Vegetation Establishment

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                                Vegetation Establishment

                                5-1      Vegetation Establishment Considerations
                                5-2      Developing a Vegetation Plan
                                5-3      Site Preparation
                                5-4      Establishing Upland Vegetation
                                5-5      Establishing Wetland Vegetation
                                5-6      Selecting Seed Mixes and Plant Materials
                                5-7      Vegetation Plan Implementation
                                5-8      Maintenance for Vegetation Establishment

       T   he Vegetation Establishment Section of the Minnesota Wetland Restoration Guide provides a compre-
           hensive approach to establishing native vegetation in restored and created wetlands and surround-
       ing upland areas. The chapters in this section of the Guide provide detailed information about the steps
       involved in establishing plant communities from developing a vegetation plan to project implementation
       and maintenance.

       The practice of establishing wetland and buffer vegeta-
       tion has evolved as project goals have changed and as
       restoration professionals gain a better understanding of
       how native plant communities work. Many early proj-
       ects focused on restoring hydrology and relying on na-
       tive seedbanks or natural colonization for establishment.
       In recent years, there has been an emphasis on maximiz-
       ing landscape function: creating stable habitat for a wide
       variety of species, providing competition for invasive
       plants by diversifying plant communities, and providing
       benefits for soil and water resources. Expanding project
       goals to include landscape-level functions has led us to
       develop new techniques to manage invasive species,
       plant upland and wetland vegetation, and provide long-                         Figure 5.1
       term care.

                                                                            Figure 5.1
                                                                                         M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E   1

                                                    A primary goal of the Vegetation Establishment Section of the Guide is to
                                                    provide information on current methods to restore vegetation in wet-
                                           lands and surrounding uplands. The information provided is intended to inform
                                           practitioners about their options, so they can achieve project goals and ultimately
                                            advance the field of wetland restoration. The section provides detailed informa-
                                                  tion about a wide range of strategies used in the restoration of upland and
                                                  wetland plant communities.

                                               It is important to keep in mind that every wetland restoration and creation
                                             project is unique. Several different strategies may exist to accomplish the
                                            desired project functions. Project goals, program requirements, personal prefer-
                                          ence, and available funding all need consideration. The recommendations and
                                         project schedules provided for each strategy in this guide should be considered as
                                        a starting point in the planning process and be adapted as needed to meet project
                                       goals and objectives.

    The practice of vegetation establishment is constantly evolving. Input regarding information in this
    section of the Guide will be welcomed; it is intended that the information will be updated as new research
    and practitioner information is obtained.

    Several appendices (Appendix 5, A-K) are provided to support the information in this section of the Guide.
    They include:

    5-A         Invasive Species Control
    5-B         Project Specifications
    5-C         Project Details
    5-D         Design Recommendation for Seed Placement Based on Elevation
    5-E         Developing Custom Seed Mixes
    5-F         Seed Bank Testing Protocol
    5-G         Plant Community Tables
    5-H         Vegetation Establishment Tables
    5-I         Wetland Vegetation Establishment Research Needs
    5-J         Plant Information Website Links
    5-K         Citations

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  5-1 Vegetation Establishment Considerations

                                                                     The following vegetation establishment
                                                                     considerations are included in this chapter:
                                                                     Vegetation Goals
                                                                     Vegetation Establishment Strategies
                                                                        Site Preparation
                                                                        Seeding and Planting

                                                                     Plant Community Restoration
Figure 5.2 Lake Sedge                                                   Wetland Buffers (Uplands)
                                                                        Sedge Meadows, Fresh (Wet) Meadows

T   he establishment of diverse wetland and upland
    plant communities is necessary for a healthy,
functioning wetland ecosystem. To be successful, the
                                                                        and Wet to Wet-Mesic Prairies
                                                                        Shallow Marshes, Deep Marshes and
                                                                        Shallow, Open Water Communities
vegetation establishment process requires a thorough
                                                                        Shrub Swamps and Wooded Swamps
assessment of the project site and a well coordinated
approach, as the project is being planned and imple-                    Peatlands
mented.                                                              Special Site Conditions
                                                                        Wetland Creations
As the vegetation establishment plan is being devel-                    Wetland Enhancements
oped, design staff need to take into consideration site
                                                                        Habitat Considerations
conditions, constraints, site preparation needs, planned
hydrologic conditions, along with desired goals and                  Plant Materials
budget for the project.                                                 Propagule types and sources
                                                                        Seed mix selection and development
The topics covered in this chapter
include information that will influ-
                                                                     Schedule Considerations
ence how the vegetation plan is                                         Timing/Sequencing
developed and implemented. While                                        Weed and Invasive Species Removal
reviewing this information, it is use-                                  Temporary Cover and Soil Stabilization
ful to make notes about topics that                                     Seedbed Preparation
relate to an individual project so that the                             Restoring Hydrology
information can be incorporated into the
                                                                        Planting Dates
vegetation plan.

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    Vegetation Goals
    Every wetland restoration or creation project should
    have unique, well defined goals that will influence the
    scope of the project and the strategies (restoration
    techniques) that will be used to establish vegetation.
    These goals should be defined early in the planning
    of the project and should be consulted throughout
    the restoration process. Typical project goals that can
    influence vegetation establishment needs of a project

        Maximize habitat benefits for wetland/upland wild
        life species
        Improvement of water quality                             Figure 5.4
        Soil and water conservation
        Replacement of lost wetland functions
        Increase diversity of upland/wetland plant species
        Establish plant communities that can compete with
                                                                 Select restoration strategies that will attain project
        invasive species and
                                                                 goals while making efficient use of program or project
        Propagate local sources of plant species.
                                                                 funds that are available. Information in this section of
                                                                 the guide is intended to help designers think through
                                                                 all of the potential strategies that could be used for a
                                                                 project and to select strategies that will work efficiently
                                                                 together. Budgets should be considered through all
                                                                 stages of the project from planning/design, implemen-
                                                                 tation, monitoring, and maintenance.

                                                                 In addition to budget, think about additional resources
                                                                 that could be brought to a project such as additional
                                                                 funding through grants, the use of seed collected from
                                                                 partnering organizations, the trading of restoration
                                                                 services, and the use of donated materials. Minnesota
                                                                 has a long history of partnerships that focus on collabo-
                                                                 ration to strengthen conservation efforts.

    Figure 5.3 Giant Bur-reed

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Vegetation Establishment                                     Specific site preparation strategies are discussed and
Strategies                                                   included in Section 5-3 - Site Preparation. Those strate-
                                                             gies include clearing and grubbing, sediment removal,
Strategies refer to individual restoration techniques        crop production, perennial vegetation removal, tilling
that can be applied to a project; examples include her-      for weed control, seedbed preparation, and the use of
bicide application, drill seeding, and mowing. Strategies    temporary cover crops.
chosen for site preparation, planting, and maintenance
will define how work will be conducted at a project
site. Plan all phases of a project to work together and
ultimately meet project goals. An overview of the more
general vegetation establishment stages follows, with
more specific and detailed strategy discussions occur-
ring in the site preparation, planting, and maintenance
chapters that follow.

Site Preparation                                             Planting
The success of many projects can be attributed to the        Planting strategies include the consideration and selec-
effort and methods used to prepare a site for planting.      tion of seed mixes and plant materials along with the
Proper site preparation is essential. The strategies for     various methods available to plant and stabilize a proj-
site preparation involve methods to eliminate undesir-       ect site. Planting strategies are included in the Guide
                                                             for both uplands and wetland areas. Successful wetland
                                                             restoration and creation projects consider all available
                                                             strategies for establishing vegetationand manage the
                                                             implementation of those strategies with respect to
                                                             the goals and objectives of the project as well as the
                                                             implementation timeframe. This includes coordination
                                                             with any on-site construction activities that are planned
                                                             along with the expected timing of hydrology being
                                                             restored or provided to the site.

                                                             Section 5-4, Establishing Upland Vegetation includes
                                                             specific strategies for establishing vegetation on upland
                                                             areas including; broadcast seeding, seed drills, upland
                                                             containerized plants and rootstock, upland trees and
Figure 5.5 Tilling, Photo by Prairie Restorations, Inc.      shrubs, bacterial and mycorrhizal inoculums, and up-
                                                             land stabilization methods.
able plants and prepare the site soils for planting. Inva-
sive species can be a significant impediment to the es-      Section 5-5, Establishing Wetland Vegetation
tablishment. Strategies to remove or control them take       includes specific strategies for establishing vegetation
careful consideration. Reed canary grass, in particular,     in wetland areas including; utilizing remnant native
has been a significant hurdle for many projects in Min-      seedbanks, broadcast seeding wetlands, hydroseeding
nesota. It it is a component of many wetlands in the         wetlands, wetland containerized plants and rootstock,
state and once established it is very difficult to remove.   wetland trees and shrubs, peatland restoration, and
When invasive species are present in a wetland, deci-        wetland stabilization methods.
sions need to be made as to whether the project can be
successful. If they cannot practicably be removed or can     Section 5-6, Selecting Seed and Plant Materials
easily re-enter a site after their removal, the feasibil-    includes discussion on the development of seed mixes
ity of the project and its goals need to be reassessed.      and the selection of seed and plant materials for a

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                                                                   to long-term maintenance schedules provides direc-
                                                                   tion, establishes budgeting needs for projects, and en-
                                                                   sures that project goals will continue to be met. Long
                                                                   term strategies for maintenance and management of
                                                                   both upland and wetland vegetation is discussed in
                                                                   Section 6 – Project Monitoring, Maintenance and
                                                                   Management. Appendix 5-A provides specific guid-
                                                                   ance and management schedules for invasive species
                                                                   common to restored wetlands. The information for
                                                                   individual species can be useful in the development of
                                                                   maintenance schedules.

