of flooding, natural soil    are unfavorable for the specified use. The limitations
structure aggregation, and soil density. Data were             generally cannot be overcome without major soil
collected about kinds of clay minerals, mineralogy of          reclamation, special design, or expensive installation
the sand and silt fractions, and the kinds of adsorbed         procedures. Poor performance and high maintenance
cations. Estimates were made for erodibility,                  can be expected.
permeability, corrosivity, shrink-swell potential,                 Numerical ratings in the tables indicate the severity
available water capacity, and other behavioral                 of individual limitations. The ratings are shown as
characteristics affecting engineering uses.                    decimal fractions ranging from 0.01 to 1.00. They
   This information can be used to evaluate the                indicate gradations between the point at which a soil
potential of areas for residential, commercial,                feature has the greatest negative impact on the use
134                                                                                                     Soil Survey of




(1.00) and the point at which the soil feature is not a     cemented pan, depth to a water table, ponding,
limitation (0.00).                                          flooding, the amount of large stones, and slope. The
   Dwellings are single-family houses of three stories      properties that affect the traffic-supporting capacity
or less. For dwellings without basements, the               are soil strength (as inferred from the AASHTO group
foundation is assumed to consist of spread footings of      index number), subsidence, linear extensibility (shrink-
reinforced concrete built on undisturbed soil at a depth    swell potential), the potential for frost action, depth to a
of 2 feet or at the depth of maximum frost penetration,     water table, and ponding.
whichever is deeper. For dwellings with basements,              Shallow excavations are trenches or holes dug to a
the foundation is assumed to consist of spread              maximum depth of 5 or 6 feet for graves, utility lines,
footings of reinforced concrete built on undisturbed soil   open ditches, or other purposes. The ratings are
at a depth of about 7 feet. The ratings for dwellings are   based on the soil properties that influence the ease of
based on the soil properties that affect the capacity of    digging and the resistance to sloughing. Depth to
the soil to support a load without movement and on          bedrock or a cemented pan, hardness of bedrock or a
the properties that affect excavation and construction      cemented pan, the amount of large stones, and dense
costs. The properties that affect the load-supporting       layers influence the ease of digging, filling, and
capacity include depth to a water table, ponding,           compacting. Depth to the seasonal high water table,
flooding, subsidence, linear extensibility (shrink-swell    flooding, and ponding may restrict the period when
potential), and compressibility. Compressibility is         excavations can be made. Slope influences the ease
inferred from the Unified classification. The properties    of using machinery. Soil texture, depth to the water
that affect the ease and amount of excavation include       table, and linear extensibility (shrink-swell potential)
depth to a water table, ponding, flooding, slope, depth     influence the resistance to sloughing.
to bedrock or a cemented pan, hardness of bedrock or            Lawns and landscaping require soils on which turf
a cemented pan, and the amount and size of rock             and ornamental trees and shrubs can be established
fragments.                                                  and maintained. Irrigation is not considered in the
   Small commercial buildings are structures that are       ratings. The ratings are based on the soil properties
less than three stories high and do not have                that affect plant growth and trafficability after
basements. The foundation is assumed to consist of          vegetation is established. The properties that affect
spread footings of reinforced concrete built on             plant growth are reaction; depth to a water table;
undisturbed soil at a depth of 2 feet or at the depth of    ponding; depth to bedrock or a cemented pan; the
maximum frost penetration, whichever is deeper. The         available water capacity in the upper 40 inches; the
ratings are based on the soil properties that affect the    content of salts, sodium, or calcium carbonate; and
capacity of the soil to support a load without              sulfidic materials. The properties that affect
movement and on the properties that affect excavation       trafficability are flooding, depth to a water table,
and construction costs. The properties that affect the      ponding, slope, stoniness, and the amount of sand,
load-supporting capacity include depth to a water           clay, or organic matter in the surface layer.
table, ponding, flooding, subsidence, linear
extensibility (shrink-swell potential), and                 Sanitary Facilities
compressibility (which is inferred from the Unified
classification). The properties that affect the ease and       Table 15 shows the degree and kind of soil
amount of excavation include flooding, depth to a           limitations that affect septic tank absorption fields,
water table, ponding, slope, depth to bedrock or a          sewage lagoons, sanitary landfills, and daily cover for
cemented pan, hardness of bedrock or a cemented             landfill. The ratings are both verbal and numerical.
pan, and the amount and size of rock fragments.             Rating class terms indicate the extent to which the
   Local roads and streets have an all-weather surface      soils are limited by all of the soil features that affect
and carry automobile and light truck traffic all year.      these uses. Not limited indicates that the soil has
They have a subgrade of cut or fill soil material; a base   features that are very favorable for the specified use.
of gravel, crushed rock, or soil material stabilized by     Good performance and very low maintenance can be
lime or cement; and a surface of flexible material          expected. Somewhat limited indicates that the soil has
(asphalt), rigid material (concrete), or gravel with a      features that are moderately favorable for the specified
binder. The ratings are based on the soil properties        use. The limitations can be overcome or minimized by
that affect the ease of excavation and grading and the      special planning, design, or installation. Fair
traffic-supporting capacity. The properties that affect     performance and moderate maintenance can be
the ease of excavation and grading are depth to             expected. Very limited indicates that the soil has one
bedrock or a cemented pan, hardness of bedrock or a         or more features that are unfavorable for the specified
Rock Island County, Illinois                                                                                        135




use. The limitations generally cannot be overcome            table is high enough to raise the level of sewage in the
without major soil reclamation, special design, or           lagoon, or if floodwater overtops the lagoon.
expensive installation procedures. Poor performance              A high content of organic matter is detrimental to
and high maintenance can be expected.                        proper functioning of the lagoon because it inhibits
    Numerical ratings in the table indicate the severity     aerobic activity. Slope, bedrock, and cemented pans
of individual limitations. The ratings are shown as          can cause construction problems, and large stones
decimal fractions ranging from 0.01 to 1.00. They            can hinder compaction of the lagoon floor. If the
indicate gradations between the point at which a soil        lagoon is to be uniformly deep throughout, the slope
feature has the greatest negative impact on the use          must be gentle enough and the soil material must be
(1.00) and the point at which the soil feature is not a      thick enough over bedrock or a cemented pan to make
limitation (0.00).                                           land smoothing practical.
    Septic tank absorption fields are areas in which             A trench sanitary landfill is an area where solid
effluent from a septic tank is distributed into the soil     waste is placed in successive layers in an excavated
through subsurface tiles or perforated pipe. Only that       trench. The waste is spread, compacted, and covered
part of the soil between depths of 24 and 60 inches is       daily with a thin layer of soil excavated at the site.
evaluated. The ratings are based on the soil properties      When the trench is full, a final cover of soil material at
that affect absorption of the effluent, construction and     least 2 feet thick is placed over the landfill. The ratings
maintenance of the system, and public health.                in the table are based on the soil properties that affect
Permeability, depth to a water table, ponding, depth to      the risk of pollution, the ease of excavation,
bedrock or a cemented pan, and flooding affect               trafficability, and revegetation. These properties
absorption of the effluent. Stones and boulders, ice,        include permeability, depth to bedrock or a cemented
and bedrock or a cemented pan interfere with                 pan, depth to a water table, ponding, slope, flooding,
installation. Subsidence interferes with installation and    texture, stones and boulders, highly organic layers,
maintenance. Excessive slope may cause lateral               soil reaction, and content of salts and sodium. Unless
seepage and surfacing of the effluent in downslope           otherwise stated, the ratings apply only to that part of
areas.                                                       the soil within a depth of about 6 feet. For deeper
    Some soils are underlain by loose sand and gravel        trenches, onsite investigation may be needed.
or fractured bedrock at a depth of less than 4 feet              Hard, nonrippable bedrock, creviced bedrock, or
below the distribution lines. In these soils the             highly permeable strata in or directly below the
absorption field may not adequately filter the effluent,     proposed trench bottom can affect the ease of
particularly when the system is new. As a result, the        excavation and the hazard of ground-water pollution.
ground water may become contaminated.                        Slope affects construction of the trenches and the
    Sewage lagoons are shallow ponds constructed to          movement of surface water around the landfill. It also
hold sewage while aerobic bacteria decompose the             affects the construction and performance of roads in
solid and liquid wastes. Lagoons should have a nearly        areas of the landfill.
level floor surrounded by cut slopes or embankments              Soil texture and consistence affect the ease with
of compacted soil. Nearly impervious soil material for       which the trench is dug and the ease with which the
the lagoon floor and sides is required to minimize           soil can be used as daily or final cover. They
seepage and contamination of ground water.                   determine the workability of the soil when dry and
Considered in the ratings are slope, permeability,           when wet. Soils that are plastic and sticky when wet
depth to a water table, ponding, depth to bedrock or a       are difficult to excavate, grade, or compact and are
cemented pan, flooding, large stones, and content of         difficult to place as a uniformly thick cover over a layer
organic matter.                                              of refuse.
    Soil permeability is a critical property affecting the       The soil material used as the final cover for a trench
suitability for sewage lagoons. Most porous soils            landfill should be suitable for plants. It should not have
eventually become sealed when they are used as sites         excess sodium or salts and should not be too acid.
for sewage lagoons. Until sealing occurs, however, the       The surface layer generally has the best workability,
hazard of pollution is severe. Soils that have a             the highest content of organic matter, and the best
permeability rate of more than 2 inches per hour are         potential for plants. Material from the surface layer
too porous for the proper functioning of sewage              should be stockpiled for use as the final cover.
lagoons. In these soils, seepage of the effluent can             In an area sanitary landfill, solid waste is placed in
result in contamination of the ground water. Ground-         successive layers on the surface of the soil. The waste
water contamination is also a hazard if fractured            is spread, compacted, and covered daily with a thin
bedrock is within a depth of 40 inches, if the water         layer of soil from a source away from the site. A final
136                                                                                                      Soil Survey of




cover of soil material at least 2 feet thick is placed over   Rock Island County are poor sources of gravel, this
the completed landfill. The ratings in the table are          interpretation is not included in table 16. In the table,
based on the soil properties that affect trafficability and   only the likelihood of finding material in suitable
the risk of pollution. These properties include flooding,     quantity is evaluated. The suitability of the material for
permeability, depth to a water table, ponding, slope,         specific purposes is not evaluated, nor are factors that
and depth to bedrock or a cemented pan.                       affect excavation of the material. The properties used
    Flooding is a serious problem because it can result       to evaluate the soil as a source of sand are gradation
in pollution in areas downstream from the landfill. If        of grain sizes (as indicated by the Unified classification
permeability is too rapid or if fractured bedrock, a          of the soil), the thickness of suitable material, and the
fractured cemented pan, or the water table is close to        content of rock fragments. If the bottom layer of the
the surface, the leachate can contaminate the water           soil contains sand, the soil is considered a likely
supply. Slope is a consideration because of the extra         source regardless of thickness. The assumption is that
grading required to maintain roads in the steeper             the sand layer below the depth of observation exceeds
areas of the landfill. Also, leachate may flow along the      the minimum thickness.
surface of the soils in the steeper areas and cause              The soils are rated good, fair, or poor as potential
difficult seepage problems.                                   sources of sand. A rating of good or fair means that
    Daily cover for landfill is the soil material that is     the source material is likely to be in or below the soil.
used to cover compacted solid waste in an area                The bottom layer and the thickest layer of the soils are
sanitary landfill. The soil material is obtained offsite,     assigned numerical ratings. These ratings indicate the
transported to the landfill, and spread over the waste.       likelihood that the layer is a source of sand. The
The ratings in the table also apply to the final cover for    number 0.00 indicates that the layer is a poor source.
a landfill. They are based on the soil properties that        The number 1.00 indicates that the layer is a good
affect workability, the ease of digging, and the ease of      source. A number between 0.00 and 1.00 indicates the
moving and spreading the material over the refuse             degree to which the layer is a likely source.
daily during wet and dry periods. These properties               The soils are rated good, fair, or poor as potential
include soil texture, depth to a water table, ponding,        sources of topsoil, reclamation material, and roadfill.
rock fragments, slope, depth to bedrock or a cemented         The features that limit the soils as sources of these
pan, reaction, and content of salts, sodium, or lime.         materials are specified in the table. The numerical
    Loamy or silty soils that are free of large stones and    ratings given after the specified features indicate the
excess gravel are the best cover for a landfill. Clayey       degree to which the features limit the soils as sources
soils may be sticky and difficult to spread; sandy soils      of topsoil, reclamation material, or roadfill. The lower
are subject to wind erosion.                                  the number, the greater the limitation.
    Slope affects the ease of excavation and of moving           Topsoil is used to cover an area so that vegetation
the cover material. Also, it can influence runoff,            can be established and maintained. The upper 40
erosion, and reclamation of the borrow area.                  inches of a soil is evaluated for use as topsoil. Also
    After soil material has been removed, the soil            evaluated is the reclamation potential of the borrow
material remaining in the borrow area must be thick           area. The ratings are based on the soil properties that
enough over bedrock, a cemented pan, or the water             affect plant growth; the ease of excavating, loading,
table to permit revegetation. The soil material used as       and spreading the material; and reclamation of the
the final cover for a landfill should be suitable for         borrow area. Toxic substances, soil reaction, and the
plants. It should not have excess sodium, salts, or lime      properties that are inferred from soil texture, such as
and should not be too acid.                                   available water capacity and fertility, affect plant
                                                              growth. The ease of excavating, loading, and
Construction Materials                                        spreading is affected by rock fragments, slope, depth
                                                              to a water table, soil texture, and thickness of suitable
   Table 16 gives information about the soils as              material. Reclamation of the borrow area is affected by
potential sources of sand, topsoil, reclamation               slope, depth to a water table, rock fragments, depth to
material, and roadfill. Normal compaction, minor              bedrock or a cemented pan, and toxic material.
processing, and other standard construction practices            The surface layer of most soils is generally
are assumed.                                                  preferred for topsoil because of its organic matter
   Sand and gravel are natural aggregates suitable for        content. Organic matter greatly increases the
commercial use with a minimum of processing. They             absorption and retention of moisture and nutrients for
are used in many kinds of construction. Specifications        plant growth.
for each use vary widely. Because all of the soils in            Reclamation material is used in areas that have
Rock Island County, Illinois                                                                                       137




been drastically disturbed by surface mining or similar      favorable for the specified use. The limitations can be
activities. When these areas are reclaimed, layers of        overcome or minimized by special planning, design, or
soil material or unconsolidated geological material, or      installation. Fair performance and moderate
both, are replaced in a vertical sequence. The               maintenance can be expected. Very limited indicates
reconstructed soil favors plant growth. The ratings in       that the soil has one or more features that are
the table do not apply to quarries and other mined           unfavorable for the specified use. The limitations
areas that require an offsite source of reconstruction       generally cannot be overcome without major soil
material. The ratings are based on the soil properties       reclamation, special design, or expensive installation
that affect erosion and stability of the surface and the     procedures. Poor performance and high maintenance
productive potential of the reconstructed soil. These        can be expected.
properties include the content of sodium, salts, and             Numerical ratings in the tables indicate the severity
calcium carbonate; reaction; available water capacity;       of individual limitations. The ratings are shown as
erodibility; texture; content of rock fragments; and         decimal fractions ranging from 0.01 to 1.00. They
content of organic matter and other features that affect     indicate gradations between the point at which a soil
fertility.                                                   feature has the greatest negative impact on the use
    Roadfill is soil material that is excavated in one       (1.00) and the point at which the soil feature is not a
place and used in road embankments in another                limitation (0.00).
place. In this table, the soils are rated as a source of         Pond reservoir areas hold water behind a dam or
roadfill for low embankments, generally less than 6          embankment. Soils best suited to this use have low
feet high and less exacting in design than higher            seepage potential in the upper 60 inches. The
embankments.                                                 seepage potential is determined by the permeability of
    The ratings are for the whole soil, from the surface     the soil and the depth to fractured bedrock or other
to a depth of about 5 feet. It is assumed that soil layers   permeable material. Excessive slope can affect the
will be mixed when the soil material is excavated and        storage capacity of the reservoir area.
spread.                                                          Embankments, dikes, and levees are raised
    The ratings are based on the amount of suitable          structures of soil material, generally less than 20 feet
material and on soil properties that affect the ease of      high, constructed to impound water or to protect land
excavation and the performance of the material after it      against overflow. Embankments that have zoned
is in place. The thickness of the suitable material is a     construction (core and shell) are not considered. In
major consideration. The ease of excavation is               this table, the soils are rated as a source of material
affected by large stones, depth to a water table, and        for embankment fill. The ratings apply to the soil
slope. How well the soil performs in place after it has      material below the surface layer to a depth of about 5
been compacted and drained is determined by its              feet. It is assumed that soil layers will be uniformly
strength (as inferred from the AASHTO classification         mixed and compacted during construction.
of the soil) and linear extensibility (shrink-swell              The ratings do not indicate the ability of the natural
potential).                                                  soil to support an embankment. Soil properties to a
                                                             depth even greater than the height of the embankment
Water Management                                             can affect performance and safety of the embankment.
                                                             Generally, deeper onsite investigation is needed to
   Tables 17a and 17b give information on the soil           determine these properties.
properties and site features that affect water                   Soil material in embankments must be resistant to
management. The degree and kind of soil limitations          seepage, piping, and erosion and have favorable
are given for pond reservoir areas; embankments,             compaction characteristics. Unfavorable features
dikes, and levees; aquifer-fed excavated ponds;              include less than 5 feet of suitable material and a high
constructing grassed waterways and surface drains;           content of stones or boulders, organic matter, or salts
constructing terraces and diversions; and tile drains        or sodium. A high water table affects the amount of
and underground outlets. The ratings are both verbal         usable material. It also affects trafficability.
and numerical. Rating class terms indicate the extent            Aquifer-fed excavated ponds are pits or dugouts
to which the soils are limited by all of the soil features   that extend to a ground-water aquifer or to a depth
that affect these uses. Not limited indicates that the       below a permanent water table. Excluded are ponds
soil has features that are very favorable for the            that are fed only by surface runoff and embankment
specified use. Good performance and very low                 ponds that impound water 3 feet or more above the
maintenance can be expected. Somewhat limited                original surface. Excavated ponds are affected by
indicates that the soil has features that are moderately     depth to a permanent water table, permeability of the
138




aquifer, and quality of the water as inferred from the      terraces and diversions. A restricted rooting depth, a
salinity of the soil. Depth to bedrock and the content of   severe hazard of wind erosion or water erosion, an
large stones affect the ease of excavation.                 excessively coarse texture, and restricted permeability
   Grassed waterways and surface drains are natural         adversely affect maintenance.
or constructed channels, generally broad and shallow,          Tile drains and underground outlets are used in
that conduct surface water to outlets at a nonerosive       some areas to remove excess subsurface and surface
velocity. Large stones, wetness, slope, and depth to        water from the soil. The ratings in the table apply to the
bedrock affect the construction of grassed waterways        soil in its undisturbed condition and do not include
and surface drains. A hazard of wind erosion, a low         consideration of current land use. Depth to bedrock, a
available water capacity, restricted rooting depth, toxic   dense layer, or a cemented pan, the content of large
substances such as salts and sodium, and restricted         stones, and the content of clay influence the ease of
permeability adversely affect the growth and                digging, filling, and compacting. A seasonal high water
maintenance of the grass after construction.                table, ponding, and flooding may restrict the period
   Terraces and diversions are embankments or a             when excavations can be made. The slope influences
combination of channels and ridges constructed              the use of machinery. Soil texture and depth to the
across a slope to control erosion and conserve              water table influence the resistance to sloughing.
moisture by intercepting runoff. Slope, wetness, large      Subsidence of organic layers influences grade and
stones, and depth to bedrock affect the construction of     stability of tile drains.
                                                                                                                 139




Soil Properties
    Data relating to soil properties are collected during        The Unified system classifies soils according to
the course of the soil survey.                               properties that affect their use as construction
    Soil properties are ascertained by field examination     material. Soils are classified according to particle-size
of the soils and by laboratory index testing of some         distribution of the fraction less than 3 inches in
benchmark soils. Established standard procedures are         diameter and according to plasticity index, liquid limit,
followed. During the survey, many shallow borings are        and organic matter content. Sandy and gravelly soils
made and examined to identify and classify the soils         are identified as GW, GP, GM, GC, SW, SP, SM, and
and to delineate them on the soil maps. Samples are          SC; silty and clayey soils as ML, CL, OL, MH, CH, and
taken from some typical profiles and tested in the           OH; and highly organic soils as PT. Soils exhibiting
laboratory to determine particle-size distribution,          engineering properties of two groups can have a dual
plasticity, and compaction characteristics.                  classification, for example, CL-ML.
    Estimates of soil properties are based on field              The AASHTO system classifies soils according to
examinations, on laboratory tests of samples from the        those properties that affect roadway construction and
survey area, and on laboratory tests of samples of           maintenance. In this system, the fraction of a mineral
similar soils in nearby areas. Tests verify field            soil that is less than 3 inches in diameter is classified
observations, verify properties that cannot be               in one of seven groups from A-1 through A-7 on the
estimated accurately by field observation, and help to       basis of particle-size distribution, liquid limit, and
characterize key soils.                                      plasticity index. Soils in group A-1 are coarse grained
    The estimates of soil properties are shown in            and low in content of fines (silt and clay). At the other
tables. They include engineering index properties,           extreme, soils in group A-7 are fine grained. Highly
physical and chemical properties, and pertinent soil         organic soils are classified in group A-8 on the basis of
and water features.                                          visual inspection.
                                                                 If laboratory data are available, the A-1, A-2, and
Engineering Index Properties                                 A-7 groups are further classified as A-1-a, A-1-b,
                                                             A-2-4, A-2-5, A-2-6, A-2-7, A-7-5, or A-7-6. As an
    Table 18 gives the engineering classifications and       additional refinement, the suitability of a soil as
the range of index properties for the layers of each soil    subgrade material can be indicated by a group index
in the survey area.                                          number. Group index numbers range from 0 for the
    Depth to the upper and lower boundaries of each          best subgrade material to 20 or higher for the poorest.
layer is indicated.                                              Rock fragments larger than 10 inches in diameter
    Texture is given in the standard terms used by the       and 3 to 10 inches in diameter are indicated as a
U.S. Department of Agriculture. These terms are              percentage of the total soil on a dry-weight basis. The
defined according to percentages of sand, silt, and          percentages are estimates determined mainly by
clay in the fraction of the soil that is less than 2         converting volume percentage in the field to weight
millimeters in diameter. “Loam,” for example, is soil that   percentage.
is 7 to 27 percent clay, 28 to 50 percent silt, and less         Percentage (of soil particles) passing designated
than 52 percent sand. If the content of particles            sieves is the percentage of the soil fraction less than 3
coarser than sand is 15 percent or more, an                  inches in diameter based on an ovendry weight. The
appropriate modifier is added, for example, “gravelly.”      sieves, numbers 4, 10, 40, and 200 (USA Standard
Textural terms are defined in the Glossary.                  Series), have openings of 4.76, 2.00, 0.420, and 0.074
    Classification of the soils is determined according to   millimeters, respectively. Estimates are based on
the Unified soil classification system (ASTM, 2001)          laboratory tests of soils sampled in the survey area
and the system adopted by the American Association           and in nearby areas and on estimates made in the
of State Highway and Transportation Officials                field.
(AASHTO, 2000).                                                  Liquid limit and plasticity index (Atterberg limits)
140                                                                                                        Soil Survey of




indicate the plasticity characteristics of a soil. The         in soil surveys, indicates saturated hydraulic
estimates are based on test data from the survey area          conductivity (Ksat ). The estimates in the table indicate
or from nearby areas and on field examination.                 the rate of water movement, in inches per hour, when
   The estimates of particle-size distribution, liquid         the soil is saturated. They are based on soil
limit, and plasticity index are generally rounded to the       characteristics observed in the field, particularly
nearest 5 percent. Thus, if the ranges of gradation and        structure, porosity, and texture. Permeability is
Atterberg limits extend a marginal amount (1 or 2              considered in the design of soil drainage systems and
percentage points) across classification boundaries,           septic tank absorption fields.
the classification in the marginal zone is generally               Available water capacity refers to the quantity of
omitted in the table.                                          water that the soil is capable of storing for use by
                                                               plants. The capacity for water storage is given in
Physical Properties                                            inches of water per inch of soil for each soil layer. The
                                                               capacity varies, depending on soil properties that
     Table 19 shows estimates of some physical                 affect retention of water. The most important
characteristics and features that affect soil behavior.        properties are the content of organic matter, soil
These estimates are given for the layers of each soil in       texture, bulk density, and soil structure. Available water
the survey area. The estimates are based on field              capacity is an important factor in the choice of plants
observations and on test data for these and similar            or crops to be grown and in the design and
soils.                                                         management of irrigation systems. Available water
     Depth to the upper and lower boundaries of each           capacity is not an estimate of the quantity of water
layer is indicated.                                            actually available to plants at any given time.
     Clay as a soil separate consists of mineral soil              Linear extensibility refers to the change in length of
particles that are less than 0.002 millimeter in               an unconfined clod as moisture content is decreased
diameter. In the table, the estimated clay content of          from a moist to a dry state. It is an expression of the
each soil layer is given as a percentage, by weight, of        volume change between the water content of the clod
the soil material that is less than 2 millimeters in           at 1/3- or 1/10-bar tension (33kPa or 10kPa tension) and
diameter.                                                      oven dryness. The volume change is reported in the
     The amount and kind of clay affect the fertility and      table as percent change for the whole soil. Volume
physical condition of the soil and the ability of the soil     change is influenced by the amount and type of clay
to adsorb cations and to retain moisture. They                 minerals in the soil.
influence shrink-swell potential, permeability, plasticity,        Linear extensibility is used to determine the shrink-
the ease of soil dispersion, and other soil properties.        swell potential of soils. The shrink-swell potential is low
The amount and kind of clay in a soil also affect tillage      if the soil has a linear extensibility of less than 3
and earthmoving operations.                                    percent; moderate if 3 to 6 percent; high if 6 to 9
     Moist bulk density is the weight of soil (ovendry) per    percent; and very high if more than 9 percent. If the
unit volume. Volume is measured when the soil is at            linear extensibility is more than 3, shrinking and
field moisture capacity, that is, the moisture content at      swelling can cause damage to buildings, roads, and
1
  /3- or 1/10-bar (33kPa or 10kPa) moisture tension.           other structures and to plant roots. Special design
Weight is determined after the soil is dried at 105            commonly is needed.
degrees C. In the table, the estimated moist bulk                  Erosion factors are shown in table 19 as the K
density of each soil horizon is expressed in grams per         factor (Kw and Kf) and the T factor. Erosion factor K
cubic centimeter of soil material that is less than 2          indicates the susceptibility of a soil to sheet and rill
millimeters in diameter. Bulk density data are used to         erosion by water. Factor K is one of six factors used in
compute shrink-swell potential, available water                the Universal Soil Loss Equation (USLE) and the
capacity, total pore space, and other soil properties.         Revised Universal Soil Loss Equation (RUSLE) to
The moist bulk density of a soil indicates the pore            predict the average annual rate of soil loss by sheet
space available for water and roots. Depending on soil         and rill erosion in tons per acre per year. The
texture, a bulk density of more than 1.4 can restrict          estimates are based primarily on percentage of silt,
water storage and root penetration. Moist bulk density         sand, and organic matter and on soil structure and
is influenced by texture, kind of clay, content of organic     permeability. Values of K range from 0.02 to 0.69.
matter, and soil structure.                                    Other factors being equal, the higher the value, the
     Permeability (Ksat ) refers to the ability of a soil to   more susceptible the soil is to sheet and rill erosion by
transmit water or air. The term “permeability,” as used        water.
Rock Island County, Illinois                                                                                        141




