habitats by cuiliqing


									    HABITATS      AT CEDAR CREEK NATURAL                  HISTORY      AREA

    "Habitat" is a casualtenD that I will use for "vegetation type"---I can refer to an old garden
    or the mucky, wet zone at the margin of a peat-filled basin as "habitat". Vegetation types are
    usually understood to follow certain definitions so that areasof land can be mapped or
    describedconsistently. Definitions, or classificationschemes,can focus just on native
    vegetation types or include non-native vegetation. Examples of non-native, disturbed areas
    are old fields, cultivated fields, lawns,wooded pasturesseededto brome grass,and, in our
    area,nutrient-rich marshesthat are dominated by narrow-leavedcattail, hybrid cattail, or
    reed canarygrass. Areas of native vegetation can be classifiedby "natural plant community"
    or "native plant community" schemes. For namesof native plant community types, I have
    used Minnesota's                      A
                      Native Vegetation: KeytoMinnesota's     Natllra/ Communities(1993). This
    Classificationof Minnesota's native vegetation is basedon dominant plants and characteristic
    plants in relation to climate, soils, topography, site history, and disturbanceregime. It does
    not have categoriesfor aquatic communities or disturbed land. It is currently being revised
    basedon a larger analysisvegetation plots in Minnesota in rdation to soil and fire history.

    An important accompanyingreferenceis the Ecological Classification System(ECS) for
    Minnesota, both the maps and descriptions of ecological subsectionsand landtype
                            Native Vegetation the ECS data are availablethrough the
    associations. Minnesota's               and
    Minnesota Department of Natural Resources. Check the Web for current versions and on-
    line access.

    Native habitats gradeinto human-altered,or disturbed habitats. Someremaining examples
    of native habitats have a plant speciescomposition and natural disturbanceregime similar to
    that occurring before the 1850swhen Minnesota becamerapidly settled There are no
    pristine habitats that are historically "accurate" today. Nevertheless,protected natural areas
    acrossthe state and acrossthe globe that are well-documented serveasimportant biological
    benchmarks. Cedar Creek is one of theserare places.

    Native Habitats     at Cedar Creek Natural       History Area


        Maple-Basswood Forest - No typical examplesoccur at Cedar Creek like those
              occurring to the eastin Chisago County (Lindstrom area;St. Croix River Valley),
              in north-central Isanti County on Grantsburg sublobe till (Cambridgearea)or in
              the Rum River bottornlands (Anoka, St. Francis, Cambridge,etc.). Crone's Knoll
              near Cedar Bog Lake is most similar to a maple-basswoodforest. In the 19-s,
              Martha Crone introduced mesic forest wildflowers on her knoll. Some of them
              are not native to Cedar Creek such as bloodroot and snow trillium, probably also
              tall bellwort and large flowered trillium---we will never know for sure.

        Mesic Oak Forest - Relatively rich oak forests at Cedar Creek occur on knolls in the
              Cedar Bog Lake area(Crone'sKnoll, Noms cabin area). The best
              representativeshave sugarmaple, red maple, sharp-lobedhepatica,red oakswith


           typical broad acorns, bark, and branching, and a good variety of forest herbs
           such as canadamayflower, wood anemone,round-lobed hepatica,early meadow
           roe, wild geranium,wild sarsaparilla,mountain rice grass,and Carex  pedunculata.

    Dry Oak Forest - This is the dominant forest type at Cedar Creek. The dominant trees
          are red oak, northern pin oak, or hybrids of the two. American hazelis the
          dominant shrub and chokecherry,juneberry, and tall blackberry are common.
          Pennsylvaniasedgeoccurs throughout and common herbs are bracken fem,
          Canadamayflower, star-flowered false Solomon's seal,wild sarsaparilla, hog
          peanut, wild geranium, and common blueberry.

    Aspen Forest   -   Aspen forest (> 70-80% forest canopy cover) does not occur at Cedar
           Creek although inclusions of big-toothed aspenoccur in dry oak forests.
           Trembling aspenstandshere are classifiedas aspenwoodland.

    Lowland   Hardwood      Forest   -   Lowland hardwoods are common and important ~t
           Cedar Creek but rarely occur here as more than a narrow transition zone or
           ecotone betweenupland forest and wooded swamp. Lowland hardwoods differ
           from hardwood swampsby occurring on mineral soil as opposed to a
           predominandy organic soil. They can also be interpreted as simply the wet-mesic
           expressionof oak forest on the Anoka Sandplain. The canopy treesinclude red
           oak, red oak/Northern pin oak hybrids, white oak, red maple, paper birch, black
           ash, trembling aspen,and white pine. Characteristicshrubs and herbs include are
           common blueberry, bush honeysuckle,blue-beadlily, bunchberry, running
           clubmoss, and round-branched ground-pine. Someinteresting, uncommon
           plants are black huckleberry and early coralroot.