                                                                   Plant Community Restoration
    Figure 5.6 Planting Containerized Plants                       The identification of historic wetland types and associ-
                                                                   ated plant communities, along with some understand-
    Monitoring and Maintenance                                     ing of the extent that these areas can be hydrologically
                                                                   restored, should have some influence on the plant
    Frequent site visits to monitor the establishment of           communities that should be planned for a site. The
    vegetation are essential to controlling the establish-         plant communities that previously existed at a site
    ment of weeds and invasive species. The most success-          should be the goal for most restoration projects, as
    ful projects tend to have well-timed monitoring and            the on-site soils, hydrology, and other environmental
    rapid treatment of invasive species.                           conditions will be best suited to support the establish-
                                                                   ment of these same historic communities. There are
    Controlling weeds is essential to the success of any           cases where existing and restorable conditions are no
    project, particularly during the first three to five years     longer conducive to the historic community due to
    after vegetation establishment as desired plant species        changes in soils, hydrology, or surrounding landuse.
    are beginning to germinate and develop. It is impor-           Other communities that are better adapted to these
    tant for every project that vegetation maintenance is          modifications should be considered .
    planned and that funding is set aside or made available
    for this work. Specific short                                  During the site assessment and evaluation phase of
    term maintenance strategies                                    the project, a concept plan of some type should have
    are discussed and included in                                  been developed that identified locations and types
    Section 5-8, Maintenance for                                   of preliminary plant communities for the site. As the
    Vegetation Establishment.                                      actual vegetation plan is now ready for development,
    Those strategies include                                       the type and location of plant communities should be
    herbivore control, mowing                                      refined with respect to the site’s goals, limitations and
    for establishment, herbicide                                   available funding. Figure 5.8 shows common plant
    application for establish-                                     communities that are found in Minnesota’s landscapes
    ment, biological control,                                      and are used as a guide for developing a project’s
    hand weeding, watering, and                                    vegetation plan. The plant community types that are
    hydrology control for vegeta- Figure 5.7                       referred to in this Guide follow Wetland Plants and
    tion establishment.                                            Plant Communities of Minnesota and Wisconsin (Egg-
                                                                   ers and Reed 1997).
    Restoration projects should be planned to sustain the
    restored community into the future. Problematic plants
    in the watershed may influence future maintenance
    needs. Weeds will always be a threat to the restoration
    site, particularly if there is a disturbance that allows for
    their establishment. The development and adherence

6   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                    M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
  Wetland Plant Communities
  Upland              Sedge Meadow                           Shallow Marsh          Deep Marsh                 Shallow, Open Water
  Prairie             Fresh (Wet) Meadow
                      Wet Prairie
                      Shrub Swamp

                      (Communities with similar
                      hydrology but differences in
                      species dominance)

1.5 feet above
pool elevation

                  Capilary fringe .5 feet
                                            Pool Elevation
                  above pool elevation
                  in sand

Figure 5.8

Wetland Buffers (Uplands)
                                                                  Site evaluation information that is important to consid-
The buffer around a wetland provides upland nesting               er in the design of buffers includes soils, slope, existing
and brood cover for wildlife species as well as protects          vegetation, historic vegetation, and surrounding land
the biological integrity of restored wetlands. As a general       uses. As with wetlands, the historic community that ex-
rule, wetland buffers should be made as large as possible         isted at a site is commonly the goal for the restoration
to increase use by species that require large areas for           of upland buffers. Forested communities can some-
successful nesting and to decrease predation. Promoting           times be more expensive to re-establish than prairie
buffering within the watershed will improve water qual-           but new advances have been made in the establish-
ity and minimize the influence from invasive species.             ment of forests through the direct seeding of tree and
                                                                  shrub seeds. The restoration of upland prairie commu-
                                                                  nities is receiving increased attention due to their value
                                                                  for biofuel production, along with the well documented
                                                                  benefits of soil and water conservation, plant diversity,
                                                                  and habitat restoration. Recent research has demon-
                                                                  strated the importance of soil fungi, prescribed fire,
                                                                  and grazing on prairie diversity. Strategies are presented
                                                                  in this guide for both forest and prairie establishment

Figure 5.9

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    Sedge Meadows, Fresh (Wet) Meadows and
    Wet to Wet-Mesic Prairies
    Sedge meadows, fresh (wet) meadows, and wet to wet-
    mesic prairies will have saturation within one foot of
    the surface and tend to transition upslope into upland
    plant communities. Site evaluation information that
    is important to consider during the planning of these
    communities include soils, hydrology, existing vegeta-
    tion, historic vegetation, potential seedbank, and influ-
    ences from surrounding landuses. Remnant seed banks
    can sometimes be relied upon for some species in
    these communities but many sedge meadow species,
    especially sedges that do not establish well from rem-
    nant seed, will require additional seeding to provide a
    diverse mix of vegetation types.
                                                                   Figure 5.11 Shallow Marsh

                                                                   Site evaluation information that is important to
                                                                   consider during the planning of these communities
                                                                   include soils, hydrology, existing vegetation, historic
                                                                   vegetation, potential seedbank, and influences from
                                                                   surrounding landuses. Natural dispersal and seedbanks
                                                                   can often be relied on to establish shallow and deep
                                                                   marsh species. Additional seeding is often necessary if
                                                                   repeated disturbance or sediment accumulation has in-
                                                                   fluenced the native seedbank. Fluctuating water levels
                                                                   and wave action can make it difficult to establish seed
                                                                   in shallow marsh zones, so it is common to plant live
                                                                   plants along the edge of the water and let them spread
    Figure 5.10 Wet Meadow                                         into deeper water. Narrow-leaf and hybrid cattails are
                                                                   a significant threat to marsh communities and often
    These communities are prone to the invasion by reed            require management to allow other emergent vegeta-
    canary grass and other undesirable species. As a result,       tion to establish and persist.
    there should be careful selection of site preparation
    strategies to remove any unwanted plant species and to
    establish more desirable species that will create competi-
    tion into the future. Long-term maintenance is required;
    reed canary grass is a threat even to restoration sites that
    have been established with diverse vegetation.

    Shallow Marshes, Deep Marshes and Shallow,
    Open Water Communities
    Shallow marshes, deep marshes, and open water com-
    munities occur in areas with permanent to seasonal             Shrub Swamps and Wooded Swamps
    shallow water. The dominant vegetation type is emer-           Wooded swamps have mature trees with diameter at
    gent aquatic plants in shallow marshes with a transition       breast height of six inches or greater, more than 17
    to floating-leaved and submergent plants with increas-         trees per acre, and more than 50 percent canopy cover.
    ing water depths.                                              Shrub swamps lack mature trees and have a dominance
                                                                   of woody deciduous shrubs.
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                                                           vegetation, historic vegetation, nearby donor sites, and
                                                           influences from surrounding landuses such as nutrients
                                                           that may promote weed growth. During peatland res-
                                                           toration, an existing area of bog commonly is used as a
                                                           borrow site for collecting Sphagnum moss to be spread
                                                           on the restoration area (Quinty and Hood 1998). The
                                                           mulching of re-introduced plant fragmentscan also be
                                                           an important part of the restoration process. The plant-
                                                           ing of shrubs or other perennial species can also aid in
                                                           the establishment of Sphagnum by providing shade and
Figure 5.12 Shrub Wetland                                  protection from wind (Bourdreau and Rochefort 1998).

Site evaluation information that should be considered      Special Site Conditions
during the planning of shrub and forested wetland
communities include soils, hydrology, existing vegeta-     Wetland Creations
tion, historic vegetation, potential seedbank, potential
                                                           Wetlands that are created through excavation have
regeneration from nearby trees and shrubs, and influ-
                                                           unique challenges related to the establishment of na-
ences from surrounding land-uses. The ground-layer,
                                                           tive vegetation. In most cases, excavated wetlands do
shrub layer, and canopy layer should receive equal
                                                           not promote the rapid growth of vegetation since soils
consideration during the planning process. Establishing
                                                           tend to be nutrient poor and lack wetland seedbanks.
forested wetlands is a long-term process and requires
                                                           Soils that will provide the best growing conditions
careful consideration of maintenance and herbivore
                                                           for plants have a substrate for rooting, nutrients, and
control strategies. See Section 5-6, Wetland Planting,
                                                           sufficient aeration. It is common to add topsoil over
Wetland Trees and Shrubs for additional information.
                                                           excavated wetlands to improve conditions for plant
                                                           establishment and growth. However, adding soils rich
Peatlands                                                  in nutrients may aid the establishment of reed canary
                                                           grass and cattails. The soils found in nearby natural
                                                           wetlands mayprovide clues that help guide decision
                                                           making related to the use of topsoil at a site.

                                                           Donor soil from existing wetlands may be used as a
                                                           substrate for created wetlands. It is crucial that topsoil
                                                           or donor soils do not contain seeds of invasive species.
                                                           In some cases, donor soils are a source of desirable
                                                           seed and propagules of native species and will aid the
                                                           establishment of the wetland. Piles of topsoil that will
                                                           be used for a wetland should be kept small to minimize
Figure 5.13
                                                           loss of soil organisms. Placing topsoil in rows is often
                                                           an effective strategy. Topsoil should be spread as soon
Peatlands include open bogs and coniferous bogs.           as site conditions allow. Soil compaction after topsoil
Peatlands have water-saturated soils that are composed     grading should be avoided; soil should be loosened
of partly decayed remains of plants. The plant material    with rippers when compaction occurs. The site prepara-
accumulates as a result of slowed bacteria and fungal      tion, planting, and maintenance strategies discussed in
action in the waterlogged environment. Peatlands are       this section of the Guide will apply to wetland creation
found primarily in the boreal forest biomes, which have    sites as well as traditional wetland restorations.
cool temperatures and short summers. Site evalua-
tion information that should be considered during the
planning of shrub and forested wetland communities
include thickness of existing peat, hydrology, existing

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     Wetland Enhancements                                          Habitat Considerations
                                                                   The creation of wildlife habitat is a popular goal of wet-
                                                                   land restoration projects. Wildlife species from inverte-
                                                                   brates to waterfowl require diverse plantings to provide
                                                                   food sources throughout the year.

                                                                   It may be possible to connect to high quality habitats or
                                                                   environmental corridors that exist near the project area.
                                                                   Environmental corridors are areas of natural vegetation
                                                                   that can act as passageways between isolated habitats.
                                                                   One example is a tree-lined stream corridor that con-
                                                                   nects two wetlands that are otherwise separated by a
                                                                   developed area. Another example is a field row of tall
                                                                   herbaceous vegetation, shrubs, or trees that provide
                                                                   cover for wildlife. If such areas exist nearby, connecting
                                                                   wetland’s buffer to them willincrease the usefulness of
                                                                   the wetland for wildlife species.

                                                                   Existing wetlands that connect to a restored or created
                                                                   wetland can act as a source of desirable native seed or
                                                                   of undesirable invasives. Floating wetland seeds and
                                                                   plants can be transported from one wetland to another
     Figure 5.14                                                   during high water events.
     The enhancement of existing wetlands involves the
     removal of invasive species or establishment of native
     species to increase plant diversity. The restoration strat-
     egies proposed in this section of the Guide can also be
     used for the enhancement of existing wetlands.

                                                                   Figure 5.16

                                                                   Plant Materials

                                                                   Propagule Types and Sources
                                                                   The availability of existing native seedbank, seeds, and
                                                                   plants can influence the strategies that are chosen for
                                                                   a site. If native seedbank is present, it can be a source
                                                                   of “local” seed. Marsh communities can be difficult to
                                                                   establish from seed alone and are often planted with
     Figure 5.16                                                   containerized plants, pre-vegetated mats, transplanted
                                                                   materia,l or bare-root plants.

10   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                   M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
                               There may be some               activities. Contractors that are conducting construction
                               areas of the state where        activities and those focusing on vegetation establish-
                               local seed and other            ment should be aware of each other’s schedules to
                               plant materials can-            ensure that each phase of the project will be conducted
                               not be found. Seed              at the correct time. Detailed timelines are very useful to
                               that is moved from the          keep all phases of a project working together.
                               southern part of the
                               state to the northern
                               part may result in plants
Figure 5.17                    that do not produce
                               viable seed. It is encour-
aged that project partners work together to find local
sources of plant materials.