   Erosion factor Kw indicates the erodibility of the         capacity, water infiltration, soil organism activity, and
whole soil. The estimates are modified by the                 tilth. It is a source of nitrogen and other nutrients for
presence of rock fragments.                                   crops and soil organisms.
   Erosion factor Kf indicates the erodibility of the fine-       Cation-exchange capacity is the total amount of
earth fraction, or the material less than 2 millimeters in    extractable bases that can be held by the soil,
size.                                                         expressed in terms of milliequivalents per 100 grams
   Erosion factor T is an estimate of the maximum             of soil at neutrality (pH 7.0) or at some other stated pH
average annual rate of soil erosion by wind or water          value. Soils having a low cation-exchange capacity
that can occur without affecting crop productivity over       hold fewer cations and may require more frequent
a sustained period. The rate is in tons per acre per          applications of fertilizer than soils having a high cation-
year.                                                         exchange capacity. The ability to retain cations
   Wind erodibility groups are made up of soils that          reduces the hazard of ground-water pollution.
have similar properties affecting their susceptibility to         Calcium carbonate equivalent is the percent of
wind erosion in cultivated areas. The soils assigned to       carbonates, by weight, in the fraction of the soil less
group 1 are the most susceptible to wind erosion, and         than 2 millimeters in size. The availability of plant
those assigned to group 8 are the least susceptible.          nutrients is influenced by the amount of carbonates in
Descriptions of these groups are available in the             the soil. Incorporating nitrogen fertilizer into calcareous
“National Soil Survey Handbook” (USDA, 2003).                 soils helps to prevent nitrite accumulation and
   Wind erodibility index is a numerical value indicating     ammonium-N volatilization.
the susceptibility of soil to wind erosion, or the tons
per acre per year that can be expected to be lost to          Water Features
wind erosion. There is a close correlation between
wind erosion and the texture of the surface layer, the           Table 21 gives estimates of various water features.
size and durability of surface clods, rock fragments,         The estimates are used in land use planning that
organic matter, and a calcareous reaction. Soil               involves engineering considerations.
moisture and frozen soil layers also influence wind              Hydrologic soil groups are based on estimates of
erosion.                                                      runoff potential. Soils are assigned to one of four
                                                              groups according to the rate of water infiltration when
Chemical Properties                                           the soils are not protected by vegetation, are
                                                              thoroughly wet, and receive precipitation from long-
   Table 20 shows estimates of some chemical                  duration storms.
characteristics and features that affect soil behavior.          The four hydrologic soil groups are:
These estimates are given for the layers of each soil in         Group A. Soils having a high infiltration rate (low
the survey area. The estimates are based on field             runoff potential) when thoroughly wet. These consist
observations and on test data for these and similar           mainly of deep, well drained to excessively drained
soils.                                                        sands or gravelly sands. These soils have a high rate
   Depth to the upper and lower boundaries of each            of water transmission.
layer is indicated.                                              Group B. Soils having a moderate infiltration rate
   Soil reaction is a measure of acidity or alkalinity.       when thoroughly wet. These consist chiefly of
The pH of each soil horizon is based on many field            moderately deep or deep, moderately well drained or
tests. For many soils, values have been verified by           well drained soils that have moderately fine texture to
laboratory analyses. Soil reaction is important in            moderately coarse texture. These soils have a
selecting crops and other plants, in evaluating soil          moderate rate of water transmission.
amendments for fertility and stabilization, and in               Group C. Soils having a slow infiltration rate when
determining the risk of corrosion.                            thoroughly wet. These consist chiefly of soils having a
   Organic matter is the plant and animal residue in          layer that impedes the downward movement of water
the soil at various stages of decomposition. In table         or soils of moderately fine texture or fine texture.
20, the estimated content of organic matter is                These soils have a slow rate of water transmission.
expressed as a percentage, by weight, of the soil                Group D. Soils having a very slow infiltration rate
material that is less than 2 millimeters in diameter.         (high runoff potential) when thoroughly wet. These
   The content of organic matter in a soil can be             consist chiefly of clays that have a high shrink-swell
maintained by returning crop residue to the soil.             potential, soils that have a high water table, soils that
Organic matter has a positive effect on available water       have a claypan or clay layer at or near the surface,
142                                                                                                       Soil Survey of




and soils that are shallow over nearly impervious             Frequency is expressed as none, very rare, rare,
material. These soils have a very slow rate of water          occasional, frequent, and very frequent. None means
transmission.                                                 that flooding is not probable; very rare that it is very
    If a soil is assigned to a dual hydrologic group (A/D,    unlikely but possible under extremely unusual weather
B/D, or C/D), the first letter is for drained areas and the   conditions (the chance of flooding is less than 1
second is for undrained areas.                                percent in any year); rare that it is unlikely but possible
    The months in the table indicate the portion of the       under unusual weather conditions (the chance of
year in which the feature is most likely to be a              flooding is 1 to 5 percent in any year); occasional that
concern.                                                      it occurs infrequently under normal weather conditions
    Water table refers to a saturated zone in the soil.       (the chance of flooding is 5 to 50 percent in any year);
Table 21 indicates, by month, depth to the top (upper         frequent that it is likely to occur often under normal
limit ) and base (lower limit ) of the saturated zone in      weather conditions (the chance of flooding is more
most years. Estimates of the upper and lower limits           than 50 percent in any year but is less than 50 percent
are based mainly on observations of the water table at        in all months in any year); and very frequent that it is
selected sites and on evidence of a saturated zone,           likely to occur very often under normal weather
namely grayish colors or mottles (redoximorphic               conditions (the chance of flooding is more than 50
features) in the soil. A saturated zone that lasts for        percent in all months of any year).
less than a month is not considered a water table.                The information is based on evidence in the soil
    Also shown in table 21 is the kind of water table—        profile, namely thin strata of gravel, sand, silt, or clay
that is, apparent or perched. An apparent water table         deposited by floodwater; irregular decrease in organic
is a thick zone of free water in the soil. It is indicated    matter content with increasing depth; and little or no
by the level at which water stands in an uncased              horizon development.
borehole after adequate time is allowed for adjustment            Also considered are local information about the
in the surrounding soil. A perched water table is water       extent and levels of flooding and the relation of each
standing above an unsaturated zone. In places an              soil on the landscape to historic floods. Information on
upper, or perched, water table is separated from a            the extent of flooding based on soil data is less
lower one by a dry zone.                                      specific than that provided by detailed engineering
    Ponding is standing water in a closed depression.         surveys that delineate flood-prone areas at specific
Unless a drainage system is installed, the water is           flood frequency levels.
removed only by percolation, transpiration, or
evaporation. Table 21 indicates surface water depth           Soil Features
and the duration and frequency of ponding. Duration is
expressed as very brief if less than 2 days, brief if 2 to       Table 22 gives estimates of various soil features.
7 days, long if 7 to 30 days, and very long if more than      The estimates are used in land use planning that
30 days. Frequency is expressed as none, rare,                involves engineering considerations.
occasional, and frequent. None means that ponding is             A restrictive layer is a nearly continuous layer that
not probable; rare that it is unlikely but possible under     has one or more physical, chemical, or thermal
unusual weather conditions (the chance of ponding is          properties that significantly impede the movement of
nearly 0 percent to 5 percent in any year); occasional        water and air through the soil or that restrict roots or
that it occurs, on the average, once or less in 2 years       otherwise provide an unfavorable root environment.
(the chance of ponding is 5 to 50 percent in any year);       Examples are bedrock, cemented layers, dense
and frequent that it occurs, on the average, more than        layers, and frozen layers. Depth to top is the vertical
once in 2 years (the chance of ponding is more than           distance from the soil surface to the upper boundary of
50 percent in any year).                                      the restrictive layer.
    Flooding is the temporary inundation of an area              Potential for frost action is the likelihood of upward
caused by overflowing streams, by runoff from                 or lateral expansion of the soil caused by the formation
adjacent slopes, or by tides. Water standing for short        of segregated ice lenses (frost heave) and the
periods after rainfall or snowmelt is not considered          subsequent collapse of the soil and loss of strength on
flooding, and water standing in swamps and marshes            thawing. Frost action occurs when moisture moves
is considered ponding rather than flooding.                   into the freezing zone of the soil. Temperature, texture,
    Duration and frequency are estimated. Duration is         density, permeability, content of organic matter, and
expressed as extremely brief if 0.1 hour to 4 hours,          depth to the water table are the most important factors
very brief if 4 hours to 2 days, brief if 2 to 7 days, long   considered in evaluating the potential for frost action. It
if 7 to 30 days, and very long if more than 30 days.          is assumed that the soil is not insulated by vegetation
Rock Island County, Illinois                                                                                        143




or snow and is not artificially drained. Silty and highly    needed if the combination of factors results in a severe
structured, clayey soils that have a high water table in     hazard of corrosion. The steel or concrete in
winter are the most susceptible to frost action. Well        installations that intersect soil boundaries or soil layers
drained, very gravelly, or very sandy soils are the least    is more susceptible to corrosion than the steel or
susceptible. Frost heave and low soil strength during        concrete in installations that are entirely within one
thawing cause damage to pavements and other rigid            kind of soil or within one soil layer.
structures.                                                     For uncoated steel, the risk of corrosion, expressed
   Risk of corrosion pertains to potential soil-induced      as low, moderate, or high, is based on soil drainage
electrochemical or chemical action that corrodes or          class, total acidity, electrical resistivity near field
weakens uncoated steel or concrete. The rate of              capacity, and electrical conductivity of the saturation
corrosion of uncoated steel is related to such factors       extract.
as soil moisture, particle-size distribution, acidity, and      For concrete, the risk of corrosion also is expressed
electrical conductivity of the soil. The rate of corrosion   as low, moderate, or high. It is based on soil texture,
of concrete is based mainly on the sulfate and sodium        acidity, and amount of sulfates in the saturation
content, texture, moisture content, and acidity of the       extract.
soil. Special site examination and design may be
                                                                                                  145




References
    American Association of State Highway and Transportation Officials (AASHTO). 2000.
    Standard specifications for transportation materials and methods of sampling and
    testing. 20th edition, 2 volumes.

    American Society for Testing and Materials (ASTM). 2001. Standard classification of
    soils for engineering purposes. ASTM Standard D 2487–00.

    Acker, L.L. 1977. Soil survey of Rock Island County, Illinois.

    Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of wetlands
    and deep-water habitats of the United States. U.S. Fish and Wildlife Service FWS/OBS–
    79/31.

    Federal Register. July 13, 1994. Changes in hydric soils of the United States.

    Federal Register. February 24, 1995. Hydric soils of the United States.

    Fehrenbacher, J.B., R.A. Pope, I.J. Jansen, J.D. Alexander, and B.W. Ray. 1978. Soil
    productivity in Illinois. University of Illinois, College of Agriculture, Cooperative
    Extension Service Circular 1156.

    Hurt, G.W., P.M. Whited, and R.F. Pringle, editors. Version 4.0, 1998. Field indicators of
    hydric soils in the United States.

    Illinois Agricultural Statistics Service. 2001. Illinois agricultural statistics annual
    summary.

    Jenny, Hans. 1941. Factors of soil formation.

    Leighton, M.M., and J.A. Brophy. 1961. Illinoian glaciation in Illinois. Journal of Geology
    69: 1–31.

    National Research Council. 1995. Wetlands: Characteristics and boundaries.

    Soil Survey Division Staff. 1993. Soil survey manual. Soil Conservation Service. U.S.
    Department of Agriculture Handbook 18.

    Soil Survey Staff. 1998. Keys to soil taxonomy. 8th edition. U.S. Department of
    Agriculture, Natural Resources Conservation Service.

    Soil Survey Staff. 1999. Soil taxonomy: A basic system of soil classification for making
    and interpreting soil surveys. 2nd edition. Natural Resources Conservation Service.
    U.S. Department of Agriculture Handbook 436.
146




      Tiner, R.W., Jr. 1985. Wetlands of Delaware. U.S. Fish and Wildlife Service and
      Delaware Department of Natural Resources and Environmental Control, Wetlands
      Section.

      United States Army Corps of Engineers, Environmental Laboratory. 1987. Corps of
      Engineers wetlands delineation manual. Waterways Experiment Station Technical
      Report Y–87–1.

      United States Department of Agriculture. 1961. Land capability classification. Soil
      Conservation Service. U.S. Department of Agriculture Handbook 210.

      United States Department of Agriculture. 1981. Land resource regions and major land
      resource areas of the United States. Soil Conservation Service. U.S. Department of
      Agriculture Handbook 296. Map revised 2004.

      United States Department of Agriculture. 2003. National soil survey handbook, title
      430–VI. [Online] Available: http://soils.usda.gov/technical/handbook/.

      United States Department of Commerce, Bureau of the Census. 2002. 2000 census of
      population and housing.

      University of Illinois Agricultural Experiment Station. 1971. Loess soils of northwest
      Illinois. Bulletin 739.

      Willman, H.B., and J.C. Frye. 1970. Pleistocene stratigraphy of Illinois. Illinois Geological
      Survey Bulletin 94.
                                                                                                                                            147




Glossary
Aeration, soil. The exchange of air in soil with air from                                  convex shoulder above and a concave footslope
    the atmosphere. The air in a well aerated soil is                                      below.
    similar to that in the atmosphere; the air in a                                     Base saturation. The degree to which material having
    poorly aerated soil is considerably higher in                                          cation-exchange properties is saturated with
    carbon dioxide and lower in oxygen.                                                    exchangeable bases (sum of Ca, Mg, Na, and K),
Aggregate, soil. Many fine particles held in a single                                      expressed as a percentage of the total cation-
    mass or cluster. Natural soil aggregates, such as                                      exchange capacity.
    granules, blocks, or prisms, are called peds. Clods                                 Beach deposits. Material, such as sand and gravel,
    are aggregates produced by tillage or logging.                                         that is generally laid down parallel to an active or
Alluvium. Material, such as sand, silt, or clay,                                           relict shoreline of a postglacial or glacial lake.
    deposited on land by streams.                                                       Beach ridge. A low, essentially continuous mound of
Alpha,alpha-dipyridyl. A dye that when dissolved in                                        beach or beach-and-dune material accumulated
    1N ammonium acetate is used to detect the                                              by the action of waves and currents on the
    presence of reduced iron (Fe II) in the soil. A                                        backshore of a beach, beyond the present limit of
    positive reaction indicates a type of redoximorphic                                    storm waves or the reach of ordinary tides. The
    feature.                                                                               ridges are roughly parallel to the shoreline and
Animal unit month (AUM). The amount of forage                                              represent successive positions of an advancing
    required by one mature cow of approximately                                            shoreline.
    1,000 pounds weight, with or without a calf, for 1                                  Bedding planes. Fine strata, less than 5 millimeters
    month.                                                                                 thick, in unconsolidated alluvial, eolian, lacustrine,
Aquic conditions. Current soil wetness characterized                                       or marine sediment.
    by saturation, reduction, and redoximorphic                                         Bedrock. The solid rock that underlies the soil and
    features.                                                                              other unconsolidated material or that is exposed at
Argillic horizon. A subsoil horizon characterized by                                       the surface.
    an accumulation of illuvial clay.                                                   Bedrock-controlled topography. A landscape where
Aspect. The direction in which a slope faces.                                              the configuration and relief of the landforms are
Available water capacity (available moisture                                               determined or strongly influenced by the
    capacity). The capacity of soils to hold water                                         underlying bedrock.
    available for use by most plants. It is commonly                                    Bench terrace. A raised, level or nearly level strip of
    defined as the difference between the amount of                                        earth constructed on or nearly on a contour,
    soil water at field moisture capacity and the                                          supported by a barrier of rocks or similar material,
    amount at wilting point. It is commonly expressed                                      and designed to make the soil suitable for tillage
    as inches of water per inch of soil. The capacity, in                                  and to prevent accelerated erosion.
    inches, in a 60-inch profile or to a limiting layer is                              Bisequum. Two sequences of soil horizons, each of
    expressed as:                                                                          which consists of an illuvial horizon and the
       Very low ............................................................ 0 to 3        overlying eluvial horizons.
       Low ................................................................... 3 to 6   Boulders. Rock fragments larger than 2 feet (60
       Moderate .......................................................... 6 to 9          centimeters) in diameter.
       High ................................................................ 9 to 12    Calcareous soil. A soil containing enough calcium
       Very high .............................................. more than 12               carbonate (commonly combined with magnesium
                                                                                           carbonate) to effervesce visibly when treated with
Backslope. The position that forms the steepest and                                        cold, dilute hydrochloric acid.
   generally linear, middle portion of a hillslope. In                                  Capillary water. Water held as a film around soil
   profile, backslopes are commonly bounded by a                                           particles and in tiny spaces between particles.
148                                                                                                   Soil Survey of




    Surface tension is the adhesive force that holds           The pattern and proportion of the soils or
    capillary water in the soil.                               miscellaneous areas are somewhat similar in all
Catena. A sequence, or “chain,” of soils on a                  areas.
    landscape that formed in similar kinds of parent        Concretions. Cemented bodies with crude internal
    material but have different characteristics as a           symmetry organized around a point, a line, or a
    result of differences in relief and drainage.              plane. They typically take the form of concentric
Cation. An ion carrying a positive charge of electricity.      layers visible to the naked eye. Calcium carbonate,
    The common soil cations are calcium, potassium,            iron oxide, and manganese oxide are common
    magnesium, sodium, and hydrogen.                           compounds making up concretions. If formed in
Cation-exchange capacity. The total amount of                  place, concretions of iron oxide or manganese
    exchangeable cations that can be held by the soil,         oxide are generally considered a type of
    expressed in terms of milliequivalents per 100             redoximorphic concentration.
    grams of soil at neutrality (pH 7.0) or at some         Conservation cropping system. Growing crops in
    other stated pH value. The term, as applied to             combination with needed cultural and
    soils, is synonymous with base-exchange capacity           management practices. In a good conservation
    but is more precise in meaning.                            cropping system, the soil-improving crops and
Chiseling. Tillage with an implement having one or             practices more than offset the effects of the soil-
    more soil-penetrating points that shatter or loosen        depleting crops and practices. Cropping systems
    hard, compacted layers to a depth below normal             are needed on all tilled soils. Soil-improving
    plow depth.                                                practices in a conservation cropping system
Clay. As a soil separate, the mineral soil particles less      include the use of rotations that contain grasses
    than 0.002 millimeter in diameter. As a soil textural      and legumes and the return of crop residue to the
    class, soil material that is 40 percent or more clay,      soil. Other practices include the use of green
    less than 45 percent sand, and less than 40                manure crops of grasses and legumes, proper
    percent silt.                                              tillage, adequate fertilization, and weed and pest
Clay depletions. Low-chroma zones having a low                 control.
    content of iron, manganese, and clay because of         Conservation tillage. A tillage system that does not
    the chemical reduction of iron and manganese               invert the soil and that leaves a protective amount
    and the removal of iron, manganese, and clay. A            of crop residue on the surface throughout the year.
    type of redoximorphic depletion.                        Consistence, soil. Refers to the degree of cohesion
Clay film. A thin coating of oriented clay on the              and adhesion of soil material and its resistance to
    surface of a soil aggregate or lining pores or root        deformation when ruptured. Consistence includes
    channels. Synonyms: clay coating, clay skin.               resistance of soil material to rupture and to
Clayey soil. Silty clay, sandy clay, or clay.                  penetration; plasticity, toughness, and stickiness of
Closed depression. A low area completely                       puddled soil material; and the manner in which the
    surrounded by higher ground and having no                  soil material behaves when subject to
    natural outlet.                                            compression. Terms describing consistence are
Coarse textured soil. Sand or loamy sand.                      defined in the “Soil Survey Manual.”
Cobble (or cobblestone). A rounded or partly                Contour stripcropping. Growing crops in strips that
    rounded fragment of rock 3 to 10 inches (7.6 to 25         follow the contour. Strips of grass or close-growing
    centimeters) in diameter.                                  crops are alternated with strips of clean-tilled
COLE (coefficient of linear extensibility). See                crops or summer fallow.
    Linear extensibility.                                   Control section. The part of the soil on which
Colluvium. Soil material or rock fragments, or both,           classification is based. The thickness varies
    moved by creep, slide, or local wash and                   among different kinds of soil, but for many it is that
    deposited at the base of steep slopes.                     part of the soil profile between depths of 10 inches
Complex slope. Irregular or variable slope. Planning           and 40 or 80 inches.
    or establishing terraces, diversions, and other         Corrosion. Soil-induced electrochemical or chemical
    water-control structures on a complex slope is             action that dissolves or weakens concrete or
    difficult.                                                 uncoated steel.
Complex, soil. A map unit of two or more kinds of soil      Cover crop. A close-growing crop grown primarily to
    or miscellaneous areas in such an intricate pattern        improve and protect the soil between periods of
    or so small in area that it is not practical to map        regular crop production, or a crop grown between
    them separately at the selected scale of mapping.          trees and vines in orchards and vineyards.
Rock Island County, Illinois                                                                                     149




Crop residue management. Returning crop residue               within the soil. Soil horizons that have lost material
   to the soil, which helps to maintain soil structure,       through eluviation are eluvial; those that have
   organic matter content, and fertility and helps to         received material are illuvial.
   control erosion.                                       Endosaturation. A type of saturation of the soil in
Cropping system. Growing crops according to a                 which all horizons between the upper boundary of
   planned system of rotation and management                  saturation and a depth of 2 meters are saturated.
   practices.                                             Eolian soil material. Earthy parent material
Culmination of the mean annual increment (CMAI).              accumulated through wind action; commonly
   The average annual increase per acre in the                refers to sandy material in dunes or to loess in
   volume of a stand. Computed by dividing the total          blankets on the surface.
   volume of the stand by its age. As the stand           Episaturation. A type of saturation indicating a
   increases in age, the mean annual increment                perched water table in a soil in which saturated
   continues to increase until mortality begins to            layers are underlain by one or more unsaturated
   reduce the rate of increase. The point where the           layers within 2 meters of the surface.
   stand reaches its maximum annual rate of growth        Erosion. The wearing away of the land surface by
   is called the culmination of the mean annual               water, wind, ice, or other geologic agents and by
   increment.                                                 such processes as gravitational creep.
Cutbanks cave (in tables). The walls of excavations           Erosion (geologic). Erosion caused by geologic
   tend to cave in or slough.                                 processes acting over long geologic periods and
Deferred grazing. Postponing grazing or resting               resulting in the wearing away of mountains and
   grazing land for a prescribed period.                      the building up of such landscape features as
Depth, soil. Generally, the thickness of the soil over        flood plains and coastal plains. Synonym: natural
   bedrock. Very deep soils are more than 60 inches           erosion.
   deep over bedrock; deep soils, 40 to 60 inches;            Erosion (accelerated). Erosion much more rapid
   moderately deep, 20 to 40 inches; shallow, 10 to           than geologic erosion, mainly as a result of human
   20 inches; and very shallow, less than 10 inches.          or animal activities or of a catastrophe in nature,
Diversion (or diversion terrace). A ridge of earth,           such as a fire, that exposes the surface.
   generally a terrace, built to protect downslope        Escarpment. A relatively continuous and steep slope
   areas by diverting runoff from its natural course.         or cliff breaking the general continuity of more
Drainage class (natural). Refers to the frequency and         gently sloping land surfaces and resulting from
   duration of wet periods under conditions similar to        erosion or faulting. Synonym: scarp.
   those under which the soil formed. Alterations of      Fertility, soil. The quality that enables a soil to provide
   the water regime by human activities, either               plant nutrients, in adequate amounts and in proper
   through drainage or irrigation, are not a                  balance, for the growth of specified plants when
   consideration unless they have significantly               light, moisture, temperature, tilth, and other growth
   changed the morphology of the soil. Seven                  factors are favorable.
   classes of natural soil drainage are recognized—       Fibric soil material (peat). The least decomposed of
   excessively drained, somewhat excessively                  all organic soil material. Peat contains a large
   drained, well drained, moderately well drained,            amount of well preserved fiber that is readily
   somewhat poorly drained, poorly drained, and               identifiable according to botanical origin. Peat has
   very poorly drained. These classes are defined in          the lowest bulk density and the highest water
   the “Soil Survey Manual.”                                  content at saturation of all organic soil material.
Drainage, surface. Runoff, or surface flow of water,      Field moisture capacity. The moisture content of a
   from an area.                                              soil, expressed as a percentage of the ovendry
Drainageway. An area of ground at a lower elevation           weight, after the gravitational, or free, water has
   than the surrounding ground and in which water             drained away; the field moisture content 2 or 3
   collects and is drained to a closed depression or          days after a soaking rain; also called normal field
   lake or to a drainageway at a lower elevation. A           capacity, normal moisture capacity, or capillary
   drainageway may or may not have distinctly                 capacity.
   incised channels at its upper reaches or               Fine textured soil. Sandy clay, silty clay, or clay.
   throughout its course.                                 Flood plain. A nearly level alluvial plain that borders a
Eluviation. The movement of material in true solution         stream and is subject to flooding unless protected
   or colloidal suspension from one place to another          artificially.
150                                                                                                    Soil Survey of