    White Pine Forest - Lackof fire in the 1900s Cedar      Creekallowed  white pinesnorth
          of Cedar Bog Lake to colonize oak forest openingsand old fields---a fairly
          common pattern on the modern landscape. Native white pine forests usually
                                                                           white pine
          originated following large, natural fires. The early successional,
          patchesat Cedar Creek are included in areascalled "white pine-hardwood forest" .
           becausethey lack featuresof the native type.


    Mixed Pine-Hardwood Forest - Native red pine and jack pine at Cedar Creek
          probably occurred as a few, small mixed pine-hardwood standsalong with white
          pine, red oak, northern pin oak and big-toothed aspen. Red pine and jack pine
          north of Cedar Bog Lake are not reproducing and the fonner mixed standsare,
          currendy, extremely small inclusions in white pine-hardwood forest.

    White pine-hardwood Forest - All uplandforests     with white pinein the canopy    at
          Cedar Creek are calledwhite pine-hardwood forests in Cedar Creek Flora 2000
          becausethis reflects the pattern of white pine colonization into existing oak


Oak Woodland/Brush1and          - This is a major habitat type at Cedar Creek, past and
      present Woodland/brushland habitats have varied appearances depending on
      fire history---some are overgrown savannas (up to 800/0canopy and moderate
      density of shrubs) while others are recently burned dry oak forests (as low as
      20% canopy and continuous oak brush at shrub height). Others can devdop
      following outbreaks of oak wilt disease in oak forests.

Aspen Woodland     - Trembling aspen stands at Cedar Creek occur at wetland margins
      and in low-lying areas in savannas and old fidds. They generally have a
      woodland character «80% canopy cover) and are only a few acres or less in size.


Dry Oak Savanna - This was a major upland vegetation type across the Anoka
      Sandplain before European-American settlement and when fires were frequent
      Remaining examples are mostly limited to areas that were too unproductive to
      cultivate or pasture heavily (Sand Dunes State Forest and Clitty Lake Dunes
      (Becker City Park) in Sherburne County, Cedar Creek Natural History Area
      (CCNHA), Allison Savanna Scientific and Natural Area (SNA), and Bunker Hills
      Regional Park in Anoka County. Rice Lake SNA (Sherburne County) and
      CCNHA havesavanna non-dune, outwash soil.

      Dry oak savannas characterizedby widdy spacedbur oak trees and native
      prairie speciesbelow. Characteristicgraminoids are little bluestem,big bluestem,
      Indian grass,porcupine grass,junegrass,and Can-x foenea.Characteristicforbs are
      early buttercup, prairie birdfoot. violet, hoary puccoon, western spiderwort,
      butterfly weed, hoary frostweed, birdfoot coreopsis, leadplant, rigid sunflower,
      prairie sage, rough blazing star and gray goldenrod. Plants found on xeric dune
      crestsand blowouts are false heather, sea-beach     needlegrass,coast jointweed,
      sand            Muhlenberg's sedge,and silky prairie clover.


Dry Sand Prairie - Some areasof dry sandprairie can be mapped asinclusions within
      dry oak savanna but most large prairie openings at Cedar Creek (> 5 acres) appear
      to be areas where savanna trees were removed in the past to create open fidds or
      pastures, thus they are disturbed savannas (examples: prairie with experiment
      "c" Yz mile SE of Lab, prairie 1/4mile south of Fish Lake, old fidd in extreme
      SW comer of section    35).


Mixed Hardwood      Swamp   -   Hardwood swamps at Cedar Creek at mostly a mixture        of
      red maple, paper birch, black ash, red dm, and in a few places, yellow birch.

           They grade into alder swamp, tamarack swamp,white cedar swamp, and lowland
           hardwood forest and do not cover large large areasat Cedar Creek.

    Black Ash Swamp - Black ash swampstend to occur in areaswhere there is
          groundwater seepage.Some small patchesoccur at the periphery of upland
          knolls in the Cedar Bog Lake area. There are even a few skunk cabbageplants
          here, characteristicof seepageareas.


    Minerotrophic Tamarack Swamp - These tamarack swampslack a continuous
          sphagnumcarpet and often grade into alder swampsor rich fens. The diversity
          in these swampsis currendy threatenedby the invasive shrub, glossy-leaved
          buckthorn. An unconunon native shrub, swamp holly, seemsto be in jeopardy.

    SphagnumTamarack Swamp- These tamarack swampshave a "boggy" character,
           that is, they have a continuous, hummocky layer of sphagnummoss.
           Characteristicplants are tawny cotton grass,creeping snowberry, Carexpaupercula,
           and Labrador tea.

    Black Spruce/Tamarack      Swamp   -   The only location of this northern plant
           conununity on the Anoka Sandplainoccurs on sphagnumpeat at the south end
           of Beckman Lake. Herbaceousplant that are also unusual this far south are
           pitcher plant, three-leavedfalse solomon's seal,two speciesof cotton grass
           (Eriophomm                          and
                       pissum,E. chamissonis), Carexlimosa.