Seed Mix Selection and Development
Project budget often has a significant influence on the
seed mixes selected for a site. Species diversity is a goal,
but increased diversity commonly involves higher seed
costs. Diverse seed mixes tend to result in more stable
plant communities that fill available niches and prevent
invasion by undesirable species. Seed mixes should
be selected to match hydrologic conditions at a site
and have a combination of early and later successional
                                                               Figure 5.18 Canada Thistle
species to ensure that the planting will persist and
regenerate.                                                    Weed and Invasive Species Removal
There are many seed mixes used in the state ranging            The removal of undesirable weeds such as reed canary
from mixes based on NRCS Practice Standards, private           grass, Canada thistle, and wild parsnip often takes
vendor mixes and State seed mixes. Ultimately, seed            more than one year to complete. This is especially
mixes should be chosen that fit project goals. In some         true with reed canary grass, as this species is a prolific
cases, custom seed mixes are developed for sites. This         seed producer and tends to have extensive rhizomes.
can be a good strategy to match species to specific site       Reed canary grass is commonly sprayed in the fall and
conditions and to replicate historic plant communities.        then treated through the next year to obtain sufficient
See Section 5-6 Selecting Seed and Plant Materials for         control before planting in the fall or following spring.
more information on the use and selection of seed and          Species such as reed canary grass, Canada thistle, and
plant species.                                                 wild parsnip must be thoroughly controlled at a site
                                                               before seeding is conducted. Additional discussion on
                                                               strategies for weed and invasive species removal occurs
Schedule Considerations                                        in Section 5-3 - Site Preparation.

The timing of restoration strategies is often essential to
project success. Individual phases of a project should
be summarized in project schedules so that contractors
can understand when various phases of work should
be conducted. Activities related to vegetation estab-
lishment should be timed appropriately with seasonal
conditions and coordinated with planned construction

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                                                                   Restoring Hydrology
                                                                   The timing of hydrology restoration is important for the
                                                                   success of new wetland plantings. The ideal situation
                                                                   is to restore hydrology slowly as vegetation increases
                                                                   in height to minimize the risk of drowning new plant-
                                                                   ings. On sites that do not have water control structures,
                                                                   it is common to plant after the hydrology is restored
                                                                   to a relatively stable state, but this limits the types
                                                                   of equipment that can be used on saturated soils. If
                                                                   possible, the seedbed can be prepared the previous
                                                                   fall and seeding can be conducted if conditions the
                                                                   following spring will not cause the seed to float or be
                                                                   washed away. Seed will germinate the following spring
                                                                   or as hydrologic conditions are favorable for individual
                                                                   species. In some cases, it may be beneficial to wait until
     Figure 5.19 Slough Grass                                      water levels of wetland pools stabilize in the spring to
                                                                   plant emergent species as seed or containerized plants
                                                                   to protect seedings.
     Temporary Cover and Soil Stabilization
                                                                   Coordinate the planning and design of wetland veg-
     Stabilizing the site as part of the vegetation estab-
                                                                   etation plans with the engineers and others involved
     lishment process can be critical to the success of the
                                                                   in the planning and design of construction plans to
     project. For example, most wetland seeds will not
                                                                   ensure that everyone is aware of the needs and issues
     germinate if covered by more than 0.25 inches of soil.
                                                                   associated with restoring hydrology to the site. The
     Therefore, it is important the site be stabilized after any
                                                                   management of hydrology as vegetation is establishing
     construction or site preparation activities to limit the
                                                                   is covered under Section 5-8, Maintenance for Vegeta-
     movement of on-site sediment and protect the invest-
                                                                   tion Establishment.
     ment and effort put forth in seeding and planting the
     site. The use of temporary cover crops, mulching, or
     establishing upland buffers before seeding or planting        Planting Dates
     wetland vegetation are all recommended stabilization          Generally, spring seeding is conducted before July 1st
     strategies to consider that can improve the success of        in the northern half of the state and before June 15th
     wetland seedings and plantings.                               in the southern half of the state; dormant fall seeding
                                                                   is conducted after October 15th in the northern half of
     Seedbed Preparation                                           the state and after November 1st in the southern half
                                                                   of the state, and before freeze-up of the upper soil sur-
     The preparation of the seedbed should only occur
                                                                   face. It is common to plant wetland species and upland
     after invasive species and weeds are controlled to the
                                                                   mixes with a dominance of forbs in the fall to allow for
     extent desired and possible. Seedbed preparation
                                                                   stratification of seed over winter. Strategies are also pre-
     techniques can vary significantly from seeding shortly
                                                                   sented in the guide for seeding during winter months.
     after soybean harvest to combinations of disking, har-
                                                                   Wetland seed can be planted in the spring but many
     rowing, and cultipacking. The ultimate goal of seedbed
                                                                   species may not germinate until the following spring
     preparation is to provide ideal growing conditions for
                                                                   unless pre-stratified. The planting of bare-root plants is
     the species being planted. Additional discussion on
                                                                   conducted as early in the spring as possible when soils
     site preparation strategies occurs in Section 5-3 - Site
                                                                   are moist. This is also a good practice for containerized
                                                                   plants. Trees and shrubs can be planted successfully in
                                                                   the fall until freeze-up.

12   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                   M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E

  5-2 Developing a Vegetation Plan

                                                                      The steps involved in developing a vegetation
                                                                      plan include the following:

                                                                         Information Review
                                                                         Writing a Project Overview
                                                                         Developing the Planting Zone Map
                                                                         Selecting Restoration Strategies
                                                                         Writing Specifications and Notes
                                                                         Selecting Project Details
                                                                         Developing Project Schedules
Figure 5.20

T   he successful establishment of vegetation is an
    important and rewarding component of a wetland
restoration or creation project. Before any planting
work begins, a significant amount of planning and
design work is needed. For a project to be successful,
the design needs to provide sufficient detail for the
contractor and others involved in the vegetation estab-
lishment effort. This occurs through the preparation of
plans, specifications, and other contract documents.
The clearer, more comprehensive, and detailed the
vegetation plan documents, the greater the likelihood
for project success.

This chapter focuses on the process of developing a
vegetation plan and how to implement the plan to
achieve the intended project goals and objectives.
Plan development is discussed early in this section of
the Guide as understanding of the content of a well-
developed vegetation plan will serve as a foundation
as the detailed vegetation establishment strategies are
discussed in later chapters.

This chapter presents a comprehensive process for
developing a vegetation plan using examples and tem-
plates. As this Guide is intended to be useful for a wide
variety of project types with varying goals and budgets,         Figure 5.21 Cup Plant
the discussion of plan development allows designers
to select steps and to utilize a level of detail that fits
individual project needs.

DECEMBER 2008                                                                           5  2 D E V E L O P I N G A V E G E TAT I O N P L A N   13
     The appearance of vegetation establishment plans             and having the accompanying written portion of the
     varies depending on project scope and ultimate goals         plan include a project overview, written description/
     for project vegetation. For example, a plan may be very      specifications of strategies for site preparation, planting
     detailed for a mitigation project and less detailed for a    and maintenance, along with details and project schedules.
     conservation planting. It is up to the project designer      (Link to Appendix I, Vegetation Plan Examples)
     to determine the level of detail and what steps will be
     used to develop a plan for an individual project. The        A template for the written portion of a plan is presented
     more involved the designer or project manager are in         below. Plan components can be inserted as they are
     the actual on-site implementation activities, the less       comjpleted, with more or less detail depending on proj-
     detailed the plan may need to be.                            ect scope. Even the simplest project should have basic
                                                                  informaiton for each of these components.
     Nonetheless, all vegetation establishment plans need
     to consider the type(s) of establishment strategies that
     will be used. There will need to be a planting map of          Table 5.1 Vegetation Plan Template
     some sort along with instructions for site preparation,
     planting, and maintenance. To support those instruc-           Project Name
     tions and to ensure they are properly implemented,             Date:
     notes and specifications need to be prepared that provide
     the specific requirements for implementation.                  A. Project Overview:

     Vegetation plans can take many forms depending on              B. Project Administration
     the type of project and designer preference. Most plans,         Bidding and Contractor Selection Specifications:
     however, should consist of both written and graphical
                                                                      Permits and Certification Requirement Specifications:
     information that will guide all work related to establish-
     ing vegetation at a project site. The graphical portion of       Measurement and Payment Specifications:
     the plan is usually represented on what is often called
     the planting zone map. The written portion of the plan         C. Site Preparation
     will provide detailed information about how the work             Site Preparation Description/Specifications:
     will be conducted and will describe all restoration              Site Preparation Schedule:
     strategies to be used as well as accompanying specifi-
     cations, notes, details, and project schedules.                D. Planting
                                                                      Planting Description/Specifications:
                                                                      Planting Details:
                                                                      Planting Schedule:

                                                                    E. Plant Materials
                                                                       List of Seed Mixes and Other Plant Materials:
                                                                       Seed and Plant Specifications:

                                                                    F. Site Maintenance
                                                                       Maintenance Description/Specifications:
                                                                       Maintenance Schedule:

     Figure 5.22 Green Bulrush                                      G. Project Implementation Schedule:
                                                                      Implementation Schedule:
     The process to develop a vegetation plan as proposed
     in this Guide involves preparing a comprehensive plant-        Note: see accompanying planting zone map
     ing zone map that includes important project notes

14   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                  M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
Information Review                                          Table 5.2 Use of Site Information in
                                                            Development of the Vegetation Plan

                                                                                       Importance for Vegetation
                                                                                       Plan Development

                                                                                       Site contours will help determine
                                                                                       the location of planting zones,
                                                            Site topography
                                                                                       seed mixes, and other planting
                                                                                       strategies at the site.

                                                                                       Aids in the determination and
                                                            Geology and soils
                                                                                       location of historic wetland

Figure 5.23 Establishing Emergent Plants                                               Helps determine possible threats
                                                                                       to the site such as invasive species,
                                                            Land use information
Prior to developing the vegetation plan, conduct a                                     nutrients, and changing water
                                                            from aerial photo-
                                                                                       levels. May influence the resto-
thorough review of the information collected during         graphs and site visits
                                                                                       ration site and the selection of
the Site Assessment and Evaluation phase of the proj-                                  restoration strategies.
ect. The collection and evaluation of this information is
discussed in Section III of the Guide.                                                 Look for evidence of sedimenta-
                                                                                       tion of wetland basins or other
The information collected as part of the site assess-                                  erosion problems, as well as the
                                                            Previous land use
                                                                                       introduction of aggressive species
ment and evaluation is important in the development                                    as well as fertilizer, herbicide and
of a concept plan and will continue to be important                                    pesticide use..
through all stages of a project including vegetation
plan development, implementation, and maintenance.                                     Helps to select plant communities
The following table summarizes the information that         Historic vegetation        and species appropriate for the
should have been collected during the site assessment                                  site.
and shows how that information relates to the develop-
ment of the vegetation plan.                                                           A threat or a benefit, the presence
                                                            Existing Seedbank          of an existing may influence the
                                                            potential                  planting strategies, seed mixes,
                                                                                       and control efforts.