Flood-plain splay. A fan-shaped deposit or other           Gravelly soil material. Material that has 15 to 35
   outspread deposit formed where an overloaded                percent, by volume, rounded or angular rock
   stream breaks through a levee (natural or artificial)       fragments, not prominently flattened, as much as
   and deposits its material (commonly coarse                  3 inches (7.6 centimeters) in diameter.
   grained) on the flood plain.                            Green manure crop (agronomy). A soil-improving
Footslope. The position that forms the inner, gently           crop grown to be plowed under in an early stage
   inclined surface at the base of a hillslope. In             of maturity or soon after maturity.
   profile, footslopes are commonly concave. A             Ground water (geology). Water filling all the unblocked
   footslope is a transition zone between upslope              pores of the material below the water table.
   sites of erosion and transport (shoulders and           Gully. A miniature valley with steep sides cut by
   backslopes) and downslope sites of deposition               running water and through which water ordinarily
   (toeslopes).                                                runs only after rainfall. The distinction between a
Forb. Any herbaceous plant not a grass or a sedge.             gully and a rill is one of depth. A gully generally is
Frost action (in tables). Freezing and thawing of soil         an obstacle to farm machinery and is too deep to
   moisture. Frost action can damage roads,                    be obliterated by ordinary tillage; a rill is of lesser
   buildings and other structures, and plant roots.            depth and can be smoothed over by ordinary
Genesis, soil. The mode of origin of the soil. Refers          tillage.
   especially to the processes or soil-forming factors     Hard bedrock. Bedrock that cannot be excavated
   responsible for the formation of the solum, or true         except by blasting or by the use of special
   soil, from the unconsolidated parent material.              equipment that is not commonly used in
Glacial drift (geology). Pulverized and other rock             construction.
   material transported by glacial ice and then            Hard to reclaim (in tables). Reclamation is difficult
   deposited. Also, the sorted and unsorted material           after the removal of soil for construction and other
   deposited by streams flowing from glaciers.                 uses. Revegetation and erosion control are
Glacial outwash (geology). Gravel, sand, and silt,             extremely difficult.
   commonly stratified, deposited by glacial               Head slope. A geomorphic component of hills
   meltwater.                                                  consisting of a laterally concave area of a hillside,
Glacial till (geology). Unsorted, nonstratified glacial        especially at the head of a drainageway. The
   drift consisting of clay, silt, sand, and boulders          overland waterflow is converging.
   transported and deposited by glacial ice.               Hemic soil material (mucky peat). Organic soil
Glaciated uplands. Land areas that were previously             material intermediate in degree of decomposition
   covered by continental or alpine glaciers and that          between the less decomposed fibric material and
   are at a higher elevation than the flood plain.             the more decomposed sapric material.
Glaciofluvial deposits (geology). Material moved by        Horizon, soil. A layer of soil, approximately parallel to
   glaciers and subsequently sorted and deposited              the surface, having distinct characteristics
   by streams flowing from the melting ice. The                produced by soil-forming processes. In the
   deposits are stratified and occur as kames,                 identification of soil horizons, an uppercase letter
   eskers, deltas, and outwash plains.                         represents the major horizons. Numbers or
Glaciolacustrine deposits (geology). Material                  lowercase letters that follow represent
   ranging from fine clay to sand derived from                 subdivisions of the major horizons. An explanation
   glaciers and deposited in glacial lakes mainly by           of the subdivisions is given in the “Soil Survey
   glacial meltwater. Many deposits are interbedded            Manual.” The major horizons of mineral soil are as
   or laminated.                                               follows:
Gleyed soil. Soil that formed under poor drainage,             O horizon.—An organic layer of fresh and
   resulting in the reduction of iron and other                decaying plant residue.
   elements in the profile and in gray colors.                 A horizon.—The mineral horizon at or near the
Grassed waterway. A natural or constructed                     surface in which an accumulation of humified
   waterway, typically broad and shallow, seeded to            organic matter is mixed with the mineral material.
   grass as protection against erosion. Conducts               Also, a plowed surface horizon, most of which was
   surface water away from cropland.                           originally part of a B horizon.
Gravel. Rounded or angular fragments of rock as                E horizon.—The mineral horizon in which the main
   much as 3 inches (2 millimeters to 7.6                      feature is loss of silicate clay, iron, aluminum, or
   centimeters) in diameter. An individual piece is a          some combination of these.
   pebble.                                                     B horizon.—The mineral horizon below an A
Rock Island County, Illinois                                                                                                                          151




     horizon. The B horizon is in part a layer of                  rate; the rate decreases with application time.
     transition from the overlying A to the underlying C           Therefore, intake rate for design purposes is not a
     horizon. The B horizon also has distinctive                   constant but is a variable depending on the net
     characteristics, such as (1) accumulation of clay,            irrigation application. The rate of water intake, in
     sesquioxides, humus, or a combination of these;               inches per hour, is expressed as follows:
     (2) prismatic or blocky structure; (3) redder or                 Less than 0.2 ............................................... very low
     browner colors than those in the A horizon; or (4)               0.2 to 0.4 .............................................................. low
     a combination of these.                                          0.4 to 0.75 ......................................... moderately low
     C horizon.—The mineral horizon or layer,                         0.75 to 1.25 ................................................ moderate
     excluding indurated bedrock, that is little affected             1.25 to 1.75 ..................................... moderately high
     by soil-forming processes and does not have the                  1.75 to 2.5 .......................................................... high
     properties typical of the overlying soil material.               More than 2.5 ............................................. very high
     The material of a C horizon may be either like or
     unlike that in which the solum formed. If the             Interfluve. An elevated area between two
     material is known to differ from that in the solum,            drainageways that sheds water to those
     an Arabic numeral, commonly a 2, precedes the                  drainageways.
     letter C.                                                 Intermittent stream. A stream, or reach of a stream,
     Cr horizon.—Soft, consolidated bedrock beneath                 that flows for prolonged periods only when it
     the soil.                                                      receives ground-water discharge or long,
     R layer.—Consolidated bedrock beneath the soil.                continued contributions from melting snow or other
     The bedrock commonly underlies a C horizon, but                surface and shallow subsurface sources.
     it can be directly below an A or a B horizon.             Iron depletions. Low-chroma zones having a low
Humus. The well decomposed, more or less stable                     content of iron and manganese oxide because of
     part of the organic matter in mineral soils.                   chemical reduction and removal, but having a clay
Hydrologic soil groups. Refers to soils grouped                     content similar to that of the adjacent matrix. A
     according to their runoff potential. The soil                  type of redoximorphic depletion.
     properties that influence this potential are those        Irrigation. Application of water to soils to assist in
     that affect the minimum rate of water infiltration on          production of crops. Typical methods of irrigation
     a bare soil during periods after prolonged wetting             used in the survey area are:
     when the soil is not frozen. These properties are              Drip (or trickle).—Water is applied slowly and
     depth to a seasonal high water table, the                      under low pressure to the surface of the soil or
     infiltration rate and permeability after prolonged             into the soil through such applicators as emitters,
     wetting, and depth to a very slowly permeable                  porous tubing, or perforated pipe.
     layer. The slope and the kind of plant cover are not           Sprinkler.—Water is sprayed over the soil surface
     considered but are separate factors in predicting              through pipes or nozzles from a pressure system.
     runoff.                                                   Karst (topography). The relief of an area underlain by
Illuviation. The movement of soil material from one                 limestone that dissolves in differing degrees, thus
     horizon to another in the soil profile. Generally,             forming numerous depressions or small basins.
     material is removed from an upper horizon and             Ksat. Saturated hydraulic conductivity. (See
     deposited in a lower horizon.                                  Permeability.)
Infiltration. The downward entry of water into the             Lacustrine deposit (geology). Material deposited in
     immediate surface of soil or other material, as                lake water and exposed when the water level is
     contrasted with percolation, which is movement of              lowered or the elevation of the land is raised.
     water through soil layers or material.                    Lake plain. A nearly level surface marking the floor of
Infiltration capacity. The maximum rate at which                    an extinct lake filled by well sorted, generally fine
     water can infiltrate into a soil under a given set of          textured, stratified deposits, commonly containing
     conditions.                                                    varves.
Infiltration rate. The rate at which water penetrates          Leaching. The removal of soluble material from soil or
     the surface of the soil at any given instant, usually          other material by percolating water.
     expressed in inches per hour. The rate can be             Linear extensibility. Refers to the change in length of
     limited by the infiltration capacity of the soil or the        an unconfined clod as moisture content is
     rate at which water is applied at the surface.                 decreased from a moist to a dry state. Linear
Intake rate. The average rate of water entering the                 extensibility is used to determine the shrink-swell
     soil under irrigation. Most soils have a fast initial          potential of soils. It is an expression of the volume
152                                                                                                                       Soil Survey of




   change between the water content of the clod at         Morphology, soil. The physical makeup of the soil,
      1
    /3- or 1/10-bar tension (33kPa or 10kPa tension)          including the texture, structure, porosity,
   and oven dryness. Volume change is influenced by           consistence, color, and other physical, mineral,
   the amount and type of clay minerals in the soil.          and biological properties of the various horizons,
   The volume change is the percent change for the            and the thickness and arrangement of those
   whole soil. If it is expressed as a fraction, the          horizons in the soil profile.
   resulting value is COLE, coefficient of linear          Mottling, soil. Irregular spots of different colors that
   extensibility.                                             vary in number and size. Descriptive terms are as
Liquid limit. The moisture content at which the soil          follows: abundance—few, common, and many;
   passes from a plastic to a liquid state.                   size—fine, medium, and coarse; and contrast—
Loam. Soil material that is 7 to 27 percent clay              faint, distinct, and prominent. The size
   particles, 28 to 50 percent silt particles, and less       measurements are of the diameter along the
   than 52 percent sand particles.                            greatest dimension. Fine indicates less than 5
Loamy soil. Coarse sandy loam, sandy loam, fine               millimeters (about 0.2 inch); medium, from 5 to 15
   sandy loam, very fine sandy loam, loam, silt loam,         millimeters (about 0.2 to 0.6 inch); and coarse,
   silt, clay loam, sandy clay loam, or silty clay loam.      more than 15 millimeters (about 0.6 inch).
Loess. Fine grained material, dominantly of silt-sized     Muck. Dark, finely divided, well decomposed organic
   particles, deposited by wind.                              soil material. (See Sapric soil material.)
Low strength. The soil is not strong enough to             Munsell notation. A designation of color by degrees
   support loads.                                             of three simple variables—hue, value, and
Masses. Concentrations of substances in the soil              chroma. For example, a notation of 10YR 6/4 is
   matrix that do not have a clearly defined boundary         a color with hue of 10YR, value of 6, and chroma
   with the surrounding soil material and cannot be           of 4.
   removed as a discrete unit. Common compounds            Neutral soil. A soil having a pH value of 6.6 to 7.3.
   making up masses are calcium carbonate,                    (See Reaction, soil.)
   gypsum or other soluble salts, iron oxide, and          Nodules. Cemented bodies lacking visible internal
   manganese oxide. Masses consisting of iron oxide           structure. Calcium carbonate, iron oxide, and
   or manganese oxide generally are considered a              manganese oxide are common compounds
   type of redoximorphic concentration.                       making up nodules. If formed in place, nodules of
Medium textured soil. Very fine sandy loam, loam,             iron oxide or manganese oxide are considered
   silt loam, or silt.                                        types of redoximorphic concentrations.
Mineral soil. Soil that is mainly mineral material and     Nose slope. A geomorphic component of hills
   low in organic material. Its bulk density is more          consisting of the projecting end (laterally convex
   than that of organic soil.                                 area) of a hillside. The overland waterflow is
Minimum tillage. Only the tillage essential to crop           predominantly divergent.
   production and prevention of soil damage.               Nutrient, plant. Any element taken in by a plant
Miscellaneous area. An area that has little or no             essential to its growth. Plant nutrients are mainly
   natural soil and supports little or no vegetation.         nitrogen, phosphorus, potassium, calcium,
MLRA (Major Land Resource Area). A geographic                 magnesium, sulfur, iron, manganese, copper,
   area characterized by a particular pattern of              boron, and zinc obtained from the soil and carbon,
   land uses, elevation and topography, soils,                hydrogen, and oxygen obtained from the air and
   climate, water resources, and potential natural            water.
   vegetation.                                             Organic matter. Plant and animal residue in the soil in
Moderately coarse textured soil. Coarse sandy                 various stages of decomposition. The content of
   loam, sandy loam, or fine sandy loam.                      organic matter in the surface layer is described as
Moderately fine textured soil. Clay loam, sandy clay          follows:
   loam, or silty clay loam.                                      Very low ................................... less than 0.5 percent
Mollic epipedon. A thick, dark, humus-rich surface                Low ................................................ 0.5 to 1.0 percent
   horizon (or horizons) that has high base saturation            Moderately low .............................. 1.0 to 2.0 percent
   and pedogenic soil structure. It may include the               Moderate ....................................... 2.0 to 4.0 percent
   upper part of the subsoil.                                     High ............................................... 4.0 to 8.0 percent
Moraine. An accumulation of earth, stones, and other              Very high ............................... more than 8.0 percent
   debris deposited by a glacier. Some types are
   terminal, lateral, medial, and ground.                  Outwash plain. A landform of mainly sandy or coarse
Rock Island County, Illinois                                                                                                                                           153




    textured material of glaciofluvial origin. An                                     pipelike cavities by water moving through the
    outwash plain is commonly smooth; where pitted,                                   soil.
    it generally is low in relief.                                                Plastic limit. The moisture content at which a soil
Parent material. The unconsolidated organic and                                       changes from semisolid to plastic.
    mineral material in which soil forms.                                         Plasticity index. The numerical difference between
Particle-size control section. The part of the soil                                   the liquid limit and the plastic limit; the range of
    profile on which calculations of particle-size                                    moisture content within which the soil remains
    classes are based. The thickness can vary                                         plastic.
    depending on specific soil properties, but for many                           Plowpan. A compacted layer formed in the soil
    soils the particle-size control section is from 25 to                             directly below the plowed layer.
    100 centimeters.                                                              Ponding. Standing water on soils in closed
Peat. Unconsolidated material, largely undecomposed                                   depressions. Unless the soils are artificially
    organic matter, that has accumulated under                                        drained, the water can be removed only by
    excess moisture. (See Fibric soil material.)                                      percolation or evapotranspiration.
Ped. An individual natural soil aggregate, such as a                              Poorly graded. Refers to a coarse grained soil or soil
    granule, a prism, or a block.                                                     material consisting mainly of particles of nearly
Pedisediment. A thin layer of alluvial material that                                  the same size. Because there is little difference in
    mantles an erosion surface and has been                                           size of the particles, density can be increased only
    transported to its present position from higher                                   slightly by compaction.
    lying areas of the erosion surface.                                           Potential rooting depth (effective rooting depth).
Pedon. The smallest volume that can be called “a soil.”                               Depth to which roots could penetrate if the content
    A pedon is three dimensional and large enough to                                  of moisture in the soil were adequate. The soil has
    permit study of all horizons. Its area ranges from                                no properties restricting the penetration of roots to
    about 10 to 100 square feet (1 square meter to 10                                 this depth.
    square meters), depending on the variability of the                           Productivity, soil. The capability of a soil for
    soil.                                                                             producing a specified plant or sequence of plants
Percolation. The movement of water through the soil.                                  under specific management.
Permeability. The quality of the soil that enables water                          Profile, soil. A vertical section of the soil extending
    or air to move downward through the profile. The                                  through all its horizons and into the parent
    rate at which a saturated soil transmits water is                                 material.
    accepted as a measure of this quality. In soil                                Reaction, soil. A measure of acidity or alkalinity of a
    physics, the rate is referred to as “saturated                                    soil, expressed in pH values. A soil that tests to pH
    hydraulic conductivity,” which is defined in the “Soil                            7.0 is described as precisely neutral in reaction
    Survey Manual.” In line with conventional usage in                                because it is neither acid nor alkaline. The
    the engineering profession and with traditional                                   degrees of acidity or alkalinity, expressed as pH
    usage in published soil surveys, this rate of flow                                values, are:
    continues to be expressed as “permeability.” Terms                                   Ultra acid .............................................. less than 3.5
    describing permeability, measured in inches per                                      Extremely acid ........................................... 3.5 to 4.4
    hour, are as follows:                                                                Very strongly acid ...................................... 4.5 to 5.0
       Impermeable ........................... less than 0.0015 inch                     Strongly acid .............................................. 5.1 to 5.5
       Very slow .................................... 0.0015 to 0.06 inch                Moderately acid .......................................... 5.6 to 6.0
       Slow .................................................. 0.06 to 0.2 inch          Slightly acid ................................................ 6.1 to 6.5
       Moderately slow ................................. 0.2 to 0.6 inch                 Neutral ........................................................ 6.6 to 7.3
       Moderate ................................ 0.6 inch to 2.0 inches                  Slightly alkaline .......................................... 7.4 to 7.8
       Moderately rapid ............................ 2.0 to 6.0 inches                   Moderately alkaline .................................... 7.9 to 8.4
       Rapid ............................................... 6.0 to 20 inches            Strongly alkaline ........................................ 8.5 to 9.0
       Very rapid ................................. more than 20 inches                  Very strongly alkaline ......................... 9.1 and higher

pH value. A numerical designation of acidity and                                  Redoximorphic concentrations. Nodules,
    alkalinity in soil. (See Reaction, soil.)                                        concretions, soft masses, pore linings, and other
Phase, soil. A subdivision of a soil series based on                                 features resulting from the accumulation of iron or
    features that affect its use and management, such                                manganese oxide. An indication of chemical
    as slope, stoniness, and flooding.                                               reduction and oxidation resulting from saturation.
Piping (in tables). Formation of subsurface tunnels or                            Redoximorphic depletions. Low-chroma zones from
154                                                                                                       Soil Survey of




     which iron and manganese oxide or a combination               density, and the lowest water content at saturation
     of iron and manganese oxide and clay has been                 of all organic soil material.
     removed. These zones are indications of the              Saturated hydraulic conductivity (Ksat). See
     chemical reduction of iron resulting from                     Permeability.
     saturation.                                              Saturation. Wetness characterized by zero or positive
Redoximorphic features. Redoximorphic                              pressure of the soil water. Under conditions of
     concentrations, redoximorphic depletions, reduced             saturation, the water will flow from the soil matrix
     matrices, a positive reaction to alpha,alpha-                 into an unlined auger hole.
     dipyridyl, and other features indicating the             Sedimentary rock. Rock made up of particles
     chemical reduction and oxidation of iron and                  deposited from suspension in water. The chief
     manganese compounds resulting from saturation.                kinds of sedimentary rock are conglomerate,
Reduced matrix. A soil matrix that has low chroma in               formed from gravel; sandstone, formed from sand;
     situ because of chemically reduced iron (Fe II).              shale, formed from clay; and limestone, formed
     The chemical reduction results from nearly                    from soft masses of calcium carbonate. There are
     continuous wetness. The matrix undergoes a                    many intermediate types. Some wind-deposited
     change in hue or chroma within 30 minutes after               sand is consolidated into sandstone.
     exposure to air as the iron is oxidized (Fe III). A      Seepage (in tables). The movement of water through
     type of redoximorphic feature.                                the soil. Seepage adversely affects the specified
Regolith. The unconsolidated mantle of weathered                   use.
     rock and soil material on the earth’s surface; the       Sequum. A sequence consisting of an illuvial horizon
     loose earth material above the solid rock.                    and the overlying eluvial horizon. (See Eluviation.)
Relief. The elevations or inequalities of a land surface,     Series, soil. A group of soils that have profiles that are
     considered collectively.                                      almost alike, except for differences in texture of
Residuum (residual soil material). Unconsolidated,                 the surface layer. All the soils of a series have
     weathered or partly weathered mineral material                horizons that are similar in composition, thickness,
     that accumulated as consolidated rock                         and arrangement.
     disintegrated in place.                                  Shale. Sedimentary rock formed by the hardening of a
Rill. A steep-sided channel resulting from accelerated             clay deposit.
     erosion. A rill generally is a few inches deep and       Sheet erosion. The removal of a fairly uniform layer of
     not wide enough to be an obstacle to farm                     soil material from the land surface by the action of
     machinery.                                                    rainfall and surface runoff.
Rock fragments. Rock or mineral fragments having a            Shoulder. The position that forms the uppermost
     diameter of 2 millimeters or more; for example,               inclined surface near the top of a hillslope. It is a
     pebbles, cobbles, stones, and boulders.                       transition from backslope to summit. The surface
Rock outcrop. Exposures of bare bedrock other than                 is dominantly convex in profile and erosional in
     lava flows and rocklined pits.                                origin.
Root zone. The part of the soil that can be penetrated        Shrink-swell (in tables). The shrinking of soil when
     by plant roots.                                               dry and the swelling when wet. Shrinking and
Runoff. The precipitation discharged into stream                   swelling can damage roads, dams, building
     channels from an area. The water that flows off the           foundations, and other structures. It can also
     surface of the land without sinking into the soil is          damage plant roots.
     called surface runoff. Water that enters the soil        Side slope. A geomorphic component of hills
     before reaching surface streams is called ground-             consisting of a laterally planar area of a hillside.
     water runoff or seepage flow from ground water.               The overland waterflow is predominantly parallel.
Sand. As a soil separate, individual rock or mineral          Silt. As a soil separate, individual mineral particles
     fragments from 0.05 millimeter to 2.0 millimeters in          that range in diameter from the upper limit of clay
     diameter. Most sand grains consist of quartz. As a            (0.002 millimeter) to the lower limit of very fine
     soil textural class, a soil that is 85 percent or more        sand (0.05 millimeter). As a soil textural class, soil
     sand and not more than 10 percent clay.                       that is 80 percent or more silt and less than 12
Sandy soil. Sand or loamy sand.                                    percent clay.
Sapric soil material (muck). The most highly                  Similar soils. Soils that share limits of diagnostic
     decomposed of all organic soil material. Muck has             criteria, behave and perform in a similar manner,
     the least amount of plant fiber, the highest bulk             and have similar conservation needs or
Rock Island County, Illinois                                                                                                              155




    management requirements for the major land uses                                      the material in these horizons are unlike those of
    in the survey area.                                                                  the material below the solum. The living roots and
Sinkhole. A depression in the landscape where                                            plant and animal activities are largely confined to
    limestone has been dissolved.                                                        the solum.
Site index. A designation of the quality of a forest site                            Stones. Rock fragments 10 to 24 inches (25 to 60
    based on the height of the dominant stand at an                                      centimeters) in diameter if rounded or 15 to 24
    arbitrarily chosen age. For example, if the average                                  inches (38 to 60 centimeters) in length if flat.
    height attained by dominant and codominant trees                                 Stony. Refers to a soil containing stones in numbers
    in a fully stocked stand at the age of 50 years is                                   that interfere with or prevent tillage.
    75 feet, the site index is 75.                                                   Stream channel. The hollow bed where a natural
Slackwater. A still body of water in a stream.                                           stream of surface water flows or may flow; the
Slickensides. Polished and grooved surfaces                                              deepest or central part of the bed, formed by the
    produced by one mass sliding past another. In                                        main current and covered more or less
    soils, slickensides may occur at the bases of slip                                   continuously by water.
    surfaces on the steeper slopes; on faces of blocks,                              Stream terrace. One of a series of platforms in a
    prisms, and columns; and in swelling clayey soils,                                   stream valley, flanking and more or less parallel to
    where there is marked change in moisture                                             the stream channel. It originally formed near the
    content.                                                                             level of the stream and is the dissected remnants
Slope. The inclination of the land surface from the                                      of an abandoned flood plain, streambed, or valley
    horizontal. Percentage of slope is the vertical                                      floor that were produced during a former stage of
    distance divided by horizontal distance, then                                        erosion or deposition.
    multiplied by 100. Thus, a slope of 20 percent is a                              Stripcropping. Growing crops in a systematic
    drop of 20 feet in 100 feet of horizontal distance.                                  arrangement of strips or bands that provide
Slope (in tables). Slope is great enough that special                                    vegetative barriers to wind erosion and water
    practices are required to ensure satisfactory                                        erosion.
    performance of the soil for a specific use.                                      Structure, soil. The arrangement of primary soil
Slow refill (in tables). The slow filling of ponds,                                      particles into compound particles or aggregates.
    resulting from restricted permeability in the soil.                                  The principal forms of soil structure are—platy
Soft bedrock. Bedrock that can be excavated with                                         (laminated), prismatic (vertical axis of aggregates
    trenching machines, backhoes, small rippers, and                                     longer than horizontal), columnar (prisms with
    other equipment commonly used in construction.                                       rounded tops), blocky (angular or subangular),
Soil. A natural, three-dimensional body at the earth’s                                   and granular. Structureless soils are either single
    surface. It is capable of supporting plants and has                                  grain (each grain by itself, as in dune sand) or
    properties resulting from the integrated effect of                                   massive (the particles adhering without any
    climate and living matter acting on earthy parent                                    regular cleavage, as in many hardpans).
    material, as conditioned by relief and by the                                    Stubble mulch. Stubble or other crop residue left on
    passage of time.                                                                     the soil or partly worked into the soil. It protects
Soil separates. Mineral particles less than 2                                            the soil from wind erosion and water erosion after
    millimeters in equivalent diameter and ranging                                       harvest, during preparation of a seedbed for the
    between specified size limits. The names and                                         next crop, and during the early growing period of
    sizes, in millimeters, of separates recognized in                                    the new crop.
    the United States are as follows:                                                Subsoil. Technically, the B horizon; roughly, the part of
       Very coarse sand ....................................... 2.0 to 1.0               the solum below plow depth.
       Coarse sand ............................................... 1.0 to 0.5        Subsoiling. Tilling a soil below normal plow depth,
       Medium sand ........................................... 0.5 to 0.25               ordinarily to shatter a hardpan or claypan.
       Fine sand ............................................... 0.25 to 0.10        Substratum. The part of the soil below the solum.
       Very fine sand ........................................ 0.10 to 0.05          Subsurface layer. Technically, the E horizon.
       Silt ........................................................ 0.05 to 0.002       Generally refers to a leached horizon lighter in
       Clay .................................................. less than 0.002           color and lower in content of organic matter than
                                                                                         the overlying surface layer.
Solum. The upper part of a soil profile, above the C                                 Summit. The topographically highest position of a
   horizon, in which the processes of soil formation                                     hillslope. It has a nearly level (planar or only
   are active. The solum in soil consists of the A, E,                                   slightly convex) surface.
   and B horizons. Generally, the characteristics of                                 Surface layer. The soil ordinarily moved in tillage, or
156




     its equivalent in uncultivated soil, ranging in depth       to tillage, seedbed preparation, seedling
     from 4 to 10 inches (10 to 25 centimeters).                 emergence, and root penetration.
     Frequently designated as the “plow layer,” or the       Toeslope. The position that forms the gently inclined
     “Ap horizon.”                                               surface at the base of a hillslope. Toeslopes in
Talus. Fragments of rock and other soil material                 profile are commonly gentle and linear and are
     accumulated by gravity at the foot of cliffs or steep       constructional surfaces forming the lower part of a
     slopes.                                                     hillslope continuum that grades to valley or closed-
Taxadjuncts. Soils that cannot be classified in a                depression floors.
     series recognized in the classification system.         Topsoil. The upper part of the soil, which is the
     Such soils are named for a series they strongly             most favorable material for plant growth. It is
     resemble and are designated as taxadjuncts to               ordinarily rich in organic matter and is used to
     that series because they differ in ways too small to        topdress roadbanks, lawns, and land affected by
     be of consequence in interpreting their use and             mining.
     behavior. Soils are recognized as taxadjuncts only      Understory. Any plants in a forest community that
     when one or more of their characteristics are               grow to a height of less than 5 feet.
     slightly outside the range defined for the family of    Upland (geology). Land at a higher elevation, in
     the series for which the soils are named.                   general, than the alluvial plain or stream terrace;
Terminal moraine. A belt of thick glacial drift that             land above the lowlands along streams.
     generally marks the termination of important            Variegation. Refers to patterns of contrasting colors
     glacial advances.                                           assumed to be inherited from the parent material
Terrace. An embankment, or ridge, constructed                    rather than to be the result of poor drainage.
     across sloping soils on the contour or at a slight      Varve. A sedimentary layer or a lamina or sequence of
     angle to the contour. The terrace intercepts                laminae deposited in a body of still water within a
     surface runoff so that water soaks into the soil or         year. Specifically, a thin pair of graded
     flows slowly to a prepared outlet. A terrace in a           glaciolacustrine layers seasonally deposited,
     field generally is built so that the field can be           usually by meltwater streams, in a glacial lake or
     farmed. A terrace intended mainly for drainage              other body of still water in front of a glacier.
     has a deep channel that is maintained in                Weathering. All physical and chemical changes
     permanent sod.                                              produced in rocks or other deposits at or near the
Terrace (geologic). An old alluvial plain, ordinarily flat       earth’s surface by atmospheric agents. These
     or undulating, bordering a river, a lake, or the sea.       changes result in disintegration and
Texture, soil. The relative proportions of sand, silt,           decomposition of the material.
     and clay particles in a mass of soil. The basic         Well graded. Refers to soil material consisting of
     textural classes, in order of increasing proportion         coarse grained particles that are well distributed
     of fine particles, are sand, loamy sand, sandy              over a wide range in size or diameter. Such soil
     loam, loam, silt loam, silt, sandy clay loam, clay          normally can be easily increased in density and
     loam, silty clay loam, sandy clay, silty clay, and          bearing properties by compaction. Contrasts with
     clay. The sand, loamy sand, and sandy loam                  poorly graded soil.
     classes may be further divided by specifying            Wilting point (or permanent wilting point). The
     “coarse,” “fine,” or “very fine.”                           moisture content of soil, on an ovendry basis, at
Thin layer (in tables). Otherwise suitable soil material         which a plant (specifically a sunflower) wilts so
     that is too thin for the specified use.                     much that it does not recover when placed in a
Till plain. An extensive area of nearly level to                 humid, dark chamber.
     undulating soils underlain by glacial till.             Windthrow. The uprooting and tipping over of trees by
Tilth, soil. The physical condition of the soil as related       the wind.
         157