    White Cedar Swamp - White cedarswamps         occurprimarilyin the Cedar Bog Lake
          area;a small patch is located near Ice Lake. These swampsare far south of
          similar standsand yet they harbor characteristicplants such as naked bishop's
          cap, small enchanter'snightshade,wintergreen, heardeaf twayblade,and


    Alder Swamp - Alder swampsare dominted by speckledalder (Alm/s incana).There are
           few, if any plants restricted to alder swamps. The herbaceousplants in op~
          are similar to those occurring in rich fens (bluejoint grass,lake sedge,
          those growing in the shadeof alders can also be found in mixed hardwood,
          tamarack,or white cedar swamps.

    Willow Swamp - Willow swampsare not large or distinct at Cedar Creek. They tend to
          occur as inclusions in rich fens or wet meadowsthat have not burned recendy or
          as narrow zones at wedand margins and on wet mineral soil along ditches and
          draingageways. By far, the three most conunon speciesof wedand shrub
          willows here are slenderwillow, Bebb's willow and pussywillow.


Wet Prairie - Wet prairies are nearly completdy lost on the Anoka Sandplainbecauseof
      grazing, draining, woody encroachment,or displacementby reed canarygrassor
      other pasture grasses. I have used this categoryto identify a distinctive little zone
      that is the last vestige of wet prairie on the Anoka Sandplain: wet meadow
      margins---the transitional zone betweenupland prairie and wet meadow
      vegetation. Four State-listedrate plants at Cedar Creek are restricted to this zone
      and a fifth occurs nearby at Carlos Avery WIldlife MangementArea. Wet
      meadow margins with moist, acidic, sandysoil and a history of fire support some
      other rare and unusual plants that are not wet prairie species---grasspink orchid
      and yellow bartonia, for example. The habitat, whatever it is called,is highly
      significant ecologicallyand should be carefully protected.

Wet Meadow - Wet meadows,sedge-dominated,      shallowwedands with little peat
     accumulation, are dominated by bluejoint grassand Hayden's sedgeon the
     Anoka Sandplainand at Cedar Creek.

Poor Fen - Poor fens are peadandscharacterizedby a continuous sphagnummat,
      ericaceousplants, moderatdy low pH, and low nutrient availability. A true bog
      has a lower pH «4.2) and lower nutrient availability. Characteristicplants are
                                         and Carexoligosperma),
      leatherleaf,wiregrass(Carexlasiocapa                      lessercranbeny,
      larger cranberry,balsamwillow, Carexcanescens, Carexchordo1rhiza.

Rich Fen (sedge,shrub, and floating mat subtypes)- Rich fensarepeadands       with near-
      neutral to mildly acidic pH and moderate nutrient availabilty. Rich fens
      commonly occur at Cedar Creek at the edgeof poor fen mats. They also occur
      around open water at Cedar Bog Lake, Beckman Lake, and Ice Lake. Rich fens
      here are often dominated by Carex lacustris, Carex rostrata, or Carex lasiocarpa.
      Shrubby rich fens have abundant bog birch.

Mixed Emergent Marsh - Emergent marshesoccur in open water, flowing water, or
      nutrient-rich water where tall, densesedges,reeds,and cattailsgrow rooted in the
      substrateor as floating vegetation mats. Mixed emergentmarshesoccur at Cedar
      Creek primarily in and around Fish Lake.

Cattail Marsh   - Cattail   marshes (marshes having>   80% cover of Typha spp.) occur at
       Cedar Creek near Fish Lake and in drainageways and ditches. Broad-leaved
       cattail is the natural dominant here. Hybrid cattail and narrow-leavedcattail are
       consideredrecent arrivals on the Anoka Sandplainand in a strict sense,they do
       not form native plant communities.


Lake Beach - At Cedar Creek,a distinctive set of plant speciesoccur on the exposed
      sandyshore of fish Lake, especiallyin low-water years. Few other shallow sand
      lakes on the Anoka Sandplainstill have their native lake beachassemblage.
      Another set of lake beach speciesoccurs on the sand ridge next to the lake that
      formed by ice-heaving.

    River Beach - This habitat at Cedar Creek has been gready altered becausethe creek
           margins and small strandswithin the creek channelare thickly covered by reed
           canarygrass. Native opportunists such as jewelweed,clearweed,small umbrella
           sedges, rushes,and spikerusheshave litde room to colonize the exposedbanks
           after spring flooding becauseof reed canarygrass.


    Aquatic (floating and submerged)- Most aquatic macrophytesthat occur at Cedar
           Creek such aswater lilies, coontail, pondweeds,and duckweedsare angiosperms.
           One macrophyte that occurs in shallow water in Fish Lake is a brisdy erect plant
           a few inches high---like litde piecesof coontail stuck in the sand. This is Char-a,
           an aquaticgreen alga. It is not a vascularplant and therefore isn't in this



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