                                                                                       Aerial and ground-level images
                                                                                       can be a good reference during
                                                            Site photography           the vegetation plan development.
                                                                                       Also useful for tracking restoration

                                                                                       May Influence the planning of site
                                                            Existing native
                                                                                       preparation, planting, and mainte-
                                                                                       nance strategies.

                                                                                       May influence the planning of site
                                                            Existing invasive
                                                                                       preparation, planting, and mainte-
                                                                                       nance strategies.

                                                                                       Wetlands in surrounding areas
                                                                                       may aid selecting restoration
                                                            Reference wetlands
                                                                                       strategies and vegetative

DECEMBER 2008                                                                     5  2 D E V E L O P I N G A V E G E TAT I O N P L A N   15
                                                                  nance strategies. Information about the extent of wet-
                                                                  land buffers and connection to habitat corridors will aid
                                                                  in decision-making about upland planting strategies.

                                                                  One final piece of information to review in preparation
                                                                  for developing the vegetation plan is the Vegetation
                                                                  Establishment Considerations that were discussed in
                                                                  Chapter 1. Notes that were taken during the review of
                                                                  establishment considerations should be reviewed and
                                                                  considered during the development of the vegetation plan.

                                                                  Writing a Project Overview
                                                                  As part of developing the vegetation plan, it may be
                                                                  helpful to write a brief summary about the restoration
                                                                  project including the vegetation goals for the project
                                                                  and how restoration will be conducted. The overview
                                                                  can act as a reference as the plan is developed to en-
                                                                  sure that the whole document is working in a way that
                                                                  meets the overall goals for a project. The overview can
                                                                  also be used for project promotion or to educate the
                                                                  public about the project.

     Figure 5.24 Marsh Milkweed

     The development of a concept plan is discussed in
     Section III of the Guide as part of the Site Evaluation
     Chapter. If a concept plan was developed for a project,
     it should be reviewed and revised as necessary to meet
     the current needs of the project. The information in the
     concept plan should be used to guide the development
     of the detailed vegetation plan. Generally, the concept
     plan will have included the following information as it
     relates to establishment of site vegetation:

         Areas of Invasive Species to Control
         Areas of Native Vegetation to Protect
         Connection to Habitat Corridors
         Existing and Desired Extent of the Wetland Buffer
         Type and Locations of Plant Communities to
         be Restored

     The type and location of plant communities to be
     restored will guide the selection of restoration strate-
     gies and plant species for the site. Information about
     invasive species and native vegetation will inform the
     selection of site preparation, planting, and mainte-
                                                                  Figure 5.25 Sawtooth Sunflower

16   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                  M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
Figure 5.26 Sample Planting Zone Map

Developing the Planting Zone Map
                                                            Depending on complexity or scope of the project, it
The planting zone map is a graphical portrayal of the       may be beneficial to utilize the site topographic map
vegetative plant communities that are planned for a         as the base for preparing the planting zone map. The
site. Information that should be included on a plant-       creation of different planting zones is often elevation-
ing zone map includes existing features such as trees,      based. The detailed topographic map provides a nice
remnant plant communities, property/easement lines,         platform to depict the location for specific plantings.
roads/access and drainage ditches, as well as planned       Projects with simple vegetative plans can easily be
features such as location of seed mixes, other plant        portrayed on an aerial photo or sketch of the site. Incor-
material to be used at the site, and any erosion control    porated within or attached to the planting zone map
measures that will be required. The location of different   should be a seeding/planting table that summarizes
seed mixes can best be represented by using different       seed mixes to be used, areas and amounts for each seed
hatching patterns on the map. The locations of tree         mix, seeding rates and methods, lists of species in seed
plantings, containerized plants, and other types of         mixes, species to be planted as containerized plant and
plant material are often represented by symbols on the      rootstock, the number of plants needed for the project,
map. A key or legend summarizes the meaning of hatch        and the type of plant material that will be supplied (i.e.,
patterns and symbols.                                       seed, potted plants, cuttings, and rootstock).

DECEMBER 2008                                                                    5  2 D E V E L O P I N G A V E G E TAT I O N P L A N   17
         Table 5.3 Example seeding/planting table
         Planting Zone                     Area Planted           Seed/Plant Mix         Seeding/Planting                 Seed/Plant Rate
                                           (Acres)                                       Method                           (PLS seeds/sf)

         1                                 2.26                   BWSR Mix W1            Broadcast                        166

         2                                 3.47                   BWSR Mix W2            Broadcast                        200

         3                                 9.45                   BWSR Mix U5            Drill                            60

     It is also common to include key notes about a project                 Writing Specifications and Notes
     on the planting zone map depending on the scope of
     the project and space available on the plan.                           Project specifications and notes provide specific writ-
                                                                            ten direction to contractors and field crews on how
     Computer programs such as AutoCAD and ArcMap are                       individual strategies should be conducted. They help
     useful for drawing the boundaries between planting                     ensure that the goals of the project designer are clearly
     zones and can be used to calculate planting areas to aid               communicated to implementation crews.
     in the determination of plant material needs.
                                                                            Specifications are commonly incorporated into the writ-
     In some cases, complex project sites need to be sepa-                  ten portion of the project in a paragraph format. They
     rated into different units. Each unit may have separate                can also be written directly on the planting zone map
     seeding zones. Below is an example of a planting zone                  or compiled as a separate document, depending on the
     map with separate units.                                               number of specifications included for a project.

                                                                            Project specifications for all phases of a project are
     Selection of Restoration Strategies                                    included in Appendix V-B for bidding and contractor
                                                                            qualifications, equipment needs, site preparation strate-
     As part of preparing a vegetation establishment plan,
                                                                            gies, planting strategies, maintenance strategies, layout,
     the entire vegetation establishment process needs to
                                                                            and staking. It is recommended that project designers
     be considered to determine how best to achieve suc-
                                                                            will select specifications that best fit the specific needs
     cess and meet project goals. All strategies must work
                                                                            of their project and adapt specifications as needed for
     together, taking into consideration effectiveness and
                                                                            their project. Additional specifications may need to be
     costs. Chapters to follow introduce the most common
                                                                            written to fit specific site conditions and project needs.
     strategies used to restore wetland vegetation. Dis-
     cussions of individual strategies within the chapters
     include an overview of the strategy as well as informa-
     tion about equipment and materials, typical strategies,
     influence on other strategies, resources, links to speci-
     fications, and details. All of this information is intended
     to aid in the development of the vegetation plan and
     result in a successful implementation process. As res-
     toration strategies are chosen for a site, related project
     specifications, notes, and details should be inserted
     into the plan.

18   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                             M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
Figure 5.27 Installing emergent plants

Contract specifications should be clearly written and      The graphical information on the planting zone map
detailed benchmarks should be incorporated into            often needs written information to accompany it to
specifications. The following key areas can pose prob-     clearly state what is required and how it is to be accom-
lems and should have clear specificatons to prevent        plished. This information can be provided in the form of
problems during the restoration process:                   notes. Notes are key specifications that contractors ab-
                                                           solutely need to know about a project. The information
  Compliance with specified seed mixtures                  in notes is often repeated in the written portion of the
  (species mix, purity, seed source & germination rates)   plan. It is important that project notes and specifica-
  Delays due to inclement weather                          tions do not have conflicting information. Project notes
                                                           tend to focus on the following topics:
  What constitutes acceptable seed bed preparation
  Compliance with weed control specifications
                                                             Project timing and sequencing
  Overall warranty of the contractor’s work
                                                             Site features to protect
                                                             Sediment and invasive species control considerations
                                                             Restoration strategies that have a high degree
                                                             of complexity
                                                             Propagule handling

DECEMBER 2008                                                                  5  2 D E V E L O P I N G A V E G E TAT I O N P L A N   19
     Figure 5.28 Sample project detail from the Minnesota Department of Transportation

     Selecting Project Details                                    the activity. The process of developing schedules will
                                                                  aid in the understanding of how site preparation, plant-
     Details are diagrams/illustrations that show how site        ing, and maintenance strategies will work together.
     features are to be constructed or installed. Common          In some cases, site preparation and planting schedules
     details related to planting include tree and shrub           are combined; as these are often a continuous process.
     planting, wave break structures, and herbivore control
     techniques. When used, project details are commonly          The maintenance schedule for vegetation establish-
     located on a separate plan sheet or in the written por-      ment summarizes the timing of maintenance activities
     tion of the plan. Appendix V-C includes project details      for a project site during the first three to five years. It is
     that can be incorporated into the vegetation plan.           common to show site monitoring visits on the mainte-
                                                                  nance schedule as these activities are often combined.
     Developing Project Schedules                                 In other cases, separate monitoring schedules will be
                                                                  developed for a site. Chapter 7 provides additional
     Project schedules include site preparation, planting,        discussion on Maintenance for Vegetation Establish-
     and maintenance schedules. Schedules are generally in-       ment whereas discussions of project monitoring and
     cluded in the written portion of the plan and may also       long-term maintenance are included in Section 6.
     be included on the planting zone map.

     Project schedules should summarize timetables for spe-
     cific restoration strategies that will be conducted and
     show the projected date for and a description of

20   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                   M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
  Table 5.4 Sample Site Preparation and Planting Schedule

            September                          Harvest Crops

                                               Spot Treat Problematic Perennial
                                               Weeds such as Canada thistle

            September/Early October            Conduct Seedbed Preparation

                                               Spot Treat Problematic Perennial
            Early October

            October 15 - freeze-up             Conduct Dormant Seeding
                                                                                           Figure 5.29 Blue Vervain

  Table 5.5 Sample Maintenance Schedule

                     Mow uplands to 6-8 inches approximately every 30 days after planting until September 30th. Mow-
                     ing frequency should depend on weed height, with a goal of mowing as weeds reach 12 inches. Mow
   2010              wetlands to 6-8 inches approximately every 30 days if equipment will not cause soil disturbance. Moni-
                     tor monthly for weed and erosion problems. Spot treat Reed Canary Grass, Canada thistle and other
                     problem species in wetlands and uplands as needed.

                     Mow to 6-8 inches twice, one time around June 15th and once around July 30th, before weeds set seed.
                     Mow in plands and wetlnad areas if equipment will not cause soil disturbance. Conduct monitoring
                     monthly between April and September. Spot treat Reed Canary Grass, Canada thistle and other problem
                     species as needed.

                     Monitor for weeds in April, June, and August. Spot spray perennial weeds as necessary. Collect seed
                     from established areas and re-seed sparse areas as needed.