Tables
158                                                                                                        Soil Survey of



                                          Table 1.--Temperature and Precipitation

                                  (Recorded in the period 1971-2000 at Moline, Illinois)

      _______________________________________________________________________________________________________________
                  |                                                         |
                  |                       Temperature                       |             Precipitation
                                                                            |
                  |__________________________________________________________________________________________________
                  |       |       |       |     2 years in        |         |       |2 years in 10|         |
                  |       |       |       |_______________________|
                                              10 will have--                |         will have--
                                                                                    |_____________|         |
         Month    |Average|Average|Average|           |           | Average |Average|      |      | Average |Average
                  | daily | daily |       | Maximum | Minimum |number of|           | Less | More |number of|snowfall
                  |maximum|minimum|       |temperature|temperature| growing |       |than--|than--|days with|
                  |       |       |       | higher    | lower     | degree |        |      |      |0.10 inch|
                  |       |       |       | than--    | than--    | days*   |       |      |      | or more |
      _______________________________________________________________________________________________________________
                  | oF    | oF    | oF    |    oF     |    oF     | Units | In      | In | In |             |   In
                  |       |       |       |           |           |         |       |      |      |         |
       January----| 29.2 | 12.3 | 20.8 |        58    |    -19    |     0   | 1.58 | 0.82| 2.25|         4  |   9.6
                  |       |       |       |           |           |         |       |      |      |         |
       February---| 35.2 | 18.2 | 26.7 |        65    |    -16    |     0   | 1.51 |    .84| 2.11|       3  |   7.1
                  |       |       |       |           |           |         |       |      |      |         |
       March------| 48.0 | 28.9 | 38.5 |        80    |       3   |    30   | 2.92 | 1.35| 4.27|         6  |   4.8
                  |       |       |       |           |           |         |       |      |      |         |
       April------| 61.5 | 39.3 | 50.4 |        87    |      18   |   121   | 3.82 | 2.26| 5.21|         6  |   1.4
                  |       |       |       |           |           |         |       |      |      |         |
       May--------| 73.0 | 50.0 | 61.5 |        92    |      32   |   362   | 4.25 | 2.23| 6.03|         7  |    .0
                  |       |       |       |           |           |         |       |      |      |         |
       June-------| 82.5 | 59.7 | 71.1 |        97    |      43   |   636   | 4.63 | 2.40| 6.58|         7  |    .0
                  |       |       |       |           |           |         |       |      |      |         |
       July-------| 85.9 | 64.5 | 75.2 |        99    |      49   |   784   | 4.03 | 1.94| 5.84|         6  |    .0
                  |       |       |       |           |           |         |       |      |      |         |
       August-----| 83.6 | 62.4 | 73.0 |        98    |      47   |   712   | 4.41 | 1.73| 6.66|         6  |    .0
                  |       |       |       |           |           |         |       |      |      |         |
       September--| 76.2 | 53.4 | 64.8 |        94    |      33   |   446   | 3.16 | 1.29| 4.73|         5  |    .0
                  |       |       |       |           |           |         |       |      |      |         |
       October----| 64.1 | 41.6 | 52.8 |        86    |      23   |   160   | 2.80 | 1.26| 4.11|         5  |    .2
                  |       |       |       |           |           |         |       |      |      |         |
       November---| 47.6 | 30.1 | 38.8 |        74    |       6   |    25   | 2.73 | 1.28| 3.97|         5  |   3.2
                  |       |       |       |           |           |         |       |      |      |         |
       December---| 34.0 | 18.3 | 26.1 |        62    |    -12    |     3   | 2.20 | 1.07| 3.18|         4  |   7.4
                  |       |       |       |           |           |         |       |      |      |         |
       Yearly:    |       |       |       |           |           |         |       |      |      |         |
                  |       |       |       |           |           |         |       |      |      |         |
        Average---| 60.1 | 39.9 | 50.0 |       ---    |    ---    |   ---   |   --- |   ---|   ---|   ---   |   ---
                  |       |       |       |           |           |         |       |      |      |         |
        Extreme---|   104 |   -28 |   --- |    100    |    -22    |   ---   |   --- |   ---|   ---|   ---   |   ---
                  |       |       |       |           |           |         |       |      |      |         |
        Total-----|   --- |   --- |   --- |    ---    |    ---    | 3,279   | 38.04 | 31.60| 44.19|     64  | 33.7
                  |       |       |       |           |           |         |       |      |      |         |
      _______________________________________________________________________________________________________________

          * A growing degree day is a unit of heat available for plant growth. It can be calculated by adding the
      maximum and minimum daily temperatures, dividing the sum by 2, and subtracting the temperature below which
      growth is minimal for the principal crops in the area (50 degrees F).
Rock Island County, Illinois                                                                   159



                                         Table 2.--Freeze Dates in Spring and Fall

                                  (Recorded in the period 1971-2000 at Moline, Illinois)

                               _____________________________________________________________
                                                 |
                                                 |               Temperature
                                                 |__________________________________________
                                  Probability    |             |             |
                                                 |    24 oF    |    28 oF    |    32 oF
                                                 | or lower    | or lower    | or lower
                               _____________________________________________________________
                                                 |             |             |
                                                 |             |             |
                               Last freezing     |             |             |
                                temperature      |             |             |
                                in spring:       |             |             |
                                                 |             |             |
                                 1 year in 10    |             |             |
                                  later than--   | Apr. 14     | Apr. 23     | May     8
                                                 |             |             |
                                 2 years in 10   |             |             |
                                  later than--   | Apr. 10     | Apr. 19     | May     4
                                                 |             |             |
                                 5 years in 10   |             |             |
                                  later than--   | Apr.    2   | Apr. 11     | Apr. 25
                                                 |             |             |
                               First freezing    |             |             |
                                temperature      |             |             |
                                in fall:         |             |             |
                                                 |             |             |
                                 1 year in 10    |             |             |
                                  earlier than-- | Oct. 17     | Oct.    6   | Sept. 26
                                                 |             |             |
                                 2 years in 10   |             |             |
                                  earlier than-- | Oct. 22     | Oct. 11     | Sept. 30
                                                 |             |             |
                                 5 years in 10   |             |             |
                                  earlier than-- | Nov.    1   | Oct. 22     | Oct.    8
                                                 |             |             |
                               _____________________________________________________________




                                                 Table 3.--Growing Season

                                    (Recorded in the period 1971-2000 at Moline,
                                         Illinois)

                                    __________________________________________________
                                                  |
                                                  |    Daily minimum temperature
                                                  |      during growing season
                                                  |___________________________________
                                     Probability |             |           |
                                                  |   Higher   | Higher    | Higher
                                                  |    than    |   than    |   than
                                                  |    24 oF   |   28 oF   |   32 oF
                                    __________________________________________________
                                                  |    Days    |   Days    |   Days
                                                  |            |           |
                                    9 years in 10 |    194     |   172     |   146
                                                  |            |           |
                                    8 years in 10 |    200     |   179     |   153
                                                  |            |           |
                                    5 years in 10 |    212     |   193     |   165
                                                  |            |           |
                                    2 years in 10 |    224     |   207     |   177
                                                  |            |           |
                                    1 year in 10 |     230     |   215     |   184
                                                  |            |           |
                                    __________________________________________________
160                                                                                               Soil Survey of



                                  Table 4.--Classification of the Soils

      (An asterisk in the first column indicates a taxadjunct to the series. See text for a
           description of those characteristics that are outside the range of the series)

      ______________________________________________________________________________________________
                        |
          Soil name     |                     Family or higher taxonomic class
                        |
      ______________________________________________________________________________________________
                        |
       Ambraw-----------|Fine-loamy, mixed, superactive, mesic Fluvaquentic Endoaquolls
       Atlas------------|Fine, smectitic, mesic Aeric Chromic Vertic Epiaqualfs
       Atterberry-------|Fine-silty, mixed, superactive, mesic Udollic Endoaqualfs
       Biggsville-------|Fine-silty, mixed, superactive, mesic Typic Hapludolls
       Birds------------|Fine-silty, mixed, superactive, nonacid, mesic Typic Fluvaquents
       Bold-------------|Coarse-silty, mixed, superactive, calcareous, mesic Typic Udorthents
       Buckhart---------|Fine-silty, mixed, superactive, mesic Oxyaquic Argiudolls
       Burkhardt--------|Sandy, mixed, mesic Typic Hapludolls
       Calco------------|Fine-silty, mixed, superactive, calcareous, mesic Cumulic Endoaquolls
       Chute------------|Mixed, mesic Typic Udipsamments
       Coatsburg--------|Fine, smectitic, mesic Vertic Argiaquolls
       Coffeen----------|Coarse-silty, mixed, superactive, mesic Fluvaquentic Hapludolls
       Coloma-----------|Mixed, mesic Lamellic Udipsamments
       Coyne------------|Coarse-loamy, mixed, active, mesic Typic Argiudolls
       Denny------------|Fine, smectitic, mesic Mollic Albaqualfs
       Dickinson--------|Coarse-loamy, mixed, superactive, mesic Typic Hapludolls
       Dorchester-------|Fine-silty, mixed, superactive, calcareous, mesic Typic Udifluvents
      *Elkhart----------|Fine-silty, mixed, superactive, mesic Typic Argiudolls
       Fayette----------|Fine-silty, mixed, superactive, mesic Typic Hapludalfs
       Fluvaquents------|Fine-silty, mixed, active, nonacid, mesic Typic Fluvaquents
       Greenbush--------|Fine-silty, mixed, superactive, mesic Mollic Hapludalfs
       Hickory----------|Fine-loamy, mixed, active, mesic Typic Hapludalfs
       Hoopeston--------|Coarse-loamy, mixed, superactive, mesic Aquic Hapludolls
       Joslin-----------|Fine-loamy, mixed, superactive, mesic Typic Argiudolls
       Joy--------------|Fine-silty, mixed, superactive, mesic Aquic Hapludolls
       Landes-----------|Coarse-loamy, mixed, superactive, mesic Fluventic Hapludolls
       Lawler-----------|Fine-loamy over sandy or sandy-skeletal, mixed, superactive, mesic Aquic
                        | Hapludolls
       Lawson-----------|Fine-silty, mixed, superactive, mesic Aquic Cumulic Hapludolls
       Marseilles-------|Fine-silty, mixed, active, mesic Typic Hapludalfs
       Martinsville-----|Fine-loamy, mixed, active, mesic Typic Hapludalfs
       Millington-------|Fine-loamy, mixed, superactive, calcareous, mesic Cumulic Endoaquolls
       Millsdale--------|Fine, mixed, active, mesic Typic Argiaquolls
       Moline-----------|Fine, smectitic, mesic Vertic Endoaquolls
       Muscatune--------|Fine-silty, mixed, superactive, mesic Aquic Argiudolls
       Niota------------|Fine, mixed, superactive, mesic Vertic Albaqualfs
       Oakville---------|Mixed, mesic Typic Udipsamments
       Orion------------|Coarse-silty, mixed, superactive, nonacid, mesic Aquic Udifluvents
       Orthents---------|Fine-loamy, mixed, active, nonacid, mesic Typic Udorthents
      *Osco-------------|Fine-silty, mixed, superactive, mesic Typic Argiudolls
       Otter------------|Fine-silty, mixed, superactive, mesic Cumulic Endoaquolls
       Psamments--------|Mixed, mesic Udipsamments
       Raddle-----------|Fine-silty, mixed, superactive, mesic Typic Hapludolls
       Radford----------|Fine-silty, mixed, superactive, mesic Fluvaquentic Hapludolls
       Rozetta----------|Fine-silty, mixed, superactive, mesic Typic Hapludalfs
       Sable------------|Fine-silty, mixed, superactive, mesic Typic Endoaquolls
       Saude------------|Coarse-loamy over sandy or sandy-skeletal, mixed, superactive, mesic
                        | Typic Hapludolls
       Sawmill----------|Fine-silty, mixed, superactive, mesic Cumulic Endoaquolls
       Seaton-----------|Fine-silty, mixed, superactive, mesic Typic Hapludalfs
       Sparta-----------|Sandy, mixed, mesic Entic Hapludolls
       Strawn-----------|Fine-loamy, mixed, active, mesic Typic Hapludalfs
       Stronghurst------|Fine-silty, mixed, superactive, mesic Aeric Endoaqualfs
       Sylvan-----------|Fine-silty, mixed, superactive, mesic Typic Hapludalfs
       Tell-------------|Fine-silty over sandy or sandy-skeletal, mixed, superactive, mesic
                        | Typic Hapludalfs
       Thebes-----------|Fine-silty, mixed, superactive, mesic Typic Hapludalfs
       Timula-----------|Coarse-silty, mixed, superactive, mesic Typic Eutrudepts
       Titus------------|Fine, smectitic, mesic Vertic Endoaquolls
                        |
Rock Island County, Illinois                                                                                  161



                                    Table 4.--Classification of the Soils--Continued
             ______________________________________________________________________________________________
                               |
                 Soil name     |                     Family or higher taxonomic class
                               |
             ______________________________________________________________________________________________
                               |
              Velma------------|Fine-loamy, mixed, superactive, mesic Typic Argiudolls
              Wabash-----------|Fine, smectitic, mesic Cumulic Vertic Endoaquolls
              Waukee-----------|Fine-loamy over sandy or sandy-skeletal, mixed, superactive, mesic
                               | Typic Hapludolls
                               |
             ______________________________________________________________________________________________
162                                                                                                     Soil Survey of



                                Table 5.--Acreage and Proportionate Extent of the Soils
______________________________________________________________________________________________________________________
       |                                                                                        |             |
 Map   |                                       Soil name                                        |   Acres     |Percent
symbol |                                                                                        |             |
       |                                                                                        |             |
______________________________________________________________________________________________________________________
       |                                                                                        |             |
8D2    |Hickory silt loam, 10 to 18 percent slopes, eroded--------------------------------------|         511 |    0.2
8D3    |Hickory clay loam, 10 to 18 percent slopes, severely eroded-----------------------------|      1,153 |     0.4
8F     |Hickory silt loam, 18 to 35 percent slopes----------------------------------------------|      3,290 |     1.1
8F3    |Hickory clay loam, 18 to 35 percent slopes, severely eroded-----------------------------|      1,305 |     0.5
19C3   |Sylvan silty clay loam, 5 to 10 percent slopes, severely eroded-------------------------|      2,479 |     0.9
19D    |Sylvan silt loam, 10 to 18 percent slopes-----------------------------------------------|      1,474 |     0.5
19D3   |Sylvan silty clay loam, 10 to 18 percent slopes, severely eroded------------------------|      8,662 |     3.0
19F    |Sylvan silt loam, 18 to 35 percent slopes-----------------------------------------------|      4,586 |     1.6
19F3   |Sylvan silty clay loam, 18 to 35 percent slopes, severely eroded------------------------|      1,720 |     0.6
45A    |Denny silt loam, 0 to 2 percent slopes--------------------------------------------------|         290 |    0.1
51A    |Muscatune silt loam, 0 to 2 percent slopes----------------------------------------------|     14,387 |     5.0
61A    |Atterberry silt loam, 0 to 2 percent slopes---------------------------------------------|      2,924 |     1.0
68A    |Sable silty clay loam, 0 to 2 percent slopes--------------------------------------------|      1,554 |     0.5
86B    |Osco silt loam, 2 to 5 percent slopes---------------------------------------------------|      7,336 |     2.5
86C2   |Osco silt loam, 5 to 10 percent slopes, eroded------------------------------------------|      5,193 |     1.8
87A    |Dickinson sandy loam, 0 to 2 percent slopes---------------------------------------------|      3,605 |     1.2
87C2   |Dickinson sandy loam, 5 to 10 percent slopes, eroded------------------------------------|         171 |     *
88A    |Sparta loamy sand, 0 to 2 percent slopes------------------------------------------------|      7,349 |     2.5
172A   |Hoopeston sandy loam, 0 to 2 percent slopes---------------------------------------------|         397 |    0.1
212B   |Thebes silt loam, 2 to 5 percent slopes-------------------------------------------------|         651 |    0.2
250D   |Velma silt loam, 10 to 18 percent slopes------------------------------------------------|         318 |    0.1
261A   |Niota silt loam, 0 to 2 percent slopes--------------------------------------------------|      1,179 |     0.4
274B   |Seaton silt loam, 2 to 5 percent slopes-------------------------------------------------|      1,038 |     0.4
274B2 |Seaton silt loam, 2 to 5 percent slopes, eroded-----------------------------------------|       2,102 |     0.7
274C2 |Seaton silt loam, 5 to 10 percent slopes, eroded----------------------------------------|       2,371 |     0.8
274D2 |Seaton silt loam, 10 to 18 percent slopes, eroded---------------------------------------|          993 |    0.3
275A   |Joy silt loam, 0 to 2 percent slopes----------------------------------------------------|         757 |    0.3
278A   |Stronghurst silt loam, 0 to 2 percent slopes--------------------------------------------|      2,667 |     0.9
279A   |Rozetta silt loam, 0 to 2 percent slopes------------------------------------------------|      4,627 |     1.6
279B   |Rozetta silt loam, 2 to 5 percent slopes------------------------------------------------|         190 |     *
280B   |Fayette silt loam, 2 to 5 percent slopes------------------------------------------------|     28,659 |     9.9
280B2 |Fayette silt loam, 2 to 5 percent slopes, eroded----------------------------------------|       3,137 |     1.1
280C2 |Fayette silt loam, 5 to 10 percent slopes, eroded---------------------------------------|       4,432 |     1.5
280C3 |Fayette silty clay loam, 5 to 10 percent slopes, severely eroded------------------------|          952 |    0.3
317A   |Millsdale silty clay loam, 0 to 2 percent slopes----------------------------------------|         498 |    0.2
430A   |Raddle silt loam, 0 to 2 percent slopes-------------------------------------------------|      3,526 |     1.2
430B   |Raddle silt loam, 2 to 5 percent slopes-------------------------------------------------|      2,393 |     0.8
525A   |Joslin loam, bedrock substratum, 0 to 2 percent slopes----------------------------------|         518 |    0.2
567C2 |Elkhart silt loam, 5 to 10 percent slopes, eroded---------------------------------------|       1,193 |     0.4
567D2 |Elkhart silt loam, 10 to 18 percent slopes, eroded--------------------------------------|          729 |    0.3
570B   |Martinsville silt loam, 2 to 5 percent slopes-------------------------------------------|         738 |    0.3
570C3 |Martinsville clay loam, 5 to 10 percent slopes, severely eroded-------------------------|          287 |     *
570D3 |Martinsville clay loam, 10 to 18 percent slopes, severely eroded------------------------|          440 |    0.2
647A   |Lawler loam, 0 to 2 percent slopes------------------------------------------------------|         599 |    0.2
671A   |Biggsville silt loam, 0 to 2 percent slopes---------------------------------------------|         983 |    0.3
671B   |Biggsville silt loam, 2 to 5 percent slopes---------------------------------------------|      4,365 |     1.5
675A   |Greenbush silt loam, 0 to 2 percent slopes----------------------------------------------|      2,232 |     0.8
675B   |Greenbush silt loam, 2 to 5 percent slopes----------------------------------------------|      5,703 |     2.0
689B   |Coloma sand, 1 to 7 percent slopes------------------------------------------------------|         276 |     *
689D   |Coloma sand, 7 to 15 percent slopes-----------------------------------------------------|         128 |     *
705A   |Buckhart silt loam, 0 to 2 percent slopes-----------------------------------------------|      1,195 |     0.4
727A   |Waukee loam, 0 to 2 percent slopes------------------------------------------------------|      1,618 |     0.6
741F   |Oakville fine sand, 20 to 30 percent slopes---------------------------------------------|         248 |     *
763A   |Joslin silt loam, 0 to 2 percent slopes-------------------------------------------------|      1,575 |     0.5
763B   |Joslin silt loam, 2 to 5 percent slopes-------------------------------------------------|         328 |    0.1
764A   |Coyne fine sandy loam, 0 to 2 percent slopes--------------------------------------------|      4,339 |     1.5
764C   |Coyne fine sandy loam, 5 to 10 percent slopes-------------------------------------------|         483 |    0.2
774A   |Saude loam, 0 to 2 percent slopes-------------------------------------------------------|         355 |    0.1
800C   |Psamments, sloping----------------------------------------------------------------------|         418 |    0.1
802B   |Orthents, loamy, undulating-------------------------------------------------------------|      8,190 |     2.8
864    |Pits, quarries--------------------------------------------------------------------------|         418 |    0.1
865    |Pits, gravel----------------------------------------------------------------------------|         156 |     *
       |                                                                                        |             |

      See footnote at end of table.
Rock Island County, Illinois                                                                                       163



                          Table 5.--Acreage and Proportionate Extent of the Soils--Continued
______________________________________________________________________________________________________________________
       |                                                                                        |             |
  Map  |                                       Soil name                                        |   Acres     |Percent
symbol |                                                                                        |             |
       |                                                                                        |             |
______________________________________________________________________________________________________________________
       |                                                                                        |             |
898F3 |Hickory-Sylvan complex, 18 to 35 percent slopes, severely eroded------------------------|       1,338 |     0.5
898G   |Hickory-Sylvan silt loams, 35 to 60 percent slopes--------------------------------------|      8,202 |     2.8
913D2 |Marseilles-Hickory silt loams, 10 to 18 percent slopes, eroded--------------------------|          583 |    0.2
913F   |Marseilles-Hickory silt loams, 18 to 35 percent slopes----------------------------------|      2,417 |     0.8
913G   |Marseilles-Hickory silt loams, 35 to 60 percent slopes----------------------------------|      2,747 |     1.0
917C2 |Oakville-Tell complex, 5 to 10 percent slopes, eroded-----------------------------------|       1,214 |     0.4
917D2 |Oakville-Tell complex, 10 to 18 percent slopes, eroded----------------------------------|       1,075 |     0.4
943D2 |Seaton-Timula silt loams, 10 to 18 percent slopes, eroded-------------------------------|       1,931 |     0.7
943F2 |Seaton-Timula silt loams, 18 to 35 percent slopes, eroded-------------------------------|       2,729 |     0.9
944D2 |Velma-Coatsburg silt loams, 10 to 18 percent slopes, eroded-----------------------------|          288 |     *
946D3 |Hickory-Atlas complex, 10 to 18 percent slopes, severely eroded-------------------------|       1,643 |     0.6
946F3 |Hickory-Atlas complex, 18 to 35 percent slopes, severely eroded-------------------------|       1,452 |     0.5
959G   |Strawn-Chute complex, 18 to 60 percent slopes-------------------------------------------|         950 |    0.3
960D2 |Hickory-Sylvan-Fayette silt loams, 10 to 18 percent slopes, eroded----------------------|       5,146 |     1.8
960D3 |Hickory-Sylvan-Fayette complex, 10 to 18 percent slopes, severely eroded----------------|       1,589 |     0.5
960F   |Hickory-Sylvan-Fayette silt loams, 18 to 30 percent slopes------------------------------|     11,782 |     4.1
961A   |Burkhardt-Saude complex, 0 to 2 percent slopes------------------------------------------|         771 |    0.3
962F   |Sylvan-Bold silt loams, 18 to 35 percent slopes-----------------------------------------|      1,325 |     0.5
1076A |Otter silt loam, undrained, 0 to 2 percent slopes, frequently flooded-------------------|       1,205 |     0.4
1082A |Millington silt loam, undrained, 0 to 2 percent slopes, frequently flooded--------------|          537 |    0.2
1107A |Sawmill silty clay loam, undrained, 0 to 2 percent slopes, frequently flooded-----------|       1,404 |     0.5
1334A |Birds silt loam, undrained, 0 to 2 percent slopes, frequently flooded-------------------|           18 |     *
1400A |Calco silty clay loam, undrained, 0 to 2 percent slopes, frequently flooded-------------|          286 |     *
1654A |Moline silty clay, undrained, 0 to 2 percent slopes, frequently flooded-----------------|          573 |    0.2
3074A |Radford silt loam, 0 to 2 percent slopes, frequently flooded----------------------------|       4,669 |     1.6
3076A |Otter silt loam, 0 to 2 percent slopes, frequently flooded------------------------------|       2,440 |     0.8
3082A |Millington silt loam, 0 to 2 percent slopes, frequently flooded-------------------------|       1,489 |     0.5
3083A |Wabash silty clay, 0 to 2 percent slopes, frequently flooded----------------------------|          395 |    0.1
3107A |Sawmill silty clay loam, 0 to 2 percent slopes, frequently flooded----------------------|       7,112 |     2.5
3239A |Dorchester silt loam, 0 to 2 percent slopes, frequently flooded-------------------------|       1,351 |     0.5
3400A |Calco silty clay loam, 0 to 2 percent slopes, frequently flooded------------------------|       1,277 |     0.4
3415A |Orion silt loam, 0 to 2 percent slopes, frequently flooded------------------------------|       9,326 |     3.2
3428A |Coffeen silt loam, 0 to 2 percent slopes, frequently flooded----------------------------|          662 |    0.2
3451A |Lawson silt loam, 0 to 2 percent slopes, frequently flooded-----------------------------|       4,487 |     1.6
3646L |Fluvaquents, loamy, 0 to 2 percent slopes, frequently flooded, long duration------------|       5,083 |     1.8
7076A |Otter silt loam, 0 to 2 percent slopes, rarely flooded----------------------------------|          343 |    0.1
7083A |Wabash silty clay, 0 to 2 percent slopes, rarely flooded--------------------------------|          565 |    0.2
7107A |Sawmill silty clay loam, 0 to 2 percent slopes, rarely flooded--------------------------|       4,137 |     1.4
7239A |Dorchester silt loam, 0 to 2 percent slopes, rarely flooded-----------------------------|          397 |    0.1
7304A |Landes fine sandy loam, 0 to 2 percent slopes, rarely flooded---------------------------|          376 |    0.1
7415A |Orion silt loam, 0 to 2 percent slopes, rarely flooded----------------------------------|       1,520 |     0.5
7428A |Coffeen silt loam, 0 to 2 percent slopes, rarely flooded--------------------------------|       5,896 |     2.0
7451A |Lawson silt loam, 0 to 2 percent slopes, rarely flooded---------------------------------|          501 |    0.2
7654A |Moline silty clay, 0 to 2 percent slopes, rarely flooded--------------------------------|          980 |    0.3
8107+ |Sawmill silt loam, 0 to 2 percent slopes, occasionally flooded, overwash----------------|          729 |    0.3
8302A |Ambraw loam, 0 to 2 percent slopes, occasionally flooded--------------------------------|          161 |     *
8400A |Calco silty clay loam, 0 to 2 percent slopes, occasionally flooded----------------------|       1,167 |     0.4
8404A |Titus silty clay loam, 0 to 2 percent slopes, occasionally flooded----------------------|           48 |     *
M-W    |Miscellaneous water---------------------------------------------------------------------|          97 |     *
W      |Water-----------------------------------------------------------------------------------|     16,107 |     5.6
       |                                                                                        |____________|________
       |     Total------------------------------------------------------------------------------|    288,910 | 100.0
       |                                                                                        |             |
______________________________________________________________________________________________________________________

     * Less than 0.1 percent.
164                                                                                              Soil Survey of



                   Table 6.--Land Capability and Yields per Acre of Crops and Pasture

      (Yields are those that can be expected under a high level of management. They are for
           nonirrigated areas. Absence of a yield indicates that the soil is not suited to the
           crop or the crop generally is not grown on the soil)

      ____________________________________________________________________________________________
                    |          |         |          |         |         |            |
        Map symbol | Land      | Corn    | Soybeans | Oats    | Winter |Grass-legume|Grass-legume
      and soil name |capability|         |          |         | wheat   |    hay     | pasture
                    |          |         |          |         |         |            |
      ____________________________________________________________________________________________
                    |          |   Bu    |    Bu    |   Bu    |   Bu    |    Tons    |    AUM*
                    |          |         |          |         |         |            |
      8D2:          |          |         |          |         |         |            |
       Hickory------|     3e   |    72   |     23   |    50   |    26   |     2.7    |    4.5
                    |          |         |          |         |         |            |
      8D3:          |          |         |          |         |         |            |
       Hickory------|     4e   |    66   |     22   |    46   |    24   |     2.5    |    4.2
                    |          |         |          |         |         |            |
      8F:           |          |         |          |         |         |            |
       Hickory------|     6e   |   ---   |    ---   |   ---   |   ---   |     2.4    |    4.0
                    |          |         |          |         |         |            |
      8F3:          |          |         |          |         |         |            |
       Hickory------|     6e   |   ---   |    ---   |   ---   |   ---   |     2.1    |    3.5
                    |          |         |          |         |         |            |
      19C3:         |          |         |          |         |         |            |
       Sylvan-------|     4e   |    97   |     30   |    57   |    46   |     4.4    |    7.3
                    |          |         |          |         |         |            |
      19D:          |          |         |          |         |         |            |
       Sylvan-------|     3e   |   104   |     33   |    61   |    49   |     4.7    |    7.8
                    |          |         |          |         |         |            |
      19D3:         |          |         |          |         |         |            |
       Sylvan-------|     4e   |    93   |     29   |    55   |    44   |     4.2    |    6.9
                    |          |         |          |         |         |            |
      19F:          |          |         |          |         |         |            |
       Sylvan-------|     6e   |   ---   |    ---   |   ---   |   ---   |     4.0    |    6.7
                    |          |         |          |         |         |            |
      19F3:         |          |         |          |         |         |            |
       Sylvan-------|     6e   |   ---   |    ---   |   ---   |   ---   |     3.5    |    5.8
                    |          |         |          |         |         |            |
      45A:          |          |         |          |         |         |            |
       Denny--------|     3w   |   113   |     37   |    62   |    47   |     ---    |    ---
                    |          |         |          |         |         |            |
      51A:          |          |         |          |         |         |            |
       Muscatune----|     1    |   167   |     51   |    95   |    64   |     6.2    |   10.3
                    |          |         |          |         |         |            |
      61A:          |          |         |          |         |         |            |
       Atterberry---|     1    |   149   |     44   |    85   |    60   |     5.6    |    9.3
                    |          |         |          |         |         |            |
      68A:          |          |         |          |         |         |            |
       Sable--------|     2w   |   156   |     51   |    85   |    61   |     ---    |    ---
                    |          |         |          |         |         |            |
      86B:          |          |         |          |         |         |            |
       Osco---------|     2e   |   153   |     46   |    88   |    61   |     5.8    |    9.7
                    |          |         |          |         |         |            |
      86C2:         |          |         |          |         |         |            |
       Osco---------|     3e   |   146   |     43   |    84   |    58   |     5.5    |    9.2
                    |          |         |          |         |         |            |
      87A:          |          |         |          |         |         |            |
       Dickinson----|     2s   |    99   |     37   |    77   |    45   |     3.9    |    6.5
                    |          |         |          |         |         |            |
      87C2:         |          |         |          |         |         |            |
       Dickinson----|     3e   |    93   |     34   |    72   |    42   |     3.7    |    6.1
                    |          |         |          |         |         |            |
      88A:          |          |         |          |         |         |            |
       Sparta-------|     4s   |    85   |     29   |    53   |    37   |     3.3    |    5.5
                    |          |         |          |         |         |            |

          See footnote at end of table.
Rock Island County, Illinois                                                                                 165



                      Table 6.--Land Capability and Yields per Acre of Crops and Pasture--Continued
              ____________________________________________________________________________________________
                            |          |         |          |         |         |            |
                Map symbol | Land      | Corn    | Soybeans | Oats    | Winter |Grass-legume|Grass-legume
              and soil name |capability|         |          |         | wheat   |    hay     | pasture
                            |          |         |          |         |         |            |
              ____________________________________________________________________________________________
                            |          |   Bu    |    Bu    |   Bu    |   Bu    |    Tons    |    AUM*
                            |          |         |          |         |         |            |
              172A:         |          |         |          |         |         |            |
               Hoopeston----|     2s   |   105   |     33   |    70   |    47   |     4.1    |    6.8
                            |          |         |          |         |         |            |
              212B:         |          |         |          |         |         |            |
               Thebes-------|     2e   |    99   |     35   |    72   |    46   |     4.0    |    6.6
                            |          |         |          |         |         |            |
              250D:         |          |         |          |         |         |            |
               Velma--------|     3e   |   110   |     36   |    67   |    47   |     4.3    |    7.1
                            |          |         |          |         |         |            |
              261A:         |          |         |          |         |         |            |
               Niota--------|     2w   |    86   |     30   |    53   |    39   |     3.3    |    5.5
                            |          |         |          |         |         |            |
              274B:         |          |         |          |         |         |            |
               Seaton-------|     2e   |   117   |     35   |    68   |    49   |     4.7    |    7.9
                            |          |         |          |         |         |            |
              274B2:        |          |         |          |         |         |            |
               Seaton-------|     2e   |   114   |     34   |    66   |    47   |     4.6    |    7.7
                            |          |         |          |         |         |            |
              274C2:        |          |         |          |         |         |            |
               Seaton-------|     3e   |   110   |     33   |    65   |    46   |     4.5    |    7.5
                            |          |         |          |         |         |            |
              274D2:        |          |         |          |         |         |            |
               Seaton-------|     4e   |   106   |     32   |    62   |    44   |     4.3    |    7.2
                            |          |         |          |         |         |            |
              275A:         |          |         |          |         |         |            |
               Joy----------|     1    |   161   |     48   |    92   |    63   |     6.1    |   10.2
                            |          |         |          |         |         |            |
              278A:         |          |         |          |         |         |            |
               Stronghurst--|     2w   |   138   |     42   |    76   |    55   |     5.3    |    8.8
                            |          |         |          |         |         |            |
              279A:         |          |         |          |         |         |            |
               Rozetta------|     1    |   131   |     40   |    73   |    54   |     5.2    |    8.6
                            |          |         |          |         |         |            |
              279B:         |          |         |          |         |         |            |
               Rozetta------|     2e   |   130   |     40   |    72   |    53   |     5.1    |    8.6
                            |          |         |          |         |         |            |
              280B:         |          |         |          |         |         |            |
               Fayette------|     2e   |   128   |     39   |    72   |    52   |     5.1    |    8.6
                            |          |         |          |         |         |            |
              280B2:        |          |         |          |         |         |            |
               Fayette------|     2e   |   124   |     37   |    70   |    51   |     5.0    |    8.3
                            |          |         |          |         |         |            |
              280C2:        |          |         |          |         |         |            |
               Fayette------|     3e   |   121   |     37   |    69   |    50   |     4.9    |    8.1
                            |          |         |          |         |         |            |
              280C3:        |          |         |          |         |         |            |
               Fayette------|     4e   |   112   |     34   |    64   |    46   |     4.5    |    7.5
                            |          |         |          |         |         |            |
              317A:         |          |         |          |         |         |            |
               Millsdale----|     3w   |   113   |     41   |    65   |    47   |     4.4    |    7.3
                            |          |         |          |         |         |            |
              430A:         |          |         |          |         |         |            |
               Raddle-------|     1    |   149   |     45   |    83   |    59   |     5.8    |    9.7
                            |          |         |          |         |         |            |
              430B:         |          |         |          |         |         |            |
               Raddle-------|     2e   |   148   |     45   |    82   |    58   |     5.7    |    9.6
                            |          |         |          |         |         |            |
              525A:         |          |         |          |         |         |            |
               Joslin-------|     1    |   135   |     43   |    80   |    55   |     5.1    |    8.5
                            |          |         |          |         |         |            |

                  See footnote at end of table.
166                                                                                              Soil Survey of



              Table 6.--Land Capability and Yields per Acre of Crops and Pasture--Continued
      ____________________________________________________________________________________________
                    |          |         |          |         |         |            |
        Map symbol | Land      | Corn    | Soybeans | Oats    | Winter |Grass-legume|Grass-legume
      and soil name |capability|         |          |         | wheat   |    hay     | pasture
                    |          |         |          |         |         |            |
      ____________________________________________________________________________________________
                    |          |   Bu    |    Bu    |   Bu    |   Bu    |    Tons    |    AUM*
                    |          |         |          |         |         |            |
      567C2:        |          |         |          |         |         |            |
       Elkhart------|     3e   |   124   |     37   |    69   |    50   |     4.8    |    8.0
                    |          |         |          |         |         |            |
      567D2:        |          |         |          |         |         |            |
       Elkhart------|     3e   |   119   |     35   |    66   |    48   |     4.6    |    7.7
                    |          |         |          |         |         |            |
      570B:         |          |         |          |         |         |            |
       Martinsville |     2e   |   120   |     37   |    65   |    50   |     4.8    |    7.9
                    |          |         |          |         |         |            |
      570C3:        |          |         |          |         |         |            |
       Martinsville |     4e   |   105   |     32   |    57   |    44   |     4.2    |    7.0
                    |          |         |          |         |         |            |
      570D3:        |          |         |          |         |         |            |
       Martinsville |     4e   |   100   |     31   |    55   |    42   |     4.0    |    6.6
                    |          |         |          |         |         |            |
      647A:         |          |         |          |         |         |            |
       Lawler-------|     2s   |   115   |     39   |    61   |    44   |     5.0    |    8.3
                    |          |         |          |         |         |            |
      671A:         |          |         |          |         |         |            |
       Biggsville---|     1    |   150   |     45   |    88   |    61   |     5.6    |    9.3
                    |          |         |          |         |         |            |
      671B:         |          |         |          |         |         |            |
       Biggsville---|     2e   |   149   |     45   |    87   |    60   |     5.5    |    9.2
                    |          |         |          |         |         |            |
      675A:         |          |         |          |         |         |            |
       Greenbush----|     1    |   148   |     43   |    83   |    59   |     5.6    |    9.3
                    |          |         |          |         |         |            |
      675B:         |          |         |          |         |         |            |
       Greenbush----|     2e   |   147   |     42   |    82   |    57   |     5.5    |    9.2
                    |          |         |          |         |         |            |
      689B:         |          |         |          |         |         |            |
       Coloma-------|     4s   |    57   |     40   |    20   |    28   |     2.4    |    4.0
                    |          |         |          |         |         |            |
      689D:         |          |         |          |         |         |            |
       Coloma-------|     6s   |   ---   |    ---   |   ---   |   ---   |     ---    |    ---
                    |          |         |          |         |         |            |
      705A:         |          |         |          |         |         |            |
       Buckhart-----|     1    |   158   |     48   |    90   |    63   |     6.0    |    9.9
                    |          |         |          |         |         |            |
      727A:         |          |         |          |         |         |            |
       Waukee-------|     2s   |   103   |     35   |    66   |    46   |     4.2    |    7.0
                    |          |         |          |         |         |            |
      741F:         |          |         |          |         |         |            |
       Oakville-----|     7s   |   ---   |    ---   |   ---   |   ---   |     ---    |    ---
                    |          |         |          |         |         |            |
      763A:         |          |         |          |         |         |            |
       Joslin-------|     1    |   135   |     43   |    80   |    55   |     5.1    |    8.5
                    |          |         |          |         |         |            |
      763B:         |          |         |          |         |         |            |
       Joslin-------|     2e   |   134   |     43   |    79   |    54   |     5.0    |    8.4
                    |          |         |          |         |         |            |
      764A:         |          |         |          |         |         |            |
       Coyne--------|     2s   |   101   |     35   |    67   |    47   |     3.8    |    6.3
                    |          |         |          |         |         |            |
      764C:         |          |         |          |         |         |            |
       Coyne--------|     3e   |    98   |     34   |    65   |    46   |     ---    |    ---
                    |          |         |          |         |         |            |
      774A:         |          |         |          |         |         |            |
       Saude--------|     2s   |   103   |     35   |    66   |    46   |     4.2    |    7.0
                    |          |         |          |         |         |            |

          See footnote at end of table.
Rock Island County, Illinois                                                                                 167



                      Table 6.--Land Capability and Yields per Acre of Crops and Pasture--Continued
              ____________________________________________________________________________________________
                            |          |         |          |         |         |            |
                Map symbol | Land      | Corn    | Soybeans | Oats    | Winter |Grass-legume|Grass-legume
              and soil name |capability|         |          |         | wheat   |    hay     | pasture
                            |          |         |          |         |         |            |
              ____________________________________________________________________________________________
                            |          |   Bu    |    Bu    |   Bu    |   Bu    |    Tons    |    AUM*
                            |          |         |          |         |         |            |
              800C.         |          |         |          |         |         |            |
               Psamments    |          |         |          |         |         |            |
                            |          |         |          |         |         |            |
              802B:         |          |         |          |         |         |            |
               Orthents-----|     2e   |   ---   |    ---   |   ---   |   ---   |     ---    |    ---
                            |          |         |          |         |         |            |
              898F3---------|          |   ---   |    ---   |   ---   |   ---   |     2.6    |    4.4
               Hickory------|     6e   |         |          |         |         |            |
               Sylvan-------|     6e   |         |          |         |         |            |
                            |          |         |          |         |         |            |
              898G----------|          |   ---   |    ---   |   ---   |   ---   |     ---    |    ---
               Hickory------|     7e   |         |          |         |         |            |
               Sylvan-------|     7e   |         |          |         |         |            |
                            |          |         |          |         |         |            |
              913D2---------|          |    82   |     27   |    53   |    33   |     3.3    |    5.5
               Marseilles---|     4e   |         |          |         |         |            |
               Hickory------|     3e   |         |          |         |         |            |
                            |          |         |          |         |         |            |
              913F----------|          |   ---   |    ---   |   ---   |   ---   |     ---    |    4.8
               Marseilles---|     7e   |         |          |         |         |            |
               Hickory------|     6e   |         |          |         |         |            |
                            |          |         |          |         |         |            |
              913G----------|          |   ---   |    ---   |   ---   |   ---   |     ---    |    ---
               Marseilles---|     7e   |         |          |         |         |            |
               Hickory------|     7e   |         |          |         |         |            |
                            |          |         |          |         |         |            |
              917C2---------|          |   ---   |    ---   |   ---   |   ---   |     3.2    |    5.3
               Oakville-----|     6s   |         |          |         |         |            |
               Tell---------|     3e   |         |          |         |         |            |
                            |          |         |          |         |         |            |
              917D2---------|          |   ---   |    ---   |   ---   |   ---   |     3.1    |    5.1
               Oakville-----|     6s   |         |          |         |         |            |
               Tell---------|     4e   |         |          |         |         |            |
                            |          |         |          |         |         |            |
              943D2---------|          |   102   |     32   |    60   |    43   |     4.1    |    6.9
               Seaton-------|     3e   |         |          |         |         |            |
               Timula-------|     3e   |         |          |         |         |            |
                            |          |         |          |         |         |            |
              943F2---------|          |   ---   |    ---   |   ---   |   ---   |     3.6    |    6.0
               Seaton-------|     6e   |         |          |         |         |            |
               Timula-------|     6e   |         |          |         |         |            |
                            |          |         |          |         |         |            |
              944D2---------|          |    91   |     30   |    54   |    37   |     3.6    |    6.0
               Velma--------|     3e   |         |          |         |         |            |
               Coatsburg----|     4e   |         |          |         |         |            |
                            |          |         |          |         |         |            |
              946D3---------|          |   ---   |    ---   |   ---   |   ---   |     2.2    |    3.9
               Hickory------|     4e   |         |          |         |         |            |
               Atlas--------|     6e   |         |          |         |         |            |
                            |          |         |          |         |         |            |
              946F3---------|          |   ---   |    ---   |   ---   |   ---   |     1.5    |    2.6
               Hickory------|     6e   |         |          |         |         |            |
               Atlas--------|     6e   |         |          |         |         |            |
                            |          |         |          |         |         |            |
              959G----------|          |   ---   |    ---   |   ---   |   ---   |     ---    |    ---
               Strawn-------|     7e   |         |          |         |         |            |
               Chute--------|     7s   |         |          |         |         |            |
                            |          |         |          |         |         |            |

                  See footnote at end of table.
168                                                                                              Soil Survey of



              Table 6.--Land Capability and Yields per Acre of Crops and Pasture--Continued
      ____________________________________________________________________________________________
                    |          |         |          |         |         |            |
        Map symbol | Land      | Corn    | Soybeans | Oats    | Winter |Grass-legume|Grass-legume
      and soil name |capability|         |          |         | wheat   |    hay     | pasture
                    |          |         |          |         |         |            |
      ____________________________________________________________________________________________
                    |          |   Bu    |    Bu    |   Bu    |   Bu    |    Tons    |    AUM*
                    |          |         |          |         |         |            |
      960D2---------|          |    94   |     30   |    57   |    40   |     3.9    |    6.5
       Hickory------|     3e   |         |          |         |         |            |
       Sylvan-------|     3e   |         |          |         |         |            |
       Fayette------|     3e   |         |          |         |         |            |
                    |          |         |          |         |         |            |
      960D3---------|          |    88   |     28   |    54   |    37   |     3.6    |    6.0
       Hickory------|     4e   |         |          |         |         |            |
       Sylvan-------|     4e   |         |          |         |         |            |
       Fayette------|     4e   |         |          |         |         |            |
                    |          |         |          |         |         |            |
      960F----------|          |   ---   |    ---   |   ---   |   ---   |     3.4    |    5.7
       Hickory------|     6e   |         |          |         |         |            |
       Sylvan-------|     6e   |         |          |         |         |            |
       Fayette------|     6e   |         |          |         |         |            |
                    |          |         |          |         |         |            |
      961A----------|          |    72   |     25   |    50   |    34   |     2.8    |    4.7
       Burkhardt----|     2s   |         |          |         |         |            |
       Saude--------|     2s   |         |          |         |         |            |
                    |          |         |          |         |         |            |
      962F----------|          |   ---   |    ---   |   ---   |   ---   |     3.6    |    6.0
       Sylvan-------|     6e   |         |          |         |         |            |
       Bold---------|     6e   |         |          |         |         |            |
                    |          |         |          |         |         |            |
      1076A:        |          |         |          |         |         |            |
       Otter--------|     5w   |   ---   |    ---   |   ---   |   ---   |     ---    |    ---
                    |          |         |          |         |         |            |
      1082A:        |          |         |          |         |         |            |
       Millington---|     5w   |   ---   |    ---   |   ---   |   ---   |     ---    |    ---
                    |          |         |          |         |         |            |
      1107A:        |          |         |          |         |         |            |
       Sawmill------|     5w   |   ---   |    ---   |   ---   |   ---   |     ---    |    ---
                    |          |         |          |         |         |            |
      1334A:        |          |         |          |         |         |            |
       Birds--------|     5w   |   ---   |    ---   |   ---   |   ---   |     ---    |    ---
                    |          |         |          |         |         |            |
      1400A:        |          |         |          |         |         |            |
       Calco--------|     5w   |   ---   |    ---   |   ---   |   ---   |     ---    |    ---
                    |          |         |          |         |         |            |
      1654A:        |          |         |          |         |         |            |
       Moline-------|     5w   |   ---   |    ---   |   ---   |   ---   |     ---    |    ---
                    |          |         |          |         |         |            |
      3074A:        |          |         |          |         |         |            |
       Radford------|     3w   |   129   |     41   |   ---   |   ---   |     5.0    |    8.4
                    |          |         |          |         |         |            |
      3076A:        |          |         |          |         |         |            |
       Otter--------|     3w   |   129   |     41   |    62   |    44   |     4.2    |    7.1
                    |          |         |          |         |         |            |
      3082A:        |          |         |          |         |         |            |
       Millington---|     3w   |   120   |     37   |   ---   |   ---   |     4.1    |    6.9
                    |          |         |          |         |         |            |
      3083A:        |          |         |          |         |         |            |
       Wabash-------|     3w   |    95   |     32   |   ---   |   ---   |     3.3    |    5.6
                    |          |         |          |         |         |            |
      3107A:        |          |         |          |         |         |            |
       Sawmill------|     3w   |   132   |     42   |   ---   |   ---   |     5.0    |    8.3
                    |          |         |          |         |         |            |
      3239A:        |          |         |          |         |         |            |
       Dorchester---|     2w   |   119   |     39   |   ---   |   ---   |     4.8    |    8.0
                    |          |         |          |         |         |            |

          See footnote at end of table.
Rock Island County, Illinois                                                                                 169



                      Table 6.--Land Capability and Yields per Acre of Crops and Pasture--Continued
              ____________________________________________________________________________________________
                            |          |         |          |         |         |            |
                Map symbol | Land      | Corn    | Soybeans | Oats    | Winter |Grass-legume|Grass-legume
              and soil name |capability|         |          |         | wheat   |    hay     | pasture
                            |          |         |          |         |         |            |
              ____________________________________________________________________________________________
                            |          |   Bu    |    Bu    |   Bu    |   Bu    |    Tons    |    AUM*
                            |          |         |          |         |         |            |
              3400A:        |          |         |          |         |         |            |
               Calco--------|     2w   |   119   |     40   |   ---   |   ---   |     4.2    |    7.0
                            |          |         |          |         |         |            |
              3415A:        |          |         |          |         |         |            |
               Orion--------|     3w   |    80   |     26   |   ---   |   ---   |     4.2    |    7.0
                            |          |         |          |         |         |            |
              3428A:        |          |         |          |         |         |            |
               Coffeen------|     2w   |   137   |     42   |   ---   |   ---   |     5.2    |    8.7
                            |          |         |          |         |         |            |
              3451A:        |          |         |          |         |         |            |
               Lawson-------|     3w   |   145   |     43   |    77   |    56   |     5.1    |    8.6
                            |          |         |          |         |         |            |
              3646L:        |          |         |          |         |         |            |
               Fluvaquents--|     5w   |   ---   |    ---   |   ---   |   ---   |     ---    |    ---
                            |          |         |          |         |         |            |
              7076A:        |          |         |          |         |         |            |
               Otter--------|     2w   |   143   |     46   |    69   |    49   |     4.7    |    7.8
                            |          |         |          |         |         |            |
              7083A:        |          |         |          |         |         |            |
               Wabash-------|     3w   |   106   |     35   |    55   |    43   |     3.7    |    6.2
                            |          |         |          |         |         |            |
              7107A:        |          |         |          |         |         |            |
               Sawmill------|     2w   |   147   |     47   |    76   |    54   |     5.5    |    9.2
                            |          |         |          |         |         |            |
              7239A:        |          |         |          |         |         |            |
               Dorchester---|     1    |   132   |     43   |    76   |    54   |     5.3    |    8.8
                            |          |         |          |         |         |            |
              7304A:        |          |         |          |         |         |            |
               Landes-------|     2s   |    99   |     34   |    62   |    45   |     3.7    |    6.2
                            |          |         |          |         |         |            |
              7415A:        |          |         |          |         |         |            |
               Orion--------|     2w   |   135   |     43   |    72   |    52   |     4.7    |    7.8
                            |          |         |          |         |         |            |
              7428A:        |          |         |          |         |         |            |
               Coffeen------|     1    |   152   |     47   |    79   |    57   |     5.8    |    9.7
                            |          |         |          |         |         |            |
              7451A:        |          |         |          |         |         |            |
               Lawson-------|     2w   |   161   |     48   |    86   |    62   |     5.7    |    9.5
                            |          |         |          |         |         |            |
              7654A:        |          |         |          |         |         |            |
               Moline-------|     3w   |   115   |     39   |    64   |    47   |     4.2    |    7.0
                            |          |         |          |         |         |            |
              8107+:        |          |         |          |         |         |            |
               Sawmill------|     2w   |   147   |     47   |    76   |    54   |     5.5    |    9.2
                            |          |         |          |         |         |            |
              8302A:        |          |         |          |         |         |            |
               Ambraw-------|     2w   |   132   |     43   |    70   |    52   |     4.6    |    7.7
                            |          |         |          |         |         |            |
              8400A:        |          |         |          |         |         |            |
               Calco--------|     2w   |   132   |     44   |    72   |    52   |     4.7    |    7.8
                            |          |         |          |         |         |            |
              8404A:        |          |         |          |         |         |            |
               Titus--------|     3w   |   125   |     42   |    68   |    52   |     4.3    |    7.2
                            |          |         |          |         |         |            |
              ____________________________________________________________________________________________

                  * Animal unit month: The amount of forage or feed required to feed one animal unit (one
              cow, one horse, one mule, five sheep, or five goats) for 30 days.
170                                                                                                    Soil Survey of



                                             Table 7.--Prime Farmland

      (Only the soils considered prime farmland are listed. Urban or built-up areas of the soils listed are
           not considered prime farmland. If a soil is prime farmland only under certain conditions, the
           conditions are specified in parentheses after the soil name)