                     Monitor for weeds in April, June, and August. Spot spray perennial weeds as necessary. Collect seed from
                     established areas and re-seed sparse areas as needed.

                     Conduct prescribed burn of uplands in May. Monitor for weeds in April, June, and August. Spot spray
                     perennial weeds as necessary. Collect seed from established areas and re-seed sparse areas as needed.

   Future            Continue monitoring and spot treatment of weeds and conduct burning on a 3-5 year rotation. Collect
   Maintenance       seed from established areas and re-seed sparse areas as needed.

Note: Maintenance schedule may need to be adapted to changing management needs. Dates are for south-
ern half of the state; northern half may be two weeks later.

It is often useful to have one master schedule that             It is not uncommon for restoration projects to get off
summarizes how the site preparation, planting,                  schedule. If a project gets off schedule due to weather,
and maintenance strategies will work together with              invasive species, or other variables, it is a good idea
site construction and the restoration of hydrology.             to revise project schedules. Make sure that everyone
This comprehensive schedule is often referred to as             understands the new project timeline and how it
an implementation schedule. Implementation                      influences specific restoration strategies, and contract
schedules help ensure that all stages of the project            payments.
are working together.

DECEMBER 2008                                                                         5  2 D E V E L O P I N G A V E G E TAT I O N P L A N   21
      Figure 5.30

22   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T   M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E

  5-3 Site Preparation

                                                                       The following site preparation strategies are
                                                                       discussed in this chapter:

                                                                         Clearing and Grubbing
                                                                         Sediment Removal
                                                                         Crop Production
                                                                         Perennial Vegetation Removal
                                                                         Tilling for Weed Control
                                                                         Seedbed Preparation
Figure 5.31 Diverse Native Vegetation
                                                                         Temporary Cover Crops

T    he vegetation establishment plan should include
     methods to prepare the site for planting. Site prepa-
ration involves the removal of undesirable vegetation
                                                                 During the site assessment of the project, existing
and the preparation of the soil surface for planting. Site
                                                                 conditions were evaluated. The condition of the site,
preparation strategies should be chosen based on in-
                                                                 prior land uses, crop types, herbicide uses, and extent
formation that was collected during the site evaluation
                                                                 of existing vegetation all will influence the site prepara-
related to: existing soils, hydrology, invasive vegetation,
                                                                 tion strategies needed. If diverse native vegetation is
seedbank potential, and remnant native vegetation.
                                                                 the goal, strategies should be chosen to ensure thor-
The planting strategies to be used, along with vegeta-
                                                                 ough site preparation and long-term control of prob-
tion goals and budget, will influence the selection
                                                                 lem species.
of site preparation strategies. Efforts to sufficienlty
prepare the site for planting will increase the potential
                                                                 Consider how site preparation, planting, and maintenance
for successful establishment of vegetation and limit the
                                                                 strategies will work together. For example, drill seed-
amount of aftercare needed.
                                                                 ing and broadcast seeding have different requirements
                                                                 for seedbed preparation. Site preparation may be
                                                                 conducted in a way that will utilize a native plant seed
                                                                 bank, influencing additional planting strategies and
                                                                 maintenance activities. Developing clear implementa-
                                                                 tion schedules will refine how the strategies will work
                                                                 together. It is common for several site preparation
                                                                 strategies to be combined for a single project.

Figure 5.32 Reed Canary Grass Dominated Wetland

DECEMBER 2008                                                                                          5  3 S I T E P R E PA R AT I O N   23
     The following table summarizes site preparation strategies to help make initial decisions about what might work
     best for a site and how strategies may be combined.

        Table 5.6 Comparison of Site Preparation Strategies Table 5.6 Comparis

        Technique                                      Use/Considerations                                Relative Costs

                                                       Involves the removal of undesirable trees         Medium/High – Costs vary greatly
                                                       and shrubs. This is often a first step before     depending on the type of equipment
        Clearing and Grubbing
                                                       other site preparation strategies are             being used and the density and size of
                                                       conducted.                                        the vegetation to be removed.

                                                                                                         High - involves use of heavy equipment
                                                       Sometimes recommended if it is likely that
                                                                                                         to excavate and move sediment. Costs are
                                                       a native seed bank will be exposed. Must
                                                                                                         particularly high if soil will be removed
        Sediment Removal                               have a good disposal option for the sedi-
                                                                                                         from the site. A high degree of precision
                                                       ment. Sediment removal may also aid in
                                                                                                         is required to expose native seedbanks—
                                                       the establishment of wetland hydrology.
                                                                                                         additional seeding may be required.

                                                       Used to remove the upper 8-12 inches of
                                                       soil along with invasive species (par-
                                                                                                         High - involves use of heavy equipment
                                                       ticularly reed canary grass) seeds and
                                                                                                         to remove the upper layer of soil. Costs
        Scraping                                       rhizomes. Disposal areas for scraped mate-
                                                                                                         are particularly high if scraped material
                                                       rial are necessary. Scraping is not recom-
                                                                                                         will be removed from the site.
                                                       mended when it will disturb an intact
                                                       wetland substrate.

                                                       Planting Roundup ready corn or soybeans
                                                                                                         Low - Typical crop planting costs; can be
        Crop Production                                for a year or two before seeding is a com-
                                                                                                         recouped after harvest.
                                                       mon strategy to control perennial weeds.

                                                                                                         Medium - Herbicide application costs
                                                       Herbicide is used to remove perennial
                                                                                                         range from $15 to $80 per acre depend-
                                                       vegetation. Tilling in combination with
        Perennial Vegetation Removal                                                                     ing on the herbicide applied, application
                                                       herbicide removes aggressive species and
                                                                                                         technique, and the number of acres to
                                                       prepares for broadcast seeding.
                                                                                                         be treated.

                                                       Conducted after herbicides control peren-
                                                       nial weeds or on fields coming out of
                                                       agricultural production where weeds are           Low - can vary depending on the number
                                                       controlled. Keep tilling to a minimum to          of times tilling is conducted.
        Tilling for Weed Control
                                                       prevent weed germination and disrup-              Each tilling costs between $6-$40 per
                                                       tion of soil structure and organisms. Some        acre ($6-$20 is common).
                                                       tilling may be necessary in preparation of
                                                       broadcast seeding.

                                                       Successful broadcast and drill seeding
                                                       requires a firm seedbed. Wetland sites can
                                                       be prepared by light disking; harrowing
                                                                                                         Low –between $10-$50 per acre
        Seedbed Preparation                            can also be conducted. A combination
                                                                                                         ($10-$20 is common).
                                                       of disking, harrowing, and cultipacking
                                                       before drill seeding ensures a firm soil

24   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                                        M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
Clearing and Grubbing                                          Typical Strategies
                                                               The selection of tree and shrub removal methods
                                                               depends on site conditions, the availability of equip-
                                                               ment and the level of disturbance that is acceptable for
                                                               the site. On sites where additional soil movement will
                                                               occur, bulldozers may be the most efficient method
                                                               to remove unwanted vegetation. On sites where soil
                                                               disturbance will disrupt soil structure, microorganisms,
                                                               native seedbank, and other propagules, less intensive
                                                               methods such as chainsaws and brush cutters are a bet-
                                                               ter option. Brushhogs are sometimes used in the winter
                                                               when the ground is frozen to remove buckthorn. Buck-
Figure 5.33 Cleared Trees and Shrubs                           thorn and many other weedy species require treatment
                                                               with herbicide to prevent re-sprouting. See Appendix
Overview                                                       5-A for control information for specific invasive spe-
                                                               cies. Slash is commonly burned after removal and there
Clearing and grubbing involves the removal of trees and        is an increasing demand for woody vegetation from
shrubs from a project site prior to other site preparation     bioenergy production. When burning, piles should be
activities. Disturbed wetlands in Minnesota often become       stacked tightly to ensure an efficient burn. Appropriate
dominated by trees and shrub species after hydrology           burn permits must be obtained.
is altered. Commonly encroaching trees and shrubs are
quaking aspen, sandbar willow, American elm, boxelder,         Influence on Other Strategies
Siberian elm, and common and glossy buckthorn. In prai-
rie regions of the state, fire historically controlled trees   The removal of species such as buckthorn that create
and shrubs in and around wetlands and prairies. With           dense shade can sometimes release the native plant
the suppression of fire, willows and other species have        seedbank and allow more desirable species to estab-
become more common in these ecosystems.                        lish from seed. Long-term maintenance is needed for
                                                               tree and shrub species that easily resprout or establish
The presence of trees and shrubs in the prairie region         readily from seed. Prescribed burning and mowing or a
can influence use by wildlife species. For example,            combination of both is useful for the long-term control
because trees act as perches for predators in wildlife         of trees and shrubs.
production areas, or areas managed for grassland
birds, they are sometimes discouraged in both wet-             Resources
land and upland areas in the prairie region of the state.
                                                               Mn/DOT Specification 2101,
Encroaching trees and shrubs can inhibit growth of   
desired species by creating competition for nutrients,
light, and water.                                              Link to Appendix 5-B, Cutting and Clearing
In northern Minnesota, forested wetlands are common
and trees and shrub are often promoted as part of res-
toration projects. The decision to remove existing trees
should be based on target plant community goals and
the influence that existing trees and shrubs will have on
the establishment of desired vegetation.

Bulldozers, chainsaws, brush cutters, weed wrenches,
brush hogs, logging equipment, front end loaders,
tractors, backhoes.

DECEMBER 2008                                                                                      5  3 S I T E P R E PA R AT I O N   25
                                                                  Influence on Other Strategies
                                                                  The removal of sediment may cause soil compaction
                                                                  that will then need to be loosened before seeding is
                                                                  conducted. Soil disturbance during sediment removal
                                                                  may allow for the germination of weeds, requiring their
                                                                  control before seeding.

                                                                  See Section 4, Project Engineering, Design and Construction
                                                                  for more information on sediment removal
                                                                  Wetland Restoration Guide for Wisconsin Landowners, 2nd Edition
     Figure 5.34
                                                                  Link to Appendix 5-B, Sediment Removal
     Sediment Removal                                             Specifications

     Overview                                                     Scraping
     The accumulation of sediment in wetlands can alter
     hydrology and bury seed of native species. In some           Overview
     wetlands, more than three feet of sediment has ac-
                                                                  Scraping involves removing the upper layer of soil to
     cumulated from erosion. Sediment can be removed
                                                                  remove invasive plant seeds and rhizomes and in some
     to expose a native seedbank but this practice requires
                                                                  cases to expose native seedbank. Scraping is most
     careful planning and skillful removal of soil. Excavation
                                                                  often used to remove reed canary grass mats, though it
     and removal of soil can be expensive and impractical,
                                                                  is also a common technique to create open water areas
     particularly if removed sediment must be hauled a long
                                                                  in wetlands.
     distance. Additional discussion on this practice occurs
     in Section 4 – Engineering Design.
     Equipment/Materials                                          Excavators, bulldozers, scrapers.
     Excavators, bulldozers, scrapers.

     Typical Strategies
     Refer to Section 3-3 Assessment of Site Soils, Soil
     Mechanics and Construction Issues for information on
     how to evaluate sediment depths. Excavation should
     be conducted by qualified operators to maximize the
     exposure of the remnant seedbank. Excavating to the
     correct depth can be difficult and is rarely relied on as
     the only strategy to establish native vegetation. The in-
     stallation of additional seed is recommended to ensure
     successful establishment of diverse vegetation. Sedi-
     ment that is removed during excavation should be used        Figure 5.35
     onsite if possible to minimize costs; one potential use is
     the filling of ditches.                                      Typical Strategies
                                                                  Scraping is a technique that can be used to remove
                                                                  reed canary grass mats. The root depth of reed canary
                                                                  grass will vary (between six and twelve inches) so the
                                                                  appropriate depth of scraping should be checked by

26   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                   M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
project designers during the development of the veg-          be planted for an additional season. After harvesting
etation plan. Depth should also be checked periodically       corn, stubble needs to be cut and baled, as it will inter-
during the scraping to make sure that all rhizomes are        fere with planting
being removed.
                                                              Glyphosate is a contact herbicide that does not persist
Existing hydrology levels will often influence whether        in the soil, so there is not a risk to new seedlings. Fields
large equipment can be used. Scraping can also be             may need to be sprayed once in the spring before
conducted early or late winter; it is most effective when     planting to kill newly establishing weeds. If small grains
frost depths are approximately the same as the desired        are harvested in the summer, the field can be sprayed
removal depth. The scraped material containing reed           once or twice followed by seeding in the fall (Fuge
canary grass seeds and rhizomes needs to be removed           2000). If the site will be seeded with a drill, no addition-
from the site or buried to prevent re-establishment.          al tilling is required. If the site will be broadcast-seeded,
                                                              such as for wetland areas, additional disking and pos-
Influence on Other Strategies                                 sibly harrowing may be necessary.
Scraping may cause soil compaction that will then need
to be loosened before seeding is conducted. The scrap-
ing process may expose a native seedbank at a site and
provide a local source of vegetation. Like sediment
removal, scraping may allow for the germination of
weeds that will need to be controlled before seeding.

See Section 4, Engineering Design and Construction for more
information on scraping
                                                              Figure 5.36 Boom Application of Herbicide

Link to Appendix 5-B, Scraping Specifications

                                                               Table 5.7 Site Preparation Schedule for Fields
Crop Production                                                in Agricultural Production

Overview                                                       September             Harvesting (with bailing of stubble
                                                                                     if in corn)
The planting of herbicide ready corn or soybeans
for one or two years before seeding a site can be an           Mid-October           Cultivation with double discs or field
effective method to prepare for seeding. Repeated                                    cultivators to break soil into smaller chunks
                                                                                     (two to three passes at right angles)
herbicide applications that are part of the crop produc-
tion process can effectively remove weed seedlings.
                                                               Mid-October           Harrowing upland areas to even out
This technique should not be used if a native species                                irregularities
seedbank may be present as it will deplete the seeds of
native species as well as those of weeds.                      Mid-October           Broadcast Seeding

Equipment/Materials                                            Mid-October           Cultipacking or Rolling

Plow, disk, planter, tractor, boom sprayer, combine.           Note: Spring seeding can also be conducted following crop production;
                                                               the same site preparation techniques apply for spring planting, though
                                                               an herbicide application would be required before tilling if weeds
Typical Strategies                                             germinated after fall harvest. Timing and techniques vary depending
                                                               on weather and site conditions. If drill seeding, no additional tilling is
In the case of cornfields where Atrazine (an herbicide         necessary unless the ground is uneven.
that can inhibit growth of native plants) has been ap-
plied, it is recommended that Roundup ready soybeans

DECEMBER 2008                                                                                                5  3 S I T E P R E PA R AT I O N   27
     Influence on Other Strategies
     Crop production may require additional soil treatment
     such as harrowing to prepare the seedbed for planting.
     If there is a period of a month or longer after harvest
     before a fall seeding is conducted, additional herbicide
     application may be needed to remove weeds. Con-
     servation program requirements should be checked
     to make sure that the uses of herbicides are allowed.
     Herbicide use may also be restricted near organic farm-
     ing operations.
                                                                  The impact of herbicide application on non-target plant
     Resources                                                    species and other organisms limits its use in some situa-
     University of Minnesota Extension,                           tions. If all vegetation will be removed from a site, the                    effect on non-target plant species is less of a concern
                                                                  but there may still be some influence on soil microflora
                                                                  and fauna. It is essential that only aquatic certified her-
     Perennial Vegetation Removal                                 bicides be used near water. Some grass-specific herbi-
                                                                  cides currently being used for reed canary grass control
     Overview                                                     do not have aquatic certification.
     The removal of existing perennial vegetation is often
     desired and necessary to prepare a site for planting. It     Equipment/Materials
     includes the select removal of identified species (i.e.      There are many types of herbicide to choose from;
     reed canary grass) or the removal of a whole field of        some target broad-leaf weeds while others target grass-
     existing, undesirable vegetation (i.e. smooth brome          es. Broad-spectrum herbicides target both broad-leaf
     grass). The removal of existing vegetation generally         weeds and grasses. Herbicide should be selected based
     involves herbicide application or a combination of her-      on the type of vegetation to be removed. Appendix 5-A
     bicide application and tilling. Herbicide application is     contains a table that compares herbicides commonly
     often the most cost-effective strategy to remove peren-      used for natural resource management. Herbicide is ap-
     nial vegetation in both uplands and wetlands.                plied with booms, backpack sprayers and wands. Tilling
                                                                  involves the use of plows, disks, and harrows.

                                                                  Typical Strategies
                                                                  Methods of perennial vegetation removal vary de-
                                                                  pending on weed species present, herbicide type, and
                                                                  whether tilling is conducted.

                                                                  Controlling Invasive Species - The long-term con-
                                                                  trol of reed canary grass is particularly problematic in
                                                                  wetland restorations. Other invasive species that can be
                                                                  problematic include hybrid cattail, purple loosestrife,
                                                                  Canada thistle, and wild parsnip, among others. If not
                                                                  controlled thoroughly before seeding, invasive spe-
                                                                  cies may lead to project failure or decreased diversity
     Figure 5.37 Reed Canary Grass                                and abundance of native species. In instances where
                                                                  desirable native species are present, spot treatment
                                                                  with broad-spectrum herbicides may be used (avoiding
                                                                  desirable species) or herbicides that specifically target
                                                                  grasses or broad-leaf species.

28   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                  M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
Appendix 5-A contains additional discussion and spe-         First cut and mow remove existing vegetation at a low
cific techniques on how to remove each of the invasive       setting (4-6 inches). After mowing, allow vegetation to
species in the following list. Many of the control strate-   grow 10 to 12 inches tall, and then apply a two to four
gies presented for these species can be used for project     percent solution of glyphosate (depending on species
maintenance as well as for site preparation.                 present/see label specifications). If the vegetation and
                                                             thatch layer is thick, a burn is recommended. Burn-
Hybrid cattail (Typha glauca)                                ing can eliminate some weed seeds while improving
Narrow-leaf cattail (Typha angustifolia)                     effectiveness of subsequent herbicide treatments. If
Purple loosestrife (Lythrum salicaria)                       regrowth occurs, herbicides should be applied again
Reed canary grass (Phalaris arundinacea)                     when weeds are 10 to 12 inches high.
Common buckthorn (Rhamnus cathartica)
Glossy buckthorn (Frangula alnus)                            After successful die off from the herbicide application,
Common reed grass (Phragmites australis, syn. P.             till the field to stimulate and germinate any remaining
communis)                                                    weed rhizomes and produce green growth. Tilling can
Canada thistle (Cirsium arvense)                             be conducted with a disc or tractor-mounted cultivator
Crown vetch (Coronilla varia)                                to a depth of four to five inches. If weed seeds germi-
Bird’s foot trefoil (Lotus corniculatus)                     nate, the site should be tilled again or additional her-
Sweet clover (Melilotus officinalis and M. alba)             bicide applied. Additional tilling should be conducted
Wild parsnip (Pastinaca sativa L.)                           if broadcast seeding is planned. Additional herbicide
Spotted knapweed (Centaurea maculosa)                        should be applied if the site will be drill seeded. When
                                                             conducting additional tilling, do it every two to three
Prepared Fields Dominated with Perennial Vegeta-             weeks until the site is ready for planting. It is important
tion - Upland fields, such as those in CRP, that have        to till every two weeks during May, June, and July, as
been out of production for several years, are often          many rhizomatous weeds such as quack grass may con-
dominated with weedy and invasive grasses such as            tinue to thrive. This sequence of site preparation should
smooth brome, timothy, redtop, Kentucky bluegrass,           be started in late May to allow enough time to prepare
and goldenrods. Transitioning old fields to soybeans         the site for a fall dormant seeding. If spring seeding is
for two years will aid in the removal of these nuisance      planned, a final one-inch deep till or an herbicide ap-
species and weeds. If agricultural production is not an      plication is recommended after the first good rain to kill
option due to site conditions or program restriction, the    germinating weeds before they emerge (Fuge 2000).
following sequence is recommended:                           Broadcast seeding can be conducted on a prepared
                                                             seedbed. A cultipacker should be used on a site prior to
                                                             seeding if the site has recently been tilled and a no-till
                                                             drill will be used.

                                                             Tilling alone can be used for removing perennial veg-
                                                             etation but it must be conducted every two to three
                                                             weeks during an entire growing season. Increased fuel
                                                             costs, breakdown of soil structure, impacts on soil mi-
                                                             croorganisms, and erosion risk often make this option
                                                             less desirable (Fuge 2000).

Figure 5.38 Smooth Brome Grass

DECEMBER 2008                                                                                    5  3 S I T E P R E PA R AT I O N   29
                                                                              The following is adapted from a schedule that has
      Table 5.8 Site Preparation Schedule for Fields                          been developed by Habitat Forever, LLC. It is a variation
      Dominated by Perennial Vegetation (Option 1)                            of the sequence listed above and works well against
                                                                              healthy stands of brome grass.
      Late May                    Mow to reduce vegetation height

      June/July                   Spray 2%-4% solution of glyphosate           Table 5.9 Site Preparation and Establishment
                                  with surfactant as weeds reach 10-12
                                                                               Schedule for Fields Dominated with Perennial
                                                                               Vegetation (Option 2)
      July                        Burn (optional)
                                                                               Early June                              Disk in two directions to level
                                                                                                                       surface and stress brome
      August                      Spray 2%-4% solution of glyphosate
                                  with surfactant as weeds reach 10-12
                                                                               Early August                            Mow* to reduce veg. height
                                                                                                                       to stimulate fresh growth
      August/Sept.                Till soil with disc or tractor mounted
                                                                                                                       and enhance herbicide kill
                                  cultivator 4-5” deep

                                                                               Mid September                           Spray 2%-4% solution of
      Sept until seeding          Till every two weeks until planting
                                                                                                                       glyphosate with surfactant

      Mid-October                 Pack with cultipacker to create firm
                                                                               Late October                            Heavy tillage** to tear up
                                  seed bed
                                                                                                                       brome sod

      Mid-October                 Conduct seeding with native grass drill
                                                                               Early May (year 2)                      Disk to reduce lumps (on
                                                                                                                       lighter soils or with less sod,
      Planting can also be conducted in the spring but additional weed con-                                            may not be necessary)
      trol may be necessary prior to seeding.

                                                                               Early May (year 2)                      Field cultivate to create
                                                                                                                       smooth, level seed bed

                                                                               Early May (year 2)                      Pack with cultipacker to cre-
                                                                                                                       ate firm seed bed

                                                                               May/June (year 2)                       Conduct seeding with native
                                                                                                                       grass drill, seed after 1st flush
                                                                                                                       of annual grasses and broad-
                                                                                                                       leaves are 3-4” high

                                                                               5-7 days post seeding                   Apply glyphosate herbicide
                                                                                                                       to kill all emerging competi-

                                                                               As vegetation reaches 15-18             Chop/mow 2-3x during the
                                                                               inches                                  growing season to reduce
                                                                                                                       competition and allow
                                                                                                                       sunlight to penetrate to new

                                                                               *This mowing pass may not be absolutely necessary
                                                                               **”Heavy tillage” means a disk ripper, disk chisel, or equivalent (not
                                                                               moldboard plow or heavy disk)

     Figure 5.39 Mixed Perennial Weeds

30   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                                   M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
Removing Vegetation in Fields that                                Spring Peeper Meadow: Revegetation Practices in a Seasonal
Contain Sod                                                       Wetland Restoration in Minnesota, Bohnen, J.L., Galatowitsch, S.M.
                                                                  Reed Canary Grass Control Prescription Table,
Fields in sod should be treated with glyphosate herbi-  
cide similar to the strategy discussions above. Repeated          grass.control_prescription_table.pdf
herbicide applications may be required. In most cases
sites will not require cultivation unless broadcast seed-         Link to Appendix B, Herbicide Application
ing will be conducted. Once weeds have been killed                Specifications
with herbicide, the site can be planted with a no-till drill
(Fuge). In the case of sod, it is important that seed from
                                                                  Tilling for Weed Control
all seed boxes fall into slots cut by the seeder as seed
that falls on top of dead sod is unlikely to germinate. In
the case of sod farms where wetland hydrology will be
restored and the site will be broadcast seeded, tilling           Tilling the soil before seeding or planting will loosen
will be necessary to prepare the seedbed. The use of              soil that is too compacted for seed germination and
no-till drills without cultivation is a good method on            plant establishment. With a wetland planting, tilling will
sites with steep slopes, as the seed will be secured by           ensure that the soil is prepared for broadcast seeding.
the soil and roots and stems of dead plant material.              When tilling is conducted, eliminate perennial vegeta-
                                                                  tion to the extent possible through herbicide applica-
                                                                  tion before tilling is started (see schedules in previous
 Table 5.10 Site Preparation and Seeding
                                                                  section). Subsequent herbicide application may be
 Schedule for Removing Vegetation in Sod Fields
                                                                  conducted after tilling, particularly if seed drills will be
 Fall                       Glyphosate herbicide application
                                                                  used for planting.

 Mid-April                  Glyphosate herbicide application      Tilling is not necessary in every instance. It is not recom-
                            if necessary                          mended when soil disturbance may increase the threat
                                                                  of erosion or destroy soil microbes. Tilling can expose the
 Late April                 Seeding with a no-till drill to cut   seed of invasive species. It should be done as part of a
                            through sod                           thorough site preparation process that lasts a season or
                                                                  longer. Reed canary grass germinaton, in particular, can
 Note: Weeds should be thoroughly controlled before seeding
 is conducted
                                                                  be a problem when tilling moist soil (Kline 1997).

Influence on Other Strategies
A combination of herbicide application and tilling is
often recommended for the removal of weeds in situa-
tions such as old fields dominated with smooth brome
grass and for seedbed preparation of wetland areas in
preparation of broadcast seeding.

Best Management Practices for the Invasive Phalaris arundinacea
L. (Reed canary grass) in Wetland Restorations, Reinhart, C.H.,
Galatowitsch, S.M.                                                Figure 5.40 Disking
Native Vegetation in Restored and Created Wetlands, Its
Establishment and Management in Minnesota and the Upper
                                                                  Some degree of tilling is the norm for wetland restora-
Midwest, Shaw, D.B.                                               tion sites to prepare the seedbed for broadcast seeding
                                                                  and ensure good seed-to-soil contact. As a general rule,
Revegetation Practices in a Seasonal Wetland Restoration in
                                                                  decreased soil disturbance will result in less competi-
Minnesota, Bohnen, J.L., Galatowitsch, S.M.
                                                                  tion from weeds and may help maintain soil structure
Weed Control Methods Handbook Tu, M., Hurd, C.,                   and soil microorganisms. Wetland sites that were
Randall, J. (TNC)

DECEMBER 2008                                                                                             5  3 S I T E P R E PA R AT I O N   31
     previously in corn, soybeans, or a temporary cover crop
     typically require light disking at a minimum to prepare         Table 5.11 Tilling for Weed Control Schedule
     the seedbed. For upland sites, seed drills can be used          (transition from annual and biennial weeds)
     on fields that were previously in agricultural production
                                                                     Early April          Deep plow if the site has been in vegeta-
     without additional tillage as long as the surface is not
                                                                                          tion for one full season or longer.
     too rough.
                                                                     Late April           Disc or till site to 4-5 inches at earliest
     A relatively new practice is to avoid tilling wetland                                opportunity in spring or following spring
     areas (following crop production or other means of site                              plowing.
     preparation) in preparation of broadcast seeding in the
     winter (frost seeding). This is not recommended in areas        May – seeding        Disc, till, or harrow approximately every
                                                                                          two weeks 4-5-inches deep until seeding.
     where snowmelt will cause flowing or standing water.
                                                                                          If seeding right away, conduct seedbed
                                                                                          preparation and install seed.
                                                                     Note: Time and frequency of tilling may vary greatly depending
     Plows, discs, harrows, cultivators.                             on site conditions

     Typical Strategies
     Annual and biennial vegetation can be removed from             Influence on Other Strategies
     a site through repeated tilling. Consider this strategy        Additional seedbed preparation may be necessary after
     for fields that were recently in agricultural production.      tilling. Tilling may allow weeds to germinate, requiring
     Repeated tilling involves working up the soil every two        additional site preparation strategies to control weeds.
     or three weeks to a depth of four to five inches with a        When no-till drills will be used for seeding, tilled fields
     disc or rototiller. If there are many weed seeds at the        are often treated with herbicide as the final treatment.
     surface, deep plowing may be beneficial. When peren-           This minimizes the amount of soil disturbance and po-
     nial weeds are present, it is important to till every two      tential weed germination. Seeding is recommended to
     or three weeks, as rhizomes can spread with longer             be conducted one week after herbicide application.
     intervals. In some cases, this treatment needs to be con-
     ducted for a year or more, particularly when a field has       Resources
     been in perennial weeds for several years. There is a risk
     of erosion on sites that are tilled repeatedly; as a result,   Going Native, A prairie restoration handbook for Minnesota Land-
     this technique should not be used near waterways or            owners, Fuge
     on hilly sites.                                                The Tallgrass Restoration Handbook for Prairies, Savannas, and
                                                                    Woodlands, Packard, S., Mutel, C.F.
                                                                    University of Minnesota Extension,

                                                                    Link to Appendix 5-B, Tilling Specifications

32   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                        M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
Seedbed Preparation                                                seeding establishment and optimal growing condi-

                                                                   Table 5.12 Seedbed Preparation Schedule for
                                                                   Broadcast Seeding

                                                                   Early-May          Rough disking of site

                                                                   Early-May          Cultivation with double discs or field cultiva-
                                                                                      tors to break soil into smaller chunks (two to
                                                                                      three passes at right angles)

Figure 5.41 Harrowing for Seedbed Preparation                      Early-May          Harrowing to even out irregularities.
Photo by Prairie Restorations, Inc
                                                                   Mid-May            Broadcast seeding followed by rolling or
                                                                                      cultipacking for seed-to-soil contact. If using
Overview                                                                              a seed drill, see table below.
The purpose of seedbed preparation is to create ideal
                                                                   Note: Timing and techniques may vary depending on weather and site
growing conditions for seedling emergence and                      conditions. If field was in wheat, the site should be disked twice the
growth. Techniques generally differ depending on hy-               previous season after harvest to decrease allelopathic effect, followed by
drology conditions, the type of seeder to be used, and             spring site preparation.

the time of year that seeding will be conducted.

Equipment/Materials                                                5.13 Seedbed Preparation Schedule for
Double disks, field cultivators, harrows, rollers, cultipackers.   Drill Seeding

Typical Strategies                                                 Mid-April          Rough disking of site

Following the removal of existing vegetation, sites that           Mid-April          Cultivation with double discs or field cultiva-
have been rough-disked or plowed will need additional                                 tors to break soil into smaller chunks (two to
steps to smooth the seed bed. Double disks or field cul-                              three passes at right angles)
tivators are used to break the soil into smaller chunks.
Two or three passes at right angles to each other is               Mid-April          Harrowing to even out irregularities
recommended. In some cases, wetland sites are broad-
                                                                   Mid-April          Rain, rolling, or cultipacking if necessary to
cast seeded following the use of double disks or field
                                                                                      firm seedbed
cultivators. It is more common however that harrows
are used after disking or cultivation to further break             Mid- May           Final herbicide application; or apply herbi-
up soil clods and smooth the surface in preparation                                   cide up to one week after seeding
of broadcast seeding. Brillion or Trillion seeders that
broadcast and then pack seed are generally used after              Late May/          Drill seeding
harrowing but further packing is generally needed for              Early June
seed drills. When preparing for drill seeding, footprints
                                                                   Note: Timing and techniques may vary depending on weather and site
should not leave an indentation of more than one inch              conditions. If field was in wheat, the site should be disked twice the
deep. Soil can be firmed with a cultipacker or roller to           previous season after harvest to decrease allelopathic effect, followed by
prevent seed from being buried too deep. Sometimes                 spring site preparation.
rainfall can accomplish this final packing.

Seeding should be conducted as soon after seedbed
preparation as possible, particularly for broadcast seed-
ing where a relatively loose seedbed is necessary for
DECEMBER 2008                                                                                                   5  3 S I T E P R E PA R AT I O N   33
                                                                          Temporary Cover Crops

                                                                          Temporary cover crops give some flexibility in dealing
                                                                          with vegetation management issues and allows time
                                                                          for the soils and hydrology of the site to stabilize. Cover
                                                                          crops also provide cover in preparation for fall seeding.
                                                                          Another use for temporary mixes is to provide short-
                                                                          term stabilization on sites where there has been distur-
                                                                          bance but it is expected that the permanent vegetation
                                                                          will re-establish from the seedbank. This is more likely
     Figure 5.42 Prepared Seedbed                                         to be successful in the northern part of the state and
                                                                          in the central Anoka sand plain area where agriculture
     Influence on Other Strategies                                        has not been as intensive (Jacobson 2006). Temporary
                                                                          covers can also be used stablize areas that will be inun-
     Seedbed preparation follows other site preparation
                                                                          dated after hydrology is restored.
     strategies. If site preparation and seedbed preparation
     are done well, the chances for successful vegetation
                                                                          Temporary cover crops can replace the need for mulch
     establishment will increase. It is important that soil is
                                                                          if they are disked into a site before planting. In cases
     stabilized during the final grading and seedbed prepa-
                                                                          where a no-till drill will be used, disking will not be nec-
     ration stages of a project. This may involve the use of
                                                                          essary before seeding. Temporary cover crops rooted
     erosion control fabrics for steep slopes and the use of
                                                                          into the ground have less risk of floating with rising
     temporary cover crops to stabilize soil.
                                                                          water levels than other mulches. There are added costs
                                                                          with the seeding of temporary cover crops, though
     Resources                                                            these costs may be compensated by decreased future
     Going Native, A prairie restoration handbook for                     maintenance and mulching costs as well as by sale or
     Minnesota Landowners, Fuge                                           use of the crop itself.
     Harvesting, Propagating, and Planting Wetland Plants, Hoag, C.J.
     Native Vegetation in Restored and Created Wetlands, Its Establish-
     ment and Management in Minnesota and the Upper Midwest,
     Shaw, D.B.
     Revegetation Practices in a Seasonal Wetland Restoration in Min-
     nesota, Bohnen, J.L., Galatowitsch, S.M.

     The Tallgrass Restoration Handbook for Prairies, Savannas, and
     Woodlands, Packard, S., Mutel, C.F.

     Link to Appendix 5-B, Seedbed Preparation Specifications

                                                                          Figure 5.43 Establishing Temporary Cover Crop

                                                                          It is common to plant a single cover crop such oats,
                                                                          wheat or other cereal crops particularly if the crop will
                                                                          be harvested. There may be advantages to planting
                                                                          multiple species at once to ensure that a dense cover
                                                                          will establish even if there are varying soil and mois-
                                                                          ture conditions. The State of Minnesota has cover crop
                                                                          mixes that have been designed to provide tempoeary

34   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                           M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
Figure 5.44 Slough Grass from a Temporary Cover Crop Seed Mix

stabilization of projects.                                  Resources
                                                            Restoring and Managing Native Wetland & Upland Vegetation,
Typical Strategies                                          Jacobson, R.
Cover crops are seeded with seed drills or by broadcast
seeding followed by packing. The seedbed needs to be
sufficiently prepared to ensure that good seed-to-soil      Link to Appendix 5-B, Temporary Cover Crop
contact will be accomplished during planting. Tempo-        Specifications
rary mixes can be seeded almost any time of the grow-
ing season, but typically will not perform well if seeded
outside of the growing season.

Influence on Other Strategies
Temporary cover crops provide time to see if problem-
atic species have been adequately controlled, allowing
for additional site preparation before seeding. Tempo-
rary cover crops that are established prior to permanent
seed mixes can also be used as mulch if incorporated
through disking, eliminating the need for additional
mulch after seeding. Perennial temporary covers typi-
cally need herbicide treatment or disking to reduce
competition with permanent mixes.

DECEMBER 2008                                                                                   5  3 S I T E P R E PA R AT I O N   35
         Figure 5.45 Prairie Blazingstar

36   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T   M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E

  5-4 Establishing Vegetation in Uplands

                                                                      This chapter includes information on the
                                                                      following upland planting strategies:

                                                                         Broadcast Seeding
                                                                         Seed Drills
                                                                         Containerized Plants and Rootstock
                                                                         Upland Trees and Shrubs
                                                                         Bacterial and Mycorrhizal Inoculum
                                                                         Stabilizing Upland Soils

Figure 5.46

A    reas of upland buffer are included with most
     wetland restoration or creation projects and need
to be considered in the overall strategies for design,
                                                                 species. Although the planting of prairies has been a
                                                                 common practice for many years, there is still more to
                                                                 be learned related to seed mix development, the role
implementation, and maintenance of the project. The              of microorganisms, and how best to use strategies such
upland buffer is considered to begin at the boundary of          as mowing, prescribed burning, and grazing. Current
wetland dependent vegetation and extends upslope to              knowledge of these practices, along with new tech-
the boundaries of the project.                                   niques for growing trees and shrubs, are summarized in
                                                                 this chapter.
The establishment and maintenance of upland buffers
are important components of any healthy wetland eco-             The upland buffer around a wetland should be as large
system. Upland buffers provide many project benefits             as the site will accommodate to protect the wetland
and functions including:                                         from surround landuse disturbances and to prevent
                                                                 predation of nesting wildlife.
  Erosion protection
                                                                 When there are steep slopes around a wetland, it can
  Reduction of sediment, nutrient and pollutant loads
                                                                 be beneficial to establish vegetation in the upland
  to wetlands improving water quality
                                                                 buffer areas before planting the wetland. This allows
  Habitat corridors                                              time to stabilize uplands and minimize the risk of sedi-
                                                                 ment from uplands covering expensive wetland seed.
  Food sources as well as nesting, breeding, and winter
                                                                 Establishing uplands first can also allow for additional
  cover habitat and shelter for animals
                                                                 weed control in wetlands. The strategies used to restore
  Reduction of invasive species                                  uplands are often similar to wetland restoration strate-
                                                                 gies, though seed drills are commonly used to seed
Upland buffers can consist of a variety of habitats in-          uplands and are not recommended for wetland seed-
cluding prairie, savanna, and forest plant communities.          ing. Broadcast seeding can be used for both wetlands
Recommendations are included in the following sec-               and uplands.
tion for planting trees and shrubs in addition to prairie

DECEMBER 2008                                                                        5  4 E S TA B L I S H I N G U P L A N D V E G E TAT I O N   37
        Table 5.14 Comparison of Upland Vegetation Establishment Strategies

        Technique                              Use/Considerations                                Relative Costs

        Broadcast Seeding                      Eliminates the row effect that results from       Medium - Depends on project size, seed
                                               drill seeding. Tends to require more seed than    source, mix diversity, and individual plant
                                               drill seeding but provides better growing         species included in mixes.
                                               conditions for forbs. Can be conducted in
                                               the dormant season, extending the seeding

        Seed Drills                            Used when soil disturbance may improve            Medium – Depends on project size, seed
                                               growing conditions for weed seeds or pro-         source, mix diversity, and individual plant
                                               mote erosion. Also effective when planting        species included in mixes.
                                               into cover crops. Requires less seed than
                                               broadcast seeding and tends to favor grasses
                                               over forbs.

        Containerized Plants                   Planted in uplands to increase diversity and      High - costs for installation varies widely due
        and Rootstock                          provide faster establishment in visible por-      to the size and type. Some rough costs: Plug
                                               tions of projects or areas prone to erosion.      installation: $1.75 to $2.10/plant installed
                                               Used often for species that do not develop        4” container installation: $5.00-$7.00/plant
                                               well/quickly from seed.                           installed Bare root plants:$2.00 to $3.00

        Upland Trees and                       Planted to improve wildlife habitat and           High/Medium - Varies greatly depending on
        Shrubs                                 restore savanna and forested plant communi-       the size and type of plant material. Direct
                                               ties. The type of plant material varies widely    seeding of tree and shrub seed - $650-850
                                               from seed, seedlings, whips, larger bare root     per acre (including site preparation, seed,
                                               plants, and containerized plants ranging from     and seeding)Bare root trees/shrubs: $3-$15
                                               2-gallon containers to 25-gallon containers, as   installed, each Containerized trees/shrubs
                                               well as balled and burlapped trees.               $25.00-$100.00 installed, each

        Bacterial and                          Necessary to ensure the establishment of          Low – Incorporating bacterial or mycorrhizal
        Mycorrhizal                            upland legumes. Mycorrhizal inoculum can          inoculums tend to be relatively low per acre
        Inoculum                               improve the growth and health of many
                                               upland species.

        Stabilizing Uplands                    Often essential to minimize erosion that can      Medium – Varies depending on the tech-
                                               bury and prevent the germination of wet-          nique chosen. Rough costs for upland
                                               land seed. Also prevents the loss of seed in      mulching at 2-tons per acre are $250 to $450
                                               sloping upland areas and provides improved        per acre
                                               conditions for seedling establishment. Can
                                               be accomplished by using mulches, tempo-
                                               rary cover crops and permanent seed mixes.
                                               Establishing uplands first can give more time
                                               for wetland weed control before planting.

38   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                                   M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
Broadcast Seeding                                             Therefore, to achieve uniform coverage it is often
                                                              necessary to separate out smaller seeds and plant
                                                              them separately.
                                                              Broadcast seeding is not recommended in areas that
                                                              will likely be flooded or have flowing water that will
                                                              prevent establishment.

                                                            Broadcast seeding is conducted with agricultural
                                                            broadcast seeders, ATV mounted seeders, and Vicon-
                                                            type seeders adapted to spread mixes of a variety of
                                                            seed sizes. Helicopters and airplanes have also been
                                                            used for broadcast seeding in areas with saturated soils.
Figure 5.47 ATV with Broadcast Seeder
                                                            Sand or other inert carriers are commonly mixed with
Overview                                                    seed to make broadcast seeding easier. Packing is con-
Broadcast seeding for upland vegetation establishment       ducted with cultipackers and drum or helicoil packers
involves spreading seed by hand or by a variety of types    (Fuge 2000).
of mechanical equipment on the soil surface. Broadcast
seeding is typically followed by packing the seedbed to     Typical Strategies
achieve good seed-to-soil contact.
                                                            Broadcast Seeding (Fall and Mid to Late Spring) –
                                                            Both fall and spring plantings are common for upland
Advantages:                                                 sites. Spring plantings are generally conducted be-
  Broadcast seeding prevents the row effect left by         tween mid-April and late June. Fall planting of uplands
  seed drills                                               can be done between mid-October and freeze-up of
                                                            the soil surface. Fall planting is considered to result in
  Broadcast seeding can be conducted with seed that         the most successful germination of forbs because seed
  has not been cleaned (wild harvested). This is a          stratifies over winter. Fall planted prairies are less likely
  common practice for the Fish and Wildlife Service         to be dominated by warm-season grasses such as big
  and Minnesota Department of Natural Resources,            bluestem and Indian grass than spring planted ones.
  who harvest seed from remnant communities or              Warm-season prairie grasses will not germinate when