      _______________________________________________________________________________________________________
             |
        Map |                                             Soil name
      symbol |
             |
      _______________________________________________________________________________________________________
             |
      45A    |Denny silt loam, 0 to 2 percent slopes (where drained)
      51A    |Muscatune silt loam, 0 to 2 percent slopes
      61A    |Atterberry silt loam, 0 to 2 percent slopes (where drained)
      68A    |Sable silty clay loam, 0 to 2 percent slopes (where drained)
      86B    |Osco silt loam, 2 to 5 percent slopes
      87A    |Dickinson sandy loam, 0 to 2 percent slopes
      87C2   |Dickinson sandy loam, 5 to 10 percent slopes, eroded
      172A   |Hoopeston sandy loam, 0 to 2 percent slopes
      212B   |Thebes silt loam, 2 to 5 percent slopes
      261A   |Niota silt loam, 0 to 2 percent slopes (where drained)
      274B   |Seaton silt loam, 2 to 5 percent slopes
      274B2 |Seaton silt loam, 2 to 5 percent slopes, eroded
      275A   |Joy silt loam, 0 to 2 percent slopes
      278A   |Stronghurst silt loam, 0 to 2 percent slopes (where drained)
      279A   |Rozetta silt loam, 0 to 2 percent slopes
      279B   |Rozetta silt loam, 2 to 5 percent slopes
      280B   |Fayette silt loam, 2 to 5 percent slopes
      280B2 |Fayette silt loam, 2 to 5 percent slopes, eroded
      317A   |Millsdale silty clay loam, 0 to 2 percent slopes (where drained)
      430A   |Raddle silt loam, 0 to 2 percent slopes
      430B   |Raddle silt loam, 2 to 5 percent slopes
      525A   |Joslin loam, bedrock substratum, 0 to 2 percent slopes
      570B   |Martinsville silt loam, 2 to 5 percent slopes
      647A   |Lawler loam, 0 to 2 percent slopes
      671A   |Biggsville silt loam, 0 to 2 percent slopes
      671B   |Biggsville silt loam, 2 to 5 percent slopes
      675A   |Greenbush silt loam, 0 to 2 percent slopes
      675B   |Greenbush silt loam, 2 to 5 percent slopes
      705A   |Buckhart silt loam, 0 to 2 percent slopes
      727A   |Waukee loam, 0 to 2 percent slopes
      763A   |Joslin silt loam, 0 to 2 percent slopes
      763B   |Joslin silt loam, 2 to 5 percent slopes
      764A   |Coyne fine sandy loam, 0 to 2 percent slopes
      774A   |Saude loam, 0 to 2 percent slopes
      961A   |Burkhardt-Saude complex, 0 to 2 percent slopes
      3074A |Radford silt loam, 0 to 2 percent slopes, frequently flooded (where protected from flooding
             | or not frequently flooded during the growing season)
      3076A |Otter silt loam, 0 to 2 percent slopes, frequently flooded (where drained and either
             | protected from flooding or not frequently flooded during the growing season)
      3082A |Millington silt loam, 0 to 2 percent slopes, frequently flooded (where drained and either
             | protected from flooding or not frequently flooded during the growing season)
      3083A |Wabash silty clay, 0 to 2 percent slopes, frequently flooded (where drained and either
             | protected from flooding or not frequently flooded during the growing season)
      3107A |Sawmill silty clay loam, 0 to 2 percent slopes, frequently flooded (where drained and
             | either protected from flooding or not frequently flooded during the growing season)
      3239A |Dorchester silt loam, 0 to 2 percent slopes, frequently flooded (where drained and either
             | protected from flooding or not frequently flooded during the growing season)
      3400A |Calco silty clay loam, 0 to 2 percent slopes, frequently flooded (where drained and either
             | protected from flooding or not frequently flooded during the growing season)
      3415A |Orion silt loam, 0 to 2 percent slopes, frequently flooded (where protected from flooding or
             | not frequently flooded during the growing season)
      3428A |Coffeen silt loam, 0 to 2 percent slopes, frequently flooded (where protected from flooding
             | or not frequently flooded during the growing season)
      3451A |Lawson silt loam, 0 to 2 percent slopes, frequently flooded (where protected from flooding
             | or not frequently flooded during the growing season)
      7076A |Otter silt loam, 0 to 2 percent slopes, rarely flooded (where drained)
      7083A |Wabash silty clay, 0 to 2 percent slopes, rarely flooded (where drained)
      7107A |Sawmill silty clay loam, 0 to 2 percent slopes, rarely flooded (where drained)
             |
Rock Island County, Illinois                                                                                      171



                                          Table 7.--Prime Farmland--Continued
        _______________________________________________________________________________________________________
               |
          Map |                                            Soil name
        symbol |
               |
        _______________________________________________________________________________________________________
               |
        7239A |Dorchester silt loam, 0 to 2 percent slopes, rarely flooded
        7304A |Landes fine sandy loam, 0 to 2 percent slopes, rarely flooded
        7415A |Orion silt loam, 0 to 2 percent slopes, rarely flooded
        7428A |Coffeen silt loam, 0 to 2 percent slopes, rarely flooded
        7451A |Lawson silt loam, 0 to 2 percent slopes, rarely flooded
        7654A |Moline silty clay, 0 to 2 percent slopes, rarely flooded (where drained)
        8107+ |Sawmill silt loam, 0 to 2 percent slopes, occasionally flooded, overwash (where drained)
        8302A |Ambraw loam, 0 to 2 percent slopes, occasionally flooded (where drained)
        8400A |Calco silty clay loam, 0 to 2 percent slopes, occasionally flooded (where drained)
        8404A |Titus silty clay loam, 0 to 2 percent slopes, occasionally flooded (where drained)
               |
        _______________________________________________________________________________________________________
172                                                                                       Soil Survey of



                              Table 8.--Forestland Productivity

           (Only the soils suitable for production of commercial trees are listed)

      _________________________________________________________________________________
                                      Potential productivity
                               |___________________________________|
            Map symbol and     |                    |     |        |
               soil name       |    Common trees    |Site | Volume | Trees to manage
                               |                    |index|of wood |
                               |                    |     | fiber |
      _________________________________________________________________________________
                               |                    |     |cu ft/ac|
                               |                    |     |        |
      8D2, 8D3, 8F, 8F3:       |                    |     |        |
       Hickory-----------------|Bitternut hickory---| --- |   --- |Black walnut,
                               |Black oak-----------| --- |   --- | eastern
                               |Green ash-----------| --- |   --- | cottonwood,
                               |Northern red oak----| 85 |     72 | eastern white
                               |Tuliptree-----------| 95 |    100 | pine, green ash,
                               |White oak-----------| 85 |     72 | northern red oak,
                               |                    |     |        | pecan, pin oak,
                               |                    |     |        | tuliptree, white
                               |                    |     |        | oak
                               |                    |     |        |
      19C3, 19D, 19D3, 19F,    |                    |     |        |
       19F3:                   |                    |     |        |
        Sylvan-----------------|Black walnut--------| --- |   --- |Black walnut,
                               |Northern red oak----| 80 |     57 | eastern
                               |Tuliptree-----------| 90 |     86 | cottonwood,
                               |White oak-----------| 80 |     57 | eastern white
                               |                    |     |        | pine, green ash,
                               |                    |     |        | northern red oak,
                               |                    |     |        | pecan, pin oak,
                               |                    |     |        | tuliptree, white
                               |                    |     |        | oak
                               |                    |     |        |
      88A:                     |                    |     |        |
       Sparta------------------|Eastern white pine--| --- |   --- |Common hackberry,
                               |Jack pine-----------| --- |   --- | eastern redcedar,
                               |Northern red oak----| 70 |     57 | eastern white
                               |Red pine------------| --- |   --- | pine, green ash,
                               |                    |     |        | red maple, red
                               |                    |     |        | pine, shortleaf
                               |                    |     |        | pine
                               |                    |     |        |
      274B, 274B2, 274C2,      |                    |     |        |
       274D2:                  |                    |     |        |
        Seaton-----------------|Black walnut--------| --- |   --- |Black walnut,
                               |Northern red oak----| 80 |     57 | eastern
                               |Tuliptree-----------| 90 |     86 | cottonwood,
                               |White oak-----------| 90 |     72 | eastern white
                               |                    |     |        | pine, green ash,
                               |                    |     |        | northern red oak,
                               |                    |     |        | pecan, pin oak,
                               |                    |     |        | tuliptree, white
                               |                    |     |        | oak
                               |                    |     |        |
      278A:                    |                    |     |        |
       Stronghurst-------------|Bur oak-------------| --- |   --- |Common hackberry,
                               |Green ash-----------| --- |   --- | common persimmon,
                               |Northern red oak----| 70 |     57 | eastern
                               |White oak-----------| 70 |     57 | cottonwood, green
                               |                    |     |        | ash, pecan, pin
                               |                    |     |        | oak, swamp white
                               |                    |     |        | oak
                               |                    |     |        |
Rock Island County, Illinois                                                                           173



                                       Table 8.--Forestland Productivity--Continued
                   _________________________________________________________________________________
                                                    Potential productivity
                                             |___________________________________|
                         Map symbol and      |                    |     |        |
                            soil name        |    Common trees    |Site | Volume | Trees to manage
                                             |                    |index|of wood |
                                             |                    |     | fiber |
                   _________________________________________________________________________________
                                             |                    |     |cu ft/ac|
                                             |                    |     |        |
                   279A, 279B:               |                    |     |        |
                    Rozetta-----------------|Black walnut--------| --- |    --- |Black walnut,
                                             |Northern red oak----| 80 |     57 | eastern
                                             |Tuliptree-----------| 90 |     86 | cottonwood,
                                             |White oak-----------| 80 |     57 | eastern white
                                             |                    |     |        | pine, green ash,
                                             |                    |     |        | northern red oak,
                                             |                    |     |        | pecan, pin oak,
                                             |                    |     |        | tuliptree, white
                                             |                    |     |        | oak
                                             |                    |     |        |
                   280B, 280B2, 280C2,       |                    |     |        |
                    280C3:                   |                    |     |        |
                     Fayette----------------|Black walnut--------| --- |    --- |Black walnut,
                                             |Northern red oak----| 80 |     57 | eastern
                                             |Tuliptree-----------| 90 |     86 | cottonwood,
                                             |White oak-----------| 80 |     57 | eastern white
                                             |                    |     |        | pine, green ash,
                                             |                    |     |        | northern red oak,
                                             |                    |     |        | pecan, pin oak,
                                             |                    |     |        | tuliptree, white
                                             |                    |     |        | oak
                                             |                    |     |        |
                   570B, 570C3, 570D3:       |                    |     |        |
                    Martinsville------------|Sweetgum------------| 76 |      72 |Black walnut,
                                             |Tuliptree-----------| 98 |    100 | eastern
                                             |White oak-----------| 80 |     57 | cottonwood,
                                             |                    |     |        | eastern white
                                             |                    |     |        | pine, green ash,
                                             |                    |     |        | northern red oak,
                                             |                    |     |        | pecan, pin oak,
                                             |                    |     |        | tuliptree, white
                                             |                    |     |        | oak
                                             |                    |     |        |
                   689B, 689D:               |                    |     |        |
                    Coloma------------------|Eastern white pine--| 85 |     200 |Common hackberry,
                                             |Jack pine-----------| 68 |    100 | eastern redcedar,
                                             |Red pine------------| 78 |    143 | eastern white
                                             |White oak-----------| 70 |     72 | pine, green ash,
                                             |                    |     |        | red maple, red
                                             |                    |     |        | pine, shortleaf
                                             |                    |     |        | pine
                                             |                    |     |        |
                   741F:                     |                    |     |        |
                    Oakville----------------|Eastern white pine--| 85 |     200 |Common hackberry,
                                             |Jack pine-----------| 68 |    100 | eastern redcedar,
                                             |Red pine------------| 78 |    143 | eastern white
                                             |White oak-----------| 70 |     72 | pine, green ash,
                                             |                    |     |        | red maple, red
                                             |                    |     |        | pine, shortleaf
                                             |                    |     |        | pine
                                             |                    |     |        |
                   898F3:                    |                    |     |        |
                    Hickory-----------------|Bitternut hickory---| --- |    --- |Black walnut,
                                             |Black oak-----------| --- |   --- | eastern
                                             |Green ash-----------| --- |   --- | cottonwood,
                                             |Northern red oak----| 85 |     72 | eastern white
                                             |Tuliptree-----------| 95 |    100 | pine, green ash,
                                             |White oak-----------| 85 |     72 | northern red oak,
                                             |                    |     |        | pecan, pin oak,
                                             |                    |     |        | tuliptree, white
                                             |                    |     |        | oak
                                             |                    |     |        |
174                                                                                       Soil Survey of



                         Table 8.--Forestland Productivity--Continued
      _________________________________________________________________________________
                                      Potential productivity
                               |___________________________________|
           Map symbol and      |                    |     |        |
              soil name        |    Common trees    |Site | Volume | Trees to manage
                               |                    |index|of wood |
                               |                    |     | fiber |
      _________________________________________________________________________________
                               |                    |     |cu ft/ac|
                               |                    |     |        |
      898F3:                   |                    |     |        |
       Sylvan------------------|Black walnut--------| --- |   --- |Black walnut,
                               |Northern red oak----| 80 |     57 | eastern
                               |Tuliptree-----------| 90 |     86 | cottonwood,
                               |White oak-----------| 80 |     57 | eastern white
                               |                    |     |        | pine, green ash,
                               |                    |     |        | northern red oak,
                               |                    |     |        | pecan, pin oak,
                               |                    |     |        | tuliptree, white
                               |                    |     |        | oak
                               |                    |     |        |
      913D2, 913F, 913G:       |                    |     |        |
       Marseilles--------------|Black oak-----------| --- |   --- |Black oak, common
                               |Northern red oak----| 66 |     43 | hackberry, eastern
                               |White ash-----------| --- |   --- | white pine, green
                               |White oak-----------| 66 |     43 | ash
                               |                    |     |        |
       Hickory-----------------|Bitternut hickory---| --- |   --- |Black walnut,
                               |Black oak-----------| --- |   --- | eastern
                               |Green ash-----------| --- |   --- | cottonwood,
                               |Northern red oak----| 85 |     72 | eastern white
                               |Tuliptree-----------| 95 |    100 | pine, green ash,
                               |White oak-----------| 85 |     72 | northern red oak,
                               |                    |     |        | pecan, pin oak,
                               |                    |     |        | tuliptree, white
                               |                    |     |        | oak
                               |                    |     |        |
      917C2, 917D2:            |                    |     |        |
       Oakville----------------|Eastern white pine--| 85 |    200 |Common hackberry,
                               |Jack pine-----------| 68 |    100 | eastern redcedar,
                               |Red pine------------| 78 |    143 | eastern white
                               |White oak-----------| 70 |     72 | pine, green ash,
                               |                    |     |        | red maple, red
                               |                    |     |        | pine, shortleaf
                               |                    |     |        | pine
                               |                    |     |        |
       Tell--------------------|Northern red oak----| 75 |     57 |Black oak, common
                               |White oak-----------| 75 |     57 | hackberry, eastern
                               |                    |     |        | white pine, green
                               |                    |     |        | ash, red pine
                               |                    |     |        |
      943D2, 943F2:            |                    |     |        |
       Seaton------------------|Black walnut--------| --- |   --- |Black walnut,
                               |Northern red oak----| 80 |     57 | eastern
                               |Tuliptree-----------| 90 |     86 | cottonwood,
                               |White oak-----------| 90 |     72 | eastern white
                               |                    |     |        | pine, green ash,
                               |                    |     |        | northern red oak,
                               |                    |     |        | pecan, pin oak,
                               |                    |     |        | tuliptree, white
                               |                    |     |        | oak
                               |                    |     |        |
       Timula------------------|Bur oak-------------| --- |   --- |Black walnut,
                               |Green ash-----------| --- |   --- | eastern
                               |Northern red oak----| --- |   --- | cottonwood,
                               |White oak-----------| 70 |     57 | eastern white
                               |                    |     |        | pine, green ash,
                               |                    |     |        | northern red oak,
                               |                    |     |        | pecan, pin oak,
                               |                    |     |        | tuliptree, white
                               |                    |     |        | oak
                               |                    |     |        |
Rock Island County, Illinois                                                                           175



                                       Table 8.--Forestland Productivity--Continued
                   _________________________________________________________________________________
                                                    Potential productivity
                                             |___________________________________|
                         Map symbol and      |                    |     |        |
                            soil name        |    Common trees    |Site | Volume | Trees to manage
                                             |                    |index|of wood |
                                             |                    |     | fiber |
                   _________________________________________________________________________________
                                             |                    |     |cu ft/ac|
                                             |                    |     |        |
                   946D3, 946F3:             |                    |     |        |
                    Hickory-----------------|Bitternut hickory---| --- |    --- |Black walnut,
                                             |Black oak-----------| --- |   --- | eastern
                                             |Green ash-----------| --- |   --- | cottonwood,
                                             |Northern red oak----| 85 |     72 | eastern white
                                             |Tuliptree-----------| 95 |    100 | pine, green ash,
                                             |White oak-----------| 85 |     72 | northern red oak,
                                             |                    |     |        | pecan, pin oak,
                                             |                    |     |        | tuliptree, white
                                             |                    |     |        | oak
                                             |                    |     |        |
                    Atlas-------------------|Bur oak-------------| 70 |      57 |Black oak, bur oak,
                                             |Green ash-----------| --- |   --- | chinkapin oak,
                                             |Northern red oak----| 70 |     57 | common hackberry,
                                             |White oak-----------| 70 |     57 | eastern redcedar,
                                             |                    |     |        | green ash
                                             |                    |     |        |
                   959G:                     |                    |     |        |
                    Strawn------------------|Black walnut--------| --- |      0 |Black walnut,
                                             |Northern red oak----| 80 |     57 | eastern
                                             |Tuliptree-----------| 90 |     86 | cottonwood,
                                             |White oak-----------| 80 |     57 | eastern white
                                             |                    |     |        | pine, green ash,
                                             |                    |     |        | northern red oak,
                                             |                    |     |        | pecan, pin oak,
                                             |                    |     |        | tuliptree, white
                                             |                    |     |        | oak
                                             |                    |     |        |
                    Chute-------------------|          ---        | --- |   --- |Common hackberry,
                                             |                    |     |        | eastern redcedar,
                                             |                    |     |        | eastern white
                                             |                    |     |        | pine, green ash,
                                             |                    |     |        | red maple
                                             |                    |     |        |
                   960D2, 960D3, 960F:       |                    |     |        |
                    Hickory-----------------|Bitternut hickory---| --- |    --- |Black walnut,
                                             |Black oak-----------| --- |   --- | eastern
                                             |Green ash-----------| --- |   --- | cottonwood,
                                             |Northern red oak----| 85 |     72 | eastern white
                                             |Tuliptree-----------| 95 |    100 | pine, green ash,
                                             |White oak-----------| 85 |     72 | northern red oak,
                                             |                    |     |        | pecan, pin oak,
                                             |                    |     |        | tuliptree, white
                                             |                    |     |        | oak
                                             |                    |     |        |
                    Sylvan------------------|Black walnut--------| --- |    --- |Black walnut,
                                             |Northern red oak----| 80 |     57 | eastern
                                             |Tuliptree-----------| 90 |     86 | cottonwood,
                                             |White oak-----------| 80 |     57 | eastern white
                                             |                    |     |        | pine, green ash,
                                             |                    |     |        | northern red oak,
                                             |                    |     |        | pecan, pin oak,
                                             |                    |     |        | tuliptree, white
                                             |                    |     |        | oak
                                             |                    |     |        |
176                                                                                        Soil Survey of



                          Table 8.--Forestland Productivity--Continued
      _________________________________________________________________________________
                                       Potential productivity
                                |___________________________________|
            Map symbol and      |                    |     |        |
               soil name        |    Common trees    |Site | Volume | Trees to manage
                                |                    |index|of wood |
                                |                    |     | fiber |
      _________________________________________________________________________________
                                |                    |     |cu ft/ac|
                                |                    |     |        |
      960D2, 960D3, 960F:       |                    |     |        |
       Fayette-----------------|Black walnut--------| --- |    --- |Black walnut,
                                |Northern red oak----| 80 |     57 | eastern
                                |Tuliptree-----------| 90 |     86 | cottonwood,
                                |White oak-----------| 80 |     57 | eastern white
                                |                    |     |        | pine, green ash,
                                |                    |     |        | northern red oak,
                                |                    |     |        | pecan, pin oak,
                                |                    |     |        | tuliptree, white
                                |                    |     |        | oak
                                |                    |     |        |
      962F:                     |                    |     |        |
       Sylvan------------------|Black walnut--------| --- |    --- |Black walnut,
                                |Northern red oak----| 80 |     57 | eastern
                                |Tuliptree-----------| 90 |     86 | cottonwood,
                                |White oak-----------| 80 |     57 | eastern white
                                |                    |     |        | pine, green ash,
                                |                    |     |        | northern red oak,
                                |                    |     |        | pecan, pin oak,
                                |                    |     |        | tuliptree, white
                                |                    |     |        | oak
                                |                    |     |        |
       Bold--------------------|          ---        | --- |   --- |Bur oak, chinkapin
                                |                    |     |        | oak, common
                                |                    |     |        | hackberry, eastern
                                |                    |     |        | cottonwood,
                                |                    |     |        | eastern redcedar,
                                |                    |     |        | green ash
                                |                    |     |        |
      _________________________________________________________________________________
Rock Island County, Illinois                                                                                     177



                                           Table 9a.--Forestland Management

          (Only the soils suitable for production of commercial trees are listed. The information in this
               table indicates the dominant soil condition but does not eliminate the need for onsite
               investigation. The numbers in the value columns range from 0.01 to 1.00. The larger the value,
               the greater the limitation. See text for further explanation of ratings in this table)

          ___________________________________________________________________________________________________
                               |                          |                         |
                Map symbol     | Limitations affecting |        Suitability for     |       Soil rutting
               and soil name   |     construction of      |      log landings       |          hazard
                               |     haul roads and       |                         |
                                       log landings       |                         |
                               |_____________________________________________________________________________
                               | Rating class and |Value| Rating class and |Value| Rating class and |Value
                               | limiting features |      | limiting features |     | limiting features |
          ___________________________________________________________________________________________________
                               |                    |     |                   |     |                    |
          8D2, 8D3:            |                    |     |                   |     |                    |
           Hickory-------------|Moderate            |     |Poorly suited      |     |Severe              |
                               | Low strength       |0.50 | Slope             |1.00 | Low strength       |1.00
                               |                    |     | Low strength      |0.50 |                    |
                               |                    |     |                   |     |                    |
          8F, 8F3:             |                    |     |                   |     |                    |
           Hickory-------------|Moderate            |     |Poorly suited      |     |Severe              |
                               | Slope              |0.50 | Slope             |1.00 | Low strength       |1.00
                               | Low strength       |0.50 | Low strength      |0.50 |                    |
                               |                    |     |                   |     |                    |
          19C3:                |                    |     |                   |     |                    |
           Sylvan--------------|Moderate            |     |Moderately suited |      |Severe              |
                               | Low strength       |0.50 | Low strength      |0.50 | Low strength       |1.00
                               |                    |     | Slope             |0.50 |                    |
                               |                    |     |                   |     |                    |
          19D:                 |                    |     |                   |     |                    |
           Sylvan--------------|Slight              |     |Poorly suited      |     |Severe              |
                               |                    |     | Slope             |1.00 | Low strength       |1.00
                               |                    |     | Low strength      |0.50 |                    |
                               |                    |     |                   |     |                    |
          19D3:                |                    |     |                   |     |                    |
           Sylvan--------------|Moderate            |     |Poorly suited      |     |Severe              |
                               | Low strength       |0.50 | Slope             |1.00 | Low strength       |1.00
                               |                    |     | Low strength      |0.50 |                    |
                               |                    |     |                   |     |                    |
          19F, 19F3:           |                    |     |                   |     |                    |
           Sylvan--------------|Moderate            |     |Poorly suited      |     |Severe              |
                               | Slope              |0.50 | Slope             |1.00 | Low strength       |1.00
                               | Low strength       |0.50 | Low strength      |0.50 |                    |
                               |                    |     |                   |     |                    |
          88A:                 |                    |     |                   |     |                    |
           Sparta--------------|Moderate            |     |Moderately suited |      |Moderate            |
                               | Sandiness          |0.50 | Sandiness         |0.50 | Low strength       |0.50
                               |                    |     |                   |     |                    |
          274B, 274B2:         |                    |     |                   |     |                    |
           Seaton--------------|Moderate            |     |Moderately suited |      |Severe              |
                               | Low strength       |0.50 | Low strength      |0.50 | Low strength       |1.00
                               |                    |     |                   |     |                    |
          274C2:               |                    |     |                   |     |                    |
           Seaton--------------|Moderate            |     |Moderately suited |      |Severe              |
                               | Low strength       |0.50 | Low strength      |0.50 | Low strength       |1.00
                               |                    |     | Slope             |0.50 |                    |
                               |                    |     |                   |     |                    |
          274D2:               |                    |     |                   |     |                    |
           Seaton--------------|Moderate            |     |Poorly suited      |     |Severe              |
                               | Low strength       |0.50 | Slope             |1.00 | Low strength       |1.00
                               |                    |     | Low strength      |0.50 |                    |
                               |                    |     |                   |     |                    |
          278A:                |                    |     |                   |     |                    |
           Stronghurst---------|Moderate            |     |Moderately suited |      |Severe              |
                               | Low strength       |0.50 | Low strength      |0.50 | Low strength       |1.00
                               |                    |     | Wetness           |0.50 |                    |
                               |                    |     |                   |     |                    |
178                                                                                                  Soil Survey of



                                   Table 9a.--Forestland Management--Continued
      ___________________________________________________________________________________________________
                           |                          |                         |
            Map symbol     | Limitations affecting |        Suitability for     |       Soil rutting
          and soil name    |     construction of      |      log landings       |          hazard
                           |     haul roads and       |                         |
                                   log landings       |                         |
                           |_____________________________________________________________________________
                           | Rating class and |Value| Rating class and |Value| Rating class and |Value
                           | limiting features |      | limiting features |     | limiting features |
      ___________________________________________________________________________________________________
                           |                    |     |                   |     |                    |
      279A, 279B:          |                    |     |                   |     |                    |
       Rozetta-------------|Moderate            |     |Moderately suited |      |Severe              |
                           | Low strength       |0.50 | Low strength      |0.50 | Low strength       |1.00
                           |                    |     |                   |     |                    |
      280B, 280B2:         |                    |     |                   |     |                    |
       Fayette-------------|Moderate            |     |Moderately suited |      |Severe              |
                           | Low strength       |0.50 | Low strength      |0.50 | Low strength       |1.00
                           |                    |     |                   |     |                    |
      280C2, 280C3:        |                    |     |                   |     |                    |
       Fayette-------------|Moderate            |     |Moderately suited |      |Severe              |
                           | Low strength       |0.50 | Low strength      |0.50 | Low strength       |1.00
                           |                    |     | Slope             |0.50 |                    |
                           |                    |     |                   |     |                    |
      570B:                |                    |     |                   |     |                    |
       Martinsville--------|Moderate            |     |Moderately suited |      |Severe              |
                           | Low strength       |0.50 | Low strength      |0.50 | Low strength       |1.00
                           |                    |     |                   |     |                    |
      570C3:               |                    |     |                   |     |                    |
       Martinsville--------|Moderate            |     |Moderately suited |      |Severe              |
                           | Low strength       |0.50 | Low strength      |0.50 | Low strength       |1.00
                           |                    |     | Slope             |0.50 |                    |
                           |                    |     |                   |     |                    |
      570D3:               |                    |     |                   |     |                    |
       Martinsville--------|Moderate            |     |Poorly suited      |     |Severe              |
                           | Low strength       |0.50 | Slope             |1.00 | Low strength       |1.00
                           |                    |     | Low strength      |0.50 |                    |
                           |                    |     |                   |     |                    |
      689B:                |                    |     |                   |     |                    |
       Coloma--------------|Moderate            |     |Moderately suited |      |Moderate            |
                           | Sandiness          |0.50 | Sandiness         |0.50 | Low strength       |0.50
                           |                    |     |                   |     |                    |
      689D:                |                    |     |                   |     |                    |
       Coloma--------------|Moderate            |     |Moderately suited |      |Moderate            |
                           | Sandiness          |0.50 | Slope             |0.50 | Low strength       |0.50
                           |                    |     | Sandiness         |0.50 |                    |
                           |                    |     |                   |     |                    |
      741F:                |                    |     |                   |     |                    |
       Oakville------------|Moderate            |     |Poorly suited      |     |Moderate            |
                           | Slope              |0.50 | Slope             |1.00 | Low strength       |0.50
                           | Sandiness          |0.50 | Sandiness         |0.50 |                    |
                           |                    |     |                   |     |                    |
      898F3:               |                    |     |                   |     |                    |
       Hickory-------------|Moderate            |     |Poorly suited      |     |Severe              |
                           | Slope              |0.50 | Slope             |1.00 | Low strength       |1.00
                           | Low strength       |0.50 | Low strength      |0.50 |                    |
                           |                    |     |                   |     |                    |
       Sylvan--------------|Moderate            |     |Poorly suited      |     |Severe              |
                           | Slope              |0.50 | Slope             |1.00 | Low strength       |1.00
                           | Low strength       |0.50 | Low strength      |0.50 |                    |
                           |                    |     |                   |     |                    |
      898G:                |                    |     |                   |     |                    |
       Hickory-------------|Severe              |     |Poorly suited      |     |Severe              |
                           | Slope              |1.00 | Slope             |1.00 | Low strength       |1.00
                           | Low strength       |0.50 | Low strength      |0.50 |                    |
                           |                    |     |                   |     |                    |
       Sylvan--------------|Severe              |     |Poorly suited      |     |Severe              |
                           | Slope              |1.00 | Slope             |1.00 | Low strength       |1.00
                           | Low strength       |0.50 | Low strength      |0.50 |                    |
                           |                    |     |                   |     |                    |
Rock Island County, Illinois                                                                                     179



                                       Table 9a.--Forestland Management--Continued
          ___________________________________________________________________________________________________
                               |                          |                         |
                Map symbol     | Limitations affecting |        Suitability for     |       Soil rutting
              and soil name    |     construction of      |      log landings       |          hazard
                               |     haul roads and       |                         |
                                       log landings       |                         |
                               |_____________________________________________________________________________
                               | Rating class and |Value| Rating class and |Value| Rating class and |Value
                               | limiting features |      | limiting features |     | limiting features |
          ___________________________________________________________________________________________________
                               |                    |     |                   |     |                    |
          913D2:               |                    |     |                   |     |                    |
           Marseilles----------|Moderate            |     |Poorly suited      |     |Severe              |
                               | Low strength       |0.50 | Slope             |1.00 | Low strength       |1.00
                               |                    |     | Low strength      |0.50 |                    |
                               |                    |     |                   |     |                    |
           Hickory-------------|Moderate            |     |Poorly suited      |     |Severe              |
                               | Low strength       |0.50 | Slope             |1.00 | Low strength       |1.00
                               |                    |     | Low strength      |0.50 |                    |
                               |                    |     |                   |     |                    |
          913F:                |                    |     |                   |     |                    |
           Marseilles----------|Moderate            |     |Poorly suited      |     |Severe              |
                               | Slope              |0.50 | Slope             |1.00 | Low strength       |1.00
                               | Low strength       |0.50 | Low strength      |0.50 |                    |
                               |                    |     |                   |     |                    |
           Hickory-------------|Moderate            |     |Poorly suited      |     |Severe              |
                               | Slope              |0.50 | Slope             |1.00 | Low strength       |1.00
                               | Low strength       |0.50 | Low strength      |0.50 |                    |
                               |                    |     |                   |     |                    |
          913G:                |                    |     |                   |     |                    |
           Marseilles----------|Severe              |     |Poorly suited      |     |Severe              |
                               | Slope              |1.00 | Slope             |1.00 | Low strength       |1.00
                               | Low strength       |0.50 | Low strength      |0.50 |                    |
                               |                    |     |                   |     |                    |
           Hickory-------------|Severe              |     |Poorly suited      |     |Severe              |
                               | Slope              |1.00 | Slope             |1.00 | Low strength       |1.00
                               | Low strength       |0.50 | Low strength      |0.50 |                    |
                               |                    |     |                   |     |                    |
          917C2:               |                    |     |                   |     |                    |
           Oakville------------|Moderate            |     |Moderately suited |      |Moderate            |
                               | Sandiness          |0.50 | Sandiness         |0.50 | Low strength       |0.50
                               |                    |     | Slope             |0.50 |                    |
                               |                    |     |                   |     |                    |
           Tell----------------|Moderate            |     |Moderately suited |      |Severe              |
                               | Low strength       |0.50 | Low strength      |0.50 | Low strength       |1.00
                               |                    |     | Slope             |0.50 |                    |
                               |                    |     |                   |     |                    |
          917D2:               |                    |     |                   |     |                    |
           Oakville------------|Moderate            |     |Poorly suited      |     |Moderate            |
                               | Sandiness          |0.50 | Slope             |1.00 | Low strength       |0.50
                               |                    |     | Sandiness         |0.50 |                    |
                               |                    |     |                   |     |                    |
           Tell----------------|Moderate            |     |Poorly suited      |     |Severe              |
                               | Low strength       |0.50 | Slope             |1.00 | Low strength       |1.00
                               |                    |     | Low strength      |0.50 |                    |
                               |                    |     |                   |     |                    |
          943D2:               |                    |     |                   |     |                    |
           Seaton--------------|Moderate            |     |Poorly suited      |     |Severe              |
                               | Low strength       |0.50 | Slope             |1.00 | Low strength       |1.00
                               |                    |     | Low strength      |0.50 |                    |
                               |                    |     |                   |     |                    |
           Timula--------------|Moderate            |     |Poorly suited      |     |Severe              |
                               | Low strength       |0.50 | Slope             |1.00 | Low strength       |1.00
                               |                    |     | Low strength      |0.50 |                    |
                               |                    |     |                   |     |                    |
          943F2:               |                    |     |                   |     |                    |
           Seaton--------------|Moderate            |     |Poorly suited      |     |Severe              |
                               | Slope              |0.50 | Slope             |1.00 | Low strength       |1.00
                               | Low strength       |0.50 | Low strength      |0.50 |                    |
                               |                    |     |                   |     |                    |
180                                                                                                  Soil Survey of



                                   Table 9a.--Forestland Management--Continued
      ___________________________________________________________________________________________________
                           |                          |                         |
            Map symbol     | Limitations affecting |        Suitability for     |       Soil rutting
          and soil name    |     construction of      |      log landings       |          hazard
                           |     haul roads and       |                         |
                                   log landings       |                         |
                           |_____________________________________________________________________________
                           | Rating class and |Value| Rating class and |Value| Rating class and |Value
                           | limiting features |      | limiting features |     | limiting features |
      ___________________________________________________________________________________________________
                           |                    |     |                   |     |                    |
      943F2:               |                    |     |                   |     |                    |
       Timula--------------|Moderate            |     |Poorly suited      |     |Severe              |
                           | Slope              |0.50 | Slope             |1.00 | Low strength       |1.00
                           | Low strength       |0.50 | Low strength      |0.50 |                    |
                           |                    |     |                   |     |                    |
      946D3:               |                    |     |                   |     |                    |
       Hickory-------------|Moderate            |     |Poorly suited      |     |Severe              |
                           | Low strength       |0.50 | Slope             |1.00 | Low strength       |1.00
                           |                    |     | Low strength      |0.50 |                    |
                           |                    |     |                   |     |                    |
       Atlas---------------|Moderate            |     |Poorly suited      |     |Severe              |
                           | Stickiness/slope |0.50 | Slope               |1.00 | Low strength       |1.00
                           | Low strength       |0.50 | Wetness           |0.50 |                    |
                           |                    |     | Low strength      |0.50 |                    |
                           |                    |     | Stickiness        |0.50 |                    |
                           |                    |     |                   |     |                    |
      946F3:               |                    |     |                   |     |                    |
       Hickory-------------|Moderate            |     |Poorly suited      |     |Severe              |
                           | Slope              |0.50 | Slope             |1.00 | Low strength       |1.00
                           | Low strength       |0.50 | Low strength      |0.50 |                    |
                           |                    |     |                   |     |                    |
       Atlas---------------|Moderate            |     |Poorly suited      |     |Severe              |
                           | Slope              |0.50 | Slope             |1.00 | Low strength       |1.00
                           | Stickiness/slope |0.50 | Wetness             |0.50 |                    |
                           | Low strength       |0.50 | Low strength      |0.50 |                    |
                           |                    |     | Stickiness        |0.50 |                    |
                           |                    |     |                   |     |                    |
      959G:                |                    |     |                   |     |                    |
       Strawn--------------|Severe              |     |Poorly suited      |     |Severe              |
                           | Slope              |1.00 | Slope             |1.00 | Low strength       |1.00
                           | Low strength       |0.50 | Low strength      |0.50 |                    |
                           |                    |     |                   |     |                    |
       Chute---------------|Severe              |     |Poorly suited      |     |Moderate            |
                           | Slope              |1.00 | Slope             |1.00 | Low strength       |0.50
                           |                    |     | Sandiness         |0.50 |                    |
                           |                    |     |                   |     |                    |
      960D2, 960D3:        |                    |     |                   |     |                    |
       Hickory-------------|Moderate            |     |Poorly suited      |     |Severe              |
                           | Low strength       |0.50 | Slope             |1.00 | Low strength       |1.00
                           |                    |     | Low strength      |0.50 |                    |
                           |                    |     |                   |     |                    |
       Sylvan--------------|Moderate            |     |Poorly suited      |     |Severe              |
                           | Low strength       |0.50 | Slope             |1.00 | Low strength       |1.00
                           |                    |     | Low strength      |0.50 |                    |
                           |                    |     |                   |     |                    |
       Fayette-------------|Moderate            |     |Poorly suited      |     |Severe              |
                           | Low strength       |0.50 | Slope             |1.00 | Low strength       |1.00
                           |                    |     | Low strength      |0.50 |                    |
                           |                    |     |                   |     |                    |
      960F:                |                    |     |                   |     |                    |
       Hickory-------------|Moderate            |     |Poorly suited      |     |Severe              |
                           | Slope              |0.50 | Slope             |1.00 | Low strength       |1.00
                           | Low strength       |0.50 | Low strength      |0.50 |                    |
                           |                    |     |                   |     |                    |
       Sylvan--------------|Moderate            |     |Poorly suited      |     |Severe              |
                           | Slope              |0.50 | Slope             |1.00 | Low strength       |1.00
                           | Low strength       |0.50 | Low strength      |0.50 |                    |
                           |                    |     |                   |     |                    |
       Fayette-------------|Moderate            |     |Poorly suited      |     |Severe              |
                           | Slope              |0.50 | Slope             |1.00 | Low strength       |1.00
                           | Low strength       |0.50 | Low strength      |0.50 |                    |
                           |                    |     |                   |     |                    |
Rock Island County, Illinois                                                                                     181



                                      Table 9a.--Forestland Management--Continued
          ___________________________________________________________________________________________________
                               |                          |                         |
                Map symbol     | Limitations affecting |        Suitability for     |       Soil rutting
              and soil name    |     construction of      |      log landings       |          hazard
                               |     haul roads and       |                         |
                                      log landings        |                         |
                               |_____________________________________________________________________________
                               | Rating class and |Value| Rating class and |Value| Rating class and |Value
                               | limiting features |      | limiting features |     | limiting features |
          ___________________________________________________________________________________________________
                               |                    |     |                   |     |                    |
          962F:                |                    |     |                   |     |                    |
           Sylvan--------------|Moderate            |     |Poorly suited      |     |Severe              |
                               | Slope              |0.50 | Slope             |1.00 | Low strength       |1.00
                               | Low strength       |0.50 | Low strength      |0.50 |                    |
                               |                    |     |                   |     |                    |
           Bold----------------|Moderate            |     |Poorly suited      |     |Severe              |
                               | Slope              |0.50 | Slope             |1.00 | Low strength       |1.00
                               | Low strength       |0.50 | Low strength      |0.50 |                    |
                               |                    |     |                   |     |                    |
          ___________________________________________________________________________________________________
182                                                                                                    Soil Survey of



                                          Table 9b.--Forestland Management

      (The information in this table indicates the dominant soil condition but does not eliminate the need
           for onsite investigation. The numbers in the value columns range from 0.01 to 1.00. The larger
           the value, the greater the limitation. See text for further explanation of ratings in this
           table)

      ________________________________________________________________________________________________________
                                |                         |                         |
            Map symbol          |   Hazard of off-road    |    Hazard of erosion    | Suitability for roads
           and soil name        | or off-trail erosion    |   on roads and trails   |    (natural surface)
                                                          |                         |
                                |_____________________________________________________________________________
                                | Rating class and |Value| Rating class and |Value| Rating class and |Value
                                | limiting features |     | limiting features |     | limiting features |
      ________________________________________________________________________________________________________
                                |                   |     |                   |     |                   |
      8D2, 8D3:                 |                   |     |                   |     |                   |
       Hickory------------------|Slight             |     |Severe             |     |Poorly suited      |
                                |                   |     | Slope/erodibility|0.95 | Slope              |1.00
                                |                   |     |                   |     | Low strength      |0.50
                                |                   |     |                   |     |                   |
      8F, 8F3:                  |                   |     |                   |     |                   |
       Hickory------------------|Moderate           |     |Severe             |     |Poorly suited      |
                                | Slope/erodibility|0.50 | Slope/erodibility|0.95 | Slope               |1.00
                                |                   |     |                   |     | Low strength      |0.50
                                |                   |     |                   |     |                   |
      19C3:                     |                   |     |                   |     |                   |
       Sylvan-------------------|Slight             |     |Moderate           |     |Moderately suited |
                                |                   |     | Slope/erodibility|0.50 | Low strength       |0.50
                                |                   |     |                   |     | Slope             |0.50
                                |                   |     |                   |     |                   |
      19D, 19D3:                |                   |     |                   |     |                   |
       Sylvan-------------------|Moderate           |     |Severe             |     |Poorly suited      |
                                | Slope/erodibility|0.50 | Slope/erodibility|0.95 | Slope               |1.00
                                |                   |     |                   |     | Low strength      |0.50
                                |                   |     |                   |     |                   |
      19F, 19F3:                |                   |     |                   |     |                   |
       Sylvan-------------------|Severe             |     |Severe             |     |Poorly suited      |
                                | Slope/erodibility|0.75 | Slope/erodibility|0.95 | Slope               |1.00
                                |                   |     |                   |     | Low strength      |0.50
                                |                   |     |                   |     |                   |
      88A:                      |                   |     |                   |     |                   |
       Sparta-------------------|Slight             |     |Slight             |     |Moderately suited |
                                |                   |     |                   |     | Sandiness         |0.50
                                |                   |     |                   |     |                   |
      274B, 274B2:              |                   |     |                   |     |                   |
       Seaton-------------------|Slight             |     |Moderate           |     |Moderately suited |
                                |                   |     | Slope/erodibility|0.50 | Low strength       |0.50
                                |                   |     |                   |     |                   |
      274C2:                    |                   |     |                   |     |                   |
       Seaton-------------------|Slight             |     |Moderate           |     |Moderately suited |
                                |                   |     | Slope/erodibility|0.50 | Low strength       |0.50
                                |                   |     |                   |     | Slope             |0.50
                                |                   |     |                   |     |                   |
      274D2:                    |                   |     |                   |     |                   |
       Seaton-------------------|Moderate           |     |Severe             |     |Poorly suited      |
                                | Slope/erodibility|0.50 | Slope/erodibility|0.95 | Slope               |1.00
                                |                   |     |                   |     | Low strength      |0.50
                                |                   |     |                   |     |                   |
      278A:                     |                   |     |                   |     |                   |
       Stronghurst--------------|Slight             |     |Slight             |     |Moderately suited |
                                |                   |     |                   |     | Wetness           |0.50
                                |                   |     |                   |     | Low strength      |0.50
                                |                   |     |                   |     |                   |
      279A:                     |                   |     |                   |     |                   |
       Rozetta------------------|Slight             |     |Slight             |     |Moderately suited |
                                |                   |     |                   |     | Low strength      |0.50
                                |                   |     |                   |     |                   |
      279B:                     |                   |     |                   |     |                   |
       Rozetta------------------|Slight             |     |Moderate           |     |Moderately suited |
                                |                   |     | Slope/erodibility|0.50 | Low strength       |0.50
                                |                   |     |                   |     |                   |
Rock Island County, Illinois                                                                                       183



                                       Table 9b.--Forestland Management--Continued
        ________________________________________________________________________________________________________
                                  |                         |                         |
              Map symbol          |   Hazard of off-road    |    Hazard of erosion    | Suitability for roads
            and soil name         | or off-trail erosion    |   on roads and trails   |    (natural surface)
                                                            |                         |
                                  |_____________________________________________________________________________
                                  | Rating class and |Value| Rating class and |Value| Rating class and |Value
                                  | limiting features |     | limiting features |     | limiting features |
        ________________________________________________________________________________________________________
                                  |                   |     |                   |     |                   |
        280B, 280B2:              |                   |     |                   |     |                   |
         Fayette------------------|Slight             |     |Moderate           |     |Moderately suited |
                                  |                   |     | Slope/erodibility|0.50 | Low strength       |0.50
                                  |                   |     |                   |     |                   |
        280C2, 280C3:             |                   |     |                   |     |                   |
         Fayette------------------|Slight             |     |Moderate           |     |Moderately suited |
                                  |                   |     | Slope/erodibility|0.50 | Low strength       |0.50
                                  |                   |     |                   |     | Slope             |0.50
                                  |                   |     |                   |     |                   |
        570B:                     |                   |     |                   |     |                   |
         Martinsville-------------|Slight             |     |Moderate           |     |Moderately suited |
                                  |                   |     | Slope/erodibility|0.50 | Low strength       |0.50
                                  |                   |     |                   |     |                   |
        570C3:                    |                   |     |                   |     |                   |
         Martinsville-------------|Slight             |     |Moderate           |     |Moderately suited |
                                  |                   |     | Slope/erodibility|0.50 | Low strength       |0.50
                                  |                   |     |                   |     | Slope             |0.50
                                  |                   |     |                   |     |                   |
        570D3:                    |                   |     |                   |     |                   |
         Martinsville-------------|Slight             |     |Severe             |     |Poorly suited      |
                                  |                   |     | Slope/erodibility|0.95 | Slope              |1.00
                                  |                   |     |                   |     | Low strength      |0.50
                                  |                   |     |                   |     |                   |
        689B:                     |                   |     |                   |     |                   |
         Coloma-------------------|Slight             |     |Slight             |     |Moderately suited |
                                  |                   |     |                   |     | Sandiness         |0.50
                                  |                   |     |                   |     |                   |
        689D:                     |                   |     |                   |     |                   |
         Coloma-------------------|Slight             |     |Moderate           |     |Moderately suited |
                                  |                   |     | Slope/erodibility|0.50 | Slope              |0.50
                                  |                   |     |                   |     | Sandiness         |0.50
                                  |                   |     |                   |     |                   |
        898F3:                    |                   |     |                   |     |                   |
         Hickory------------------|Moderate           |     |Severe             |     |Poorly suited      |
                                  | Slope/erodibility|0.50 | Slope/erodibility|0.95 | Slope               |1.00
                                  |                   |     |                   |     | Low strength      |0.50
                                  |                   |     |                   |     |                   |
         Sylvan-------------------|Severe             |     |Severe             |     |Poorly suited      |
                                  | Slope/erodibility|0.75 | Slope/erodibility|0.95 | Slope               |1.00
                                  |                   |     |                   |     | Low strength      |0.50
                                  |                   |     |                   |     |                   |
        898G:                     |                   |     |                   |     |                   |
         Hickory------------------|Severe             |     |Severe             |     |Poorly suited      |
                                  | Slope/erodibility|0.75 | Slope/erodibility|0.95 | Slope               |1.00
                                  |                   |     |                   |     | Low strength      |0.50
                                  |                   |     |                   |     |                   |
         Sylvan-------------------|Very severe        |     |Severe             |     |Poorly suited      |
                                  | Slope/erodibility|0.95 | Slope/erodibility|0.95 | Slope               |1.00
                                  |                   |     |                   |     | Low strength      |0.50
                                  |                   |     |                   |     |                   |
        913D2:                    |                   |     |                   |     |                   |
         Marseilles---------------|Slight             |     |Severe             |     |Poorly suited      |
                                  |                   |     | Slope/erodibility|0.95 | Slope              |1.00
                                  |                   |     |                   |     | Low strength      |0.50
                                  |                   |     |                   |     |                   |
         Hickory------------------|Slight             |     |Severe             |     |Poorly suited      |
                                  |                   |     | Slope/erodibility|0.95 | Slope              |1.00
                                  |                   |     |                   |     | Low strength      |0.50
                                  |                   |     |                   |     |                   |
184                                                                                                    Soil Survey of



                                     Table 9b.--Forestland Management--Continued
      ________________________________________________________________________________________________________
                                |                         |                         |
            Map symbol          |   Hazard of off-road    |    Hazard of erosion    | Suitability for roads
          and soil name         | or off-trail erosion    |   on roads and trails   |    (natural surface)
                                                          |                         |
                                |_____________________________________________________________________________
                                | Rating class and |Value| Rating class and |Value| Rating class and |Value
                                | limiting features |     | limiting features |     | limiting features |
      ________________________________________________________________________________________________________
                                |                   |     |                   |     |                   |
      913F:                     |                   |     |                   |     |                   |
       Marseilles---------------|Moderate           |     |Severe             |     |Poorly suited      |
                                | Slope/erodibility|0.50 | Slope/erodibility|0.95 | Slope               |1.00
                                |                   |     |                   |     | Low strength      |0.50
                                |                   |     |                   |     |                   |
       Hickory------------------|Moderate           |     |Severe             |     |Poorly suited      |
                                | Slope/erodibility|0.50 | Slope/erodibility|0.95 | Slope               |1.00
                                |                   |     |                   |     | Low strength      |0.50
                                |                   |     |                   |     |                   |
      913G:                     |                   |     |                   |     |                   |
       Marseilles---------------|Severe             |     |Severe             |     |Poorly suited      |
                                | Slope/erodibility|0.75 | Slope/erodibility|0.95 | Slope               |1.00
                                |                   |     |                   |     | Low strength      |0.50
                                |                   |     |                   |     |                   |
       Hickory------------------|Severe             |     |Severe             |     |Poorly suited      |
                                | Slope/erodibility|0.75 | Slope/erodibility|0.95 | Slope               |1.00
                                |                   |     |                   |     | Low strength      |0.50
                                |                   |     |                   |     |                   |
      917C2:                    |                   |     |                   |     |                   |
       Oakville-----------------|Slight             |     |Moderate           |     |Moderately suited |
                                |                   |     | Slope/erodibility|0.50 | Sandiness          |0.50
                                |                   |     |                   |     | Slope             |0.50
                                |                   |     |                   |     |                   |
       Tell---------------------|Slight             |     |Moderate           |     |Moderately suited |
                                |                   |     | Slope/erodibility|0.50 | Low strength       |0.50
                                |                   |     |                   |     | Slope             |0.50
                                |                   |     |                   |     |                   |
      917D2:                    |                   |     |                   |     |                   |
       Oakville-----------------|Slight             |     |Moderate           |     |Poorly suited      |
                                |                   |     | Slope/erodibility|0.50 | Slope              |1.00
                                |                   |     |                   |     | Sandiness         |0.50
                                |                   |     |                   |     |                   |
       Tell---------------------|Moderate           |     |Severe             |     |Poorly suited      |
                                | Slope/erodibility|0.50 | Slope/erodibility|0.95 | Slope               |1.00
                                |                   |     |                   |     | Low strength      |0.50
                                |                   |     |                   |     |                   |
      943D2:                    |                   |     |                   |     |                   |
       Seaton-------------------|Moderate           |     |Severe             |     |Poorly suited      |
                                | Slope/erodibility|0.50 | Slope/erodibility|0.95 | Slope               |1.00
                                |                   |     |                   |     | Low strength      |0.50
                                |                   |     |                   |     |                   |
       Timula-------------------|Moderate           |     |Severe             |     |Poorly suited      |
                                | Slope/erodibility|0.50 | Slope/erodibility|0.95 | Slope               |1.00
                                |                   |     |                   |     | Low strength      |0.50
                                |                   |     |                   |     |                   |
      943F2:                    |                   |     |                   |     |                   |
       Seaton-------------------|Severe             |     |Severe             |     |Poorly suited      |
                                | Slope/erodibility|0.75 | Slope/erodibility|0.95 | Slope               |1.00
                                |                   |     |                   |     | Low strength      |0.50
                                |                   |     |                   |     |                   |
       Timula-------------------|Severe             |     |Severe             |     |Poorly suited      |
                                | Slope/erodibility|0.75 | Slope/erodibility|0.95 | Slope               |1.00
                                |                   |     |                   |     | Low strength      |0.50
                                |                   |     |                   |     |                   |
      946D3:                    |                   |     |                   |     |                   |
       Hickory------------------|Slight             |     |Severe             |     |Poorly suited      |
                                |                   |     | Slope/erodibility|0.95 | Slope              |1.00
                                |                   |     |                   |     | Low strength      |0.50
                                |                   |     |                   |     |                   |
Rock Island County, Illinois                                                                                       185



                                       Table 9b.--Forestland Management--Continued
        ________________________________________________________________________________________________________
                                  |                         |                         |
              Map symbol          |   Hazard of off-road    |    Hazard of erosion    | Suitability for roads
            and soil name         | or off-trail erosion    |   on roads and trails   |    (natural surface)
                                                            |                         |
                                  |_____________________________________________________________________________
                                  | Rating class and |Value| Rating class and |Value| Rating class and |Value
                                  | limiting features |     | limiting features |     | limiting features |
        ________________________________________________________________________________________________________
                                  |                   |     |                   |     |                   |
        946D3:                    |                   |     |                   |     |                   |
         Atlas--------------------|Moderate           |     |Severe             |     |Poorly suited      |
                                  | Slope/erodibility|0.50 | Slope/erodibility|0.95 | Slope               |1.00
                                  |                   |     |                   |     | Wetness           |0.50
                                  |                   |     |                   |     | Low strength      |0.50
                                  |                   |     |                   |     | Stickiness        |0.50
                                  |                   |     |                   |     |                   |
        946F3:                    |                   |     |                   |     |                   |
         Hickory------------------|Moderate           |     |Severe             |     |Poorly suited      |
                                  | Slope/erodibility|0.50 | Slope/erodibility|0.95 | Slope               |1.00
                                  |                   |     |                   |     | Low strength      |0.50
                                  |                   |     |                   |     |                   |
         Atlas--------------------|Severe             |     |Severe             |     |Poorly suited      |
                                  | Slope/erodibility|0.75 | Slope/erodibility|0.95 | Slope               |1.00
                                  |                   |     |                   |     | Wetness           |0.50
                                  |                   |     |                   |     | Low strength      |0.50
                                  |                   |     |                   |     | Stickiness        |0.50
                                  |                   |     |                   |     |                   |
        959G:                     |                   |     |                   |     |                   |
         Strawn-------------------|Severe             |     |Severe             |     |Poorly suited      |
                                  | Slope/erodibility|0.75 | Slope/erodibility|0.95 | Slope               |1.00
                                  |                   |     |                   |     | Low strength      |0.50
                                  |                   |     |                   |     |                   |
         Chute--------------------|Severe             |     |Severe             |     |Poorly suited      |
                                  | Slope/erodibility|0.75 | Slope/erodibility|0.95 | Slope               |1.00
                                  |                   |     |                   |     | Sandiness         |0.50
                                  |                   |     |                   |     |                   |
        960D2, 960D3:             |                   |     |                   |     |                   |
         Hickory------------------|Slight             |     |Severe             |     |Poorly suited      |
                                  |                   |     | Slope/erodibility|0.95 | Slope              |1.00
                                  |                   |     |                   |     | Low strength      |0.50
                                  |                   |     |                   |     |                   |
         Sylvan-------------------|Moderate           |     |Severe             |     |Poorly suited      |
                                  | Slope/erodibility|0.50 | Slope/erodibility|0.95 | Slope               |1.00
                                  |                   |     |                   |     | Low strength      |0.50
                                  |                   |     |                   |     |                   |
         Fayette------------------|Moderate           |     |Severe             |     |Poorly suited      |
                                  | Slope/erodibility|0.50 | Slope/erodibility|0.95 | Slope               |1.00
                                  |                   |     |                   |     | Low strength      |0.50
                                  |                   |     |                   |     |                   |
        960F:                     |                   |     |                   |     |                   |
         Hickory------------------|Moderate           |     |Severe             |     |Poorly suited      |
                                  | Slope/erodibility|0.50 | Slope/erodibility|0.95 | Slope               |1.00
                                  |                   |     |                   |     | Low strength      |0.50
                                  |                   |     |                   |     |                   |
         Sylvan-------------------|Severe             |     |Severe             |     |Poorly suited      |
                                  | Slope/erodibility|0.75 | Slope/erodibility|0.95 | Slope               |1.00
                                  |                   |     |                   |     | Low strength      |0.50
                                  |                   |     |                   |     |                   |
         Fayette------------------|Severe             |     |Severe             |     |Poorly suited      |
                                  | Slope/erodibility|0.75 | Slope/erodibility|0.95 | Slope               |1.00
                                  |                   |     |                   |     | Low strength      |0.50
                                  |                   |     |                   |     |                   |
        962F:                     |                   |     |                   |     |                   |
         Sylvan-------------------|Severe             |     |Severe             |     |Poorly suited      |
                                  | Slope/erodibility|0.75 | Slope/erodibility|0.95 | Slope               |1.00
                                  |                   |     |                   |     | Low strength      |0.50
                                  |                   |     |                   |     |                   |
186                                                                                                    Soil Survey of



                                     Table 9b.--Forestland Management--Continued
      ________________________________________________________________________________________________________
                                |                         |                         |
            Map symbol          |   Hazard of off-road    |    Hazard of erosion    | Suitability for roads
          and soil name         | or off-trail erosion    |   on roads and trails   |    (natural surface)
                                                          |                         |
                                |_____________________________________________________________________________
                                | Rating class and |Value| Rating class and |Value| Rating class and |Value
                                | limiting features |     | limiting features |     | limiting features |
      ________________________________________________________________________________________________________
                                |                   |     |                   |     |                   |
      962F:                     |                   |     |                   |     |                   |
       Bold---------------------|Severe             |     |Severe             |     |Poorly suited      |
                                | Slope/erodibility|0.75 | Slope/erodibility|0.95 | Slope               |1.00
                                |                   |     |                   |     | Low strength      |0.50
                                |                   |     |                   |     |                   |
      ________________________________________________________________________________________________________
Rock Island County, Illinois                                                                                    187



                                           Table 9c.--Forestland Management

          (Only the soils suitable for production of commercial trees are listed. The information in this
               table indicates the dominant soil condition but does not eliminate the need for onsite
               investigation. The numbers in the value columns range from 0.01 to 1.00. The larger the value,
               the greater the limitation. See text for further explanation of ratings in this table)

          ___________________________________________________________________________________________________
                               |                          |                         |
                Map symbol     |     Suitability for      |     Suitability for     | Suitability for use of
               and soil name   |      hand planting       |   mechanical planting   | harvesting equipment
                               |                          |                         |
                                                          |                         |
                               |_____________________________________________________________________________
                               | Rating class and |Value| Rating class and |Value| Rating class and |Value
                               | limiting features |      | limiting features |     | limiting features |
          ___________________________________________________________________________________________________
                               |                    |     |                   |     |                   |
          8D2, 8D3:            |                    |     |                   |     |                   |
           Hickory-------------|Moderately suited |       |Moderately suited |      |Moderately suited |
                               | Stickiness         |0.50 | Slope             |0.50 | Low strength      |0.50
                               |                    |     | Stickiness        |0.50 |                   |
                               |                    |     |                   |     |                   |
          8F, 8F3:             |                    |     |                   |     |                   |
           Hickory-------------|Moderately suited |       |Unsuited           |     |Moderately suited |
                               | Stickiness         |0.50 | Slope             |1.00 | Low strength      |0.50
                               |                    |     | Stickiness        |0.50 | Slope             |0.50
                               |                    |     |                   |     |                   |
          19C3, 19D, 19D3:     |                    |     |                   |     |                   |
           Sylvan--------------|Moderately suited |       |Moderately suited |      |Moderately suited |
                               | Stickiness         |0.50 | Slope             |0.50 | Low strength      |0.50
                               |                    |     | Stickiness        |0.50 |                   |
                               |                    |     |                   |     |                   |
          19F, 19F3:           |                    |     |                   |     |                   |
           Sylvan--------------|Moderately suited |       |Unsuited           |     |Moderately suited |
                               | Stickiness         |0.50 | Slope             |1.00 | Low strength      |0.50
                               |                    |     | Stickiness        |0.50 | Slope             |0.50
                               |                    |     |                   |     |                   |
          88A:                 |                    |     |                   |     |                   |
           Sparta--------------|Moderately suited |       |Moderately suited |      |Moderately suited |
                               | Sandiness          |0.50 | Sandiness         |0.50 | Sandiness         |0.50
                               |                    |     |                   |     |                   |
          274B, 274B2:         |                    |     |                   |     |                   |
           Seaton--------------|Well suited         |     |Well suited        |     |Moderately suited |
                               |                    |     |                   |     | Low strength      |0.50
                               |                    |     |                   |     |                   |
          274C2, 274D2:        |                    |     |                   |     |                   |
           Seaton--------------|Well suited         |     |Moderately suited |      |Moderately suited |
                               |                    |     | Slope             |0.50 | Low strength      |0.50
                               |                    |     |                   |     |                   |
          278A:                |                    |     |                   |     |                   |
           Stronghurst---------|Moderately suited |       |Moderately suited |      |Moderately suited |
                               | Stickiness         |0.50 | Stickiness        |0.50 | Low strength      |0.50
                               |                    |     |                   |     |                   |
          279A, 279B:          |                    |     |                   |     |                   |
           Rozetta-------------|Moderately suited |       |Moderately suited |      |Moderately suited |
                               | Stickiness         |0.50 | Stickiness        |0.50 | Low strength      |0.50
                               |                    |     |                   |     |                   |
          280B, 280B2:         |                    |     |                   |     |                   |
           Fayette-------------|Moderately suited |       |Moderately suited |      |Moderately suited |
                               | Stickiness         |0.50 | Stickiness        |0.50 | Low strength      |0.50
                               |                    |     |                   |     |                   |
          280C2, 280C3:        |                    |     |                   |     |                   |
           Fayette-------------|Moderately suited |       |Moderately suited |      |Moderately suited |
                               | Stickiness         |0.50 | Slope             |0.50 | Low strength      |0.50
                               |                    |     | Stickiness        |0.50 |                   |
                               |                    |     |                   |     |                   |
          570B:                |                    |     |                   |     |                   |
           Martinsville--------|Moderately suited |       |Moderately suited |      |Moderately suited |
                               | Stickiness         |0.50 | Stickiness        |0.50 | Low strength      |0.50
                               |                    |     |                   |     |                   |
188                                                                                                 Soil Survey of



                                  Table 9c.--Forestland Management--Continued
      ___________________________________________________________________________________________________
                           |                          |                         |
            Map symbol     |     Suitability for      |     Suitability for     | Suitability for use of
          and soil name    |      hand planting       |   mechanical planting   | harvesting equipment
                           |                          |                         |
                                                      |                         |
                           |_____________________________________________________________________________
                           | Rating class and |Value| Rating class and |Value| Rating class and |Value
                           | limiting features |      | limiting features |     | limiting features |
      ___________________________________________________________________________________________________
                           |                    |     |                   |     |                   |
      570C3, 570D3:        |                    |     |                   |     |                   |
       Martinsville--------|Moderately suited |       |Moderately suited |      |Moderately suited |
                           | Stickiness         |0.50 | Slope             |0.50 | Low strength      |0.50
                           |                    |     | Stickiness        |0.50 |                   |
                           |                    |     |                   |     |                   |
      689B:                |                    |     |                   |     |                   |
       Coloma--------------|Moderately suited |       |Moderately suited |      |Moderately suited |
                           | Sandiness          |0.50 | Sandiness         |0.50 | Sandiness         |0.50
                           |                    |     |                   |     |                   |
      689D:                |                    |     |                   |     |                   |
       Coloma--------------|Moderately suited |       |Moderately suited |      |Moderately suited |
                           | Sandiness          |0.50 | Slope             |0.50 | Sandiness         |0.50
                           |                    |     | Sandiness         |0.50 |                   |
                           |                    |     |                   |     |                   |
      741F:                |                    |     |                   |     |                   |
       Oakville------------|Moderately suited |       |Poorly suited      |     |Moderately suited |
                           | Sandiness          |0.50 | Slope             |0.75 | Sandiness         |0.50
                           |                    |     | Sandiness         |0.50 | Slope             |0.50
                           |                    |     |                   |     |                   |
      898F3:               |                    |     |                   |     |                   |
       Hickory-------------|Moderately suited |       |Unsuited           |     |Moderately suited |
                           | Stickiness         |0.50 | Slope             |1.00 | Low strength      |0.50
                           |                    |     | Stickiness        |0.50 | Slope             |0.50
                           |                    |     |                   |     |                   |
       Sylvan--------------|Moderately suited |       |Unsuited           |     |Moderately suited |
                           | Stickiness         |0.50 | Slope             |1.00 | Low strength      |0.50
                           |                    |     | Stickiness        |0.50 | Slope             |0.50
                           |                    |     |                   |     |                   |
      898G:                |                    |     |                   |     |                   |
       Hickory-------------|Moderately suited |       |Unsuited           |     |Poorly suited      |
                           | Slope              |0.50 | Slope             |1.00 | Slope             |1.00
                           | Stickiness         |0.50 | Stickiness        |0.50 | Low strength      |0.50
                           |                    |     |                   |     |                   |
       Sylvan--------------|Moderately suited |       |Unsuited           |     |Poorly suited      |
                           | Slope              |0.50 | Slope             |1.00 | Slope             |1.00
                           | Stickiness         |0.50 | Stickiness        |0.50 | Low strength      |0.50
                           |                    |     |                   |     |                   |
      913D2:               |                    |     |                   |     |                   |
       Marseilles----------|Moderately suited |       |Moderately suited |      |Moderately suited |
                           | Stickiness         |0.50 | Slope             |0.50 | Low strength      |0.50
                           |                    |     | Stickiness        |0.50 |                   |
                           |                    |     |                   |     |                   |
       Hickory-------------|Moderately suited |       |Moderately suited |      |Moderately suited |
                           | Stickiness         |0.50 | Slope             |0.50 | Low strength      |0.50
                           |                    |     | Stickiness        |0.50 |                   |
                           |                    |     |                   |     |                   |
      913F:                |                    |     |                   |     |                   |
       Marseilles----------|Moderately suited |       |Unsuited           |     |Moderately suited |
                           | Stickiness         |0.50 | Slope             |1.00 | Low strength      |0.50
                           |                    |     | Stickiness        |0.50 | Slope             |0.50
                           |                    |     |                   |     |                   |
       Hickory-------------|Moderately suited |       |Unsuited           |     |Moderately suited |
                           | Stickiness         |0.50 | Slope             |1.00 | Low strength      |0.50
                           |                    |     | Stickiness        |0.50 | Slope             |0.50
                           |                    |     |                   |     |                   |
      913G:                |                    |     |                   |     |                   |
       Marseilles----------|Moderately suited |       |Unsuited           |     |Poorly suited      |
                           | Slope              |0.50 | Slope             |1.00 | Slope             |1.00
                           | Stickiness         |0.50 | Stickiness        |0.50 | Low strength      |0.50
                           |                    |     |                   |     |                   |
Rock Island County, Illinois                                                                                    189



                                      Table 9c.--Forestland Management--Continued
          ___________________________________________________________________________________________________
                               |                          |                         |
                Map symbol     |     Suitability for      |     Suitability for     | Suitability for use of
              and soil name    |      hand planting       |   mechanical planting   | harvesting equipment
                               |                          |                         |
                                                          |                         |
                               |_____________________________________________________________________________
                               | Rating class and |Value| Rating class and |Value| Rating class and |Value
                               | limiting features |      | limiting features |     | limiting features |
          ___________________________________________________________________________________________________
                               |                    |     |                   |     |                   |
          913G:                |                    |     |                   |     |                   |
           Hickory-------------|Moderately suited |       |Unsuited           |     |Poorly suited      |
                               | Slope              |0.50 | Slope             |1.00 | Slope             |1.00
                               | Stickiness         |0.50 | Stickiness        |0.50 | Low strength      |0.50
                               |                    |     |                   |     |                   |
          917C2, 917D2:        |                    |     |                   |     |                   |
           Oakville------------|Moderately suited |       |Moderately suited |      |Moderately suited |
                               | Sandiness          |0.50 | Slope             |0.50 | Sandiness         |0.50
                               |                    |     | Sandiness         |0.50 |                   |
                               |                    |     |                   |     |                   |
           Tell----------------|Well suited         |     |Moderately suited |      |Moderately suited |
                               |                    |     | Slope             |0.50 | Low strength      |0.50
                               |                    |     |                   |     |                   |
          943D2:               |                    |     |                   |     |                   |
           Seaton--------------|Well suited         |     |Moderately suited |      |Moderately suited |
                               |                    |     | Slope             |0.50 | Low strength      |0.50
                               |                    |     |                   |     |                   |
           Timula--------------|Well suited         |     |Moderately suited |      |Moderately suited |
                               |                    |     | Slope             |0.50 | Low strength      |0.50
                               |                    |     |                   |     |                   |
          943F2:               |                    |     |                   |     |                   |
           Seaton--------------|Well suited         |     |Unsuited           |     |Moderately suited |
                               |                    |     | Slope             |1.00 | Low strength      |0.50
                               |                    |     |                   |     | Slope             |0.50
                               |                    |     |                   |     |                   |
           Timula--------------|Well suited         |     |Unsuited           |     |Moderately suited |
                               |                    |     | Slope             |1.00 | Low strength      |0.50
                               |                    |     |                   |     | Slope             |0.50
                               |                    |     |                   |     |                   |
          946D3:               |                    |     |                   |     |                   |
           Hickory-------------|Moderately suited |       |Moderately suited |      |Moderately suited |
                               | Stickiness         |0.50 | Slope             |0.50 | Low strength      |0.50
                               |                    |     | Stickiness        |0.50 |                   |
                               |                    |     |                   |     |                   |
           Atlas---------------|Poorly suited       |     |Poorly suited      |     |Moderately suited |
                               | Stickiness         |0.75 | Stickiness        |0.75 | Low strength      |0.50
                               |                    |     | Slope             |0.50 | Stickiness        |0.50
                               |                    |     |                   |     |                   |
          946F3:               |                    |     |                   |     |                   |
           Hickory-------------|Moderately suited |       |Unsuited           |     |Moderately suited |
                               | Stickiness         |0.50 | Slope             |1.00 | Low strength      |0.50
                               |                    |     | Stickiness        |0.50 | Slope             |0.50
                               |                    |     |                   |     |                   |
           Atlas---------------|Poorly suited       |     |Unsuited           |     |Moderately suited |
                               | Stickiness         |0.75 | Slope             |1.00 | Low strength      |0.50
                               |                    |     | Stickiness        |0.75 | Slope             |0.50
                               |                    |     |                   |     | Stickiness        |0.50
                               |                    |     |                   |     |                   |
          959G:                |                    |     |                   |     |                   |
           Strawn--------------|Moderately suited |       |Unsuited           |     |Poorly suited      |
                               | Slope              |0.50 | Slope             |1.00 | Slope             |1.00
                               |                    |     |                   |     | Low strength      |0.50
                               |                    |     |                   |     |                   |
           Chute---------------|Moderately suited |       |Unsuited           |     |Poorly suited      |
                               | Sandiness          |0.50 | Slope             |1.00 | Slope             |1.00
                               | Slope              |0.50 | Sandiness         |0.50 | Sandiness         |0.50
                               |                    |     |                   |     |                   |
          960D2, 960D3:        |                    |     |                   |     |                   |
           Hickory-------------|Moderately suited |       |Moderately suited |      |Moderately suited |
                               | Stickiness         |0.50 | Slope             |0.50 | Low strength      |0.50
                               |                    |     | Stickiness        |0.50 |                   |
                               |                    |     |                   |     |                   |
190                                                                                                 Soil Survey of



                                  Table 9c.--Forestland Management--Continued
      ___________________________________________________________________________________________________
                           |                          |                         |
            Map symbol     |     Suitability for      |     Suitability for     | Suitability for use of
          and soil name    |      hand planting       |   mechanical planting   | harvesting equipment
                           |                          |                         |
                                                      |                         |
                           |_____________________________________________________________________________
                           | Rating class and |Value| Rating class and |Value| Rating class and |Value
                           | limiting features |      | limiting features |     | limiting features |
      ___________________________________________________________________________________________________
                           |                    |     |                   |     |                   |
      960D2, 960D3:        |                    |     |                   |     |                   |
       Sylvan--------------|Moderately suited |       |Moderately suited |      |Moderately suited |
                           | Stickiness         |0.50 | Slope             |0.50 | Low strength      |0.50
                           |                    |     | Stickiness        |0.50 |                   |
                           |                    |     |                   |     |                   |
       Fayette-------------|Moderately suited |       |Moderately suited |      |Moderately suited |
                           | Stickiness         |0.50 | Slope             |0.50 | Low strength      |0.50
                           |                    |     | Stickiness        |0.50 |                   |
                           |                    |     |                   |     |                   |
      960F:                |                    |     |                   |     |                   |
       Hickory-------------|Moderately suited |       |Unsuited           |     |Moderately suited |
                           | Stickiness         |0.50 | Slope             |1.00 | Low strength      |0.50
                           |                    |     | Stickiness        |0.50 | Slope             |0.50
                           |                    |     |                   |     |                   |
       Sylvan--------------|Moderately suited |       |Unsuited           |     |Moderately suited |
                           | Stickiness         |0.50 | Slope             |1.00 | Low strength      |0.50
                           |                    |     | Stickiness        |0.50 | Slope             |0.50
                           |                    |     |                   |     |                   |
       Fayette-------------|Moderately suited |       |Unsuited           |     |Moderately suited |
                           | Stickiness         |0.50 | Slope             |1.00 | Low strength      |0.50
                           |                    |     | Stickiness        |0.50 | Slope             |0.50
                           |                    |     |                   |     |                   |
      962F:                |                    |     |                   |     |                   |
       Sylvan--------------|Moderately suited |       |Unsuited           |     |Moderately suited |
                           | Stickiness         |0.50 | Slope             |1.00 | Low strength      |0.50
                           |                    |     | Stickiness        |0.50 | Slope             |0.50
                           |                    |     |                   |     |                   |
       Bold----------------|Well suited         |     |Unsuited           |     |Moderately suited |
                           |                    |     | Slope             |1.00 | Low strength      |0.50
                           |                    |     |                   |     | Slope             |0.50
                           |                    |     |                   |     |                   |
      ___________________________________________________________________________________________________
Rock Island County, Illinois                                                                       191



                                           Table 9d.--Forestland Management

                       (Only the soils suitable for production of commercial trees are listed.
                            The information in this table indicates the dominant soil condition
                            but does not eliminate the need for onsite investigation. The
                            numbers in the value columns range from 0.01 to 1.00. The larger the
                            value, the greater the limitation. See text for further explanation
                            of ratings in this table)

                       _________________________________________________________________________
                                            |                         |
                             Map symbol     |     Suitability for     |     Suitability for
                            and soil name   |     mechanical site     |     mechanical site
                                            | preparation (surface) |     preparation (deep)
                                                                      |
                                            |___________________________________________________
                                            | Rating class and |Value| Rating class and |Value
                                            | limiting features |     | limiting features |
                       _________________________________________________________________________
                                            |                   |     |                   |
                       8D2, 8D3:            |                   |     |                   |
                        Hickory-------------|Well suited        |     |Well suited        |
                                            |                   |     |                   |
                       8F, 8F3:             |                   |     |                   |
                        Hickory-------------|Poorly suited      |     |Poorly suited      |
                                            | Slope             |0.50 | Slope             |0.50
                                            |                   |     |                   |
                       19C3, 19D, 19D3:     |                   |     |                   |
                        Sylvan--------------|Well suited        |     |Well suited        |
                                            |                   |     |                   |
                       19F, 19F3:           |                   |     |                   |
                        Sylvan--------------|Poorly suited      |     |Poorly suited      |
                                            | Slope             |0.50 | Slope             |0.50
                                            |                   |     |                   |
                       88A:                 |                   |     |                   |
                        Sparta--------------|Well suited        |     |Well suited        |
                                            |                   |     |                   |
                       274B, 274B2, 274C2, |                    |     |                   |
                        274D2:              |                   |     |                   |
                         Seaton-------------|Well suited        |     |Well suited        |
                                            |                   |     |                   |
                       278A:                |                   |     |                   |
                        Stronghurst---------|Well suited        |     |Well suited        |
                                            |                   |     |                   |
                       279A, 279B:          |                   |     |                   |
                        Rozetta-------------|Well suited        |     |Well suited        |
                                            |                   |     |                   |
                       280B, 280B2, 280C2, |                    |     |                   |
                        280C3:              |                   |     |                   |
                         Fayette------------|Well suited        |     |Well suited        |
                                            |                   |     |                   |
                       570B, 570C3, 570D3: |                    |     |                   |
                        Martinsville--------|Well suited        |     |Well suited        |
                                            |                   |     |                   |
                       689B, 689D:          |                   |     |                   |
                        Coloma--------------|Well suited        |     |Well suited        |
                                            |                   |     |                   |
                       741F:                |                   |     |                   |
                        Oakville------------|Poorly suited      |     |Poorly suited      |
                                            | Slope             |0.50 | Slope             |0.50
                                            |                   |     |                   |
                       898F3:               |                   |     |                   |
                        Hickory-------------|Poorly suited      |     |Poorly suited      |
                                            | Slope             |0.50 | Slope             |0.50
                                            |                   |     |                   |
                        Sylvan--------------|Poorly suited      |     |Poorly suited      |
                                            | Slope             |0.50 | Slope             |0.50
                                            |                   |     |                   |
192                                                                                 Soil Survey of



                       Table 9d.--Forestland Management--Continued
      _________________________________________________________________________
                             |                         |
            Map symbol       |     Suitability for     |     Suitability for
          and soil name      |     mechanical site     |     mechanical site
                             | preparation (surface) |     preparation (deep)
                                                       |
                             |___________________________________________________
                             | Rating class and |Value| Rating class and |Value
                             | limiting features |     | limiting features |
      _________________________________________________________________________
                             |                   |     |                   |
      898G:                  |                   |     |                   |
       Hickory-------------|Unsuited             |     |Unsuited           |
                             | Slope             |1.00 | Slope             |1.00
                             |                   |     |                   |
       Sylvan--------------|Unsuited             |     |Unsuited           |
                             | Slope             |1.00 | Slope             |1.00
                             |                   |     |                   |
      913D2:                 |                   |     |                   |
       Marseilles----------|Well suited          |     |Well suited        |
                             |                   |     |                   |
       Hickory-------------|Well suited          |     |Well suited        |
                             |                   |     |                   |
      913F:                  |                   |     |                   |
       Marseilles----------|Poorly suited        |     |Poorly suited      |
                             | Slope             |0.50 | Slope             |0.50
                             |                   |     |                   |
       Hickory-------------|Poorly suited        |     |Poorly suited      |
                             | Slope             |0.50 | Slope             |0.50
                             |                   |     |                   |
      913G:                  |                   |     |                   |
       Marseilles----------|Unsuited             |     |Unsuited           |
                             | Slope             |1.00 | Slope             |1.00
                             |                   |     |                   |
       Hickory-------------|Unsuited             |     |Unsuited           |
                             | Slope             |1.00 | Slope             |1.00
                             |                   |     |                   |
      917C2, 917D2:          |                   |     |                   |
       Oakville------------|Well suited          |     |Well suited        |
                             |                   |     |                   |
       Tell----------------|Well suited          |     |Well suited        |
                             |                   |     |                   |
      943D2:                 |                   |     |                   |
       Seaton--------------|Well suited          |     |Well suited        |
                             |                   |     |                   |
       Timula--------------|Well suited          |     |Well suited        |
                             |                   |     |                   |
      943F2:                 |                   |     |                   |
       Seaton--------------|Poorly suited        |     |Poorly suited      |
                             | Slope             |0.50 | Slope             |0.50
                             |                   |     |                   |
       Timula--------------|Poorly suited        |     |Poorly suited      |
                             | Slope             |0.50 | Slope             |0.50
                             |                   |     |                   |
      946D3:                 |                   |     |                   |
       Hickory-------------|Well suited          |     |Well suited        |
                             |                   |     |                   |
       Atlas---------------|Poorly suited        |     |Well suited        |
                             | Stickiness        |0.50 |                   |
                             |                   |     |                   |
      946F3:                 |                   |     |                   |
       Hickory-------------|Poorly suited        |     |Poorly suited      |
                             | Slope             |0.50 | Slope             |0.50
                             |                   |     |                   |
       Atlas---------------|Poorly suited        |     |Poorly suited      |
                             | Slope             |0.50 | Slope             |0.50
                             | Stickiness        |0.50 |                   |
                             |                   |     |                   |
Rock Island County, Illinois                                                                         193



                                        Table 9d.--Forestland Management--Continued
                       _________________________________________________________________________
                                              |                         |
                             Map symbol       |     Suitability for     |     Suitability for
                           and soil name      |     mechanical site     |     mechanical site
                                              | preparation (surface) |     preparation (deep)
                                                                        |
                                              |___________________________________________________
                                              | Rating class and |Value| Rating class and |Value
                                              | limiting features |     | limiting features |
                       _________________________________________________________________________
                                              |                   |     |                   |
                       959G:                  |                   |     |                   |
                        Strawn--------------|Unsuited             |     |Unsuited           |
                                              | Slope             |1.00 | Slope             |1.00
                                              |                   |     |                   |
                        Chute---------------|Unsuited             |     |Unsuited           |
                                              | Slope             |1.00 | Slope             |1.00
                                              |                   |     |                   |
                       960D2, 960D3:          |                   |     |                   |
                        Hickory-------------|Well suited          |     |Well suited        |
                                              |                   |     |                   |
                        Sylvan--------------|Well suited          |     |Well suited        |
                                              |                   |     |                   |
                        Fayette-------------|Well suited          |     |Well suited        |
                                              |                   |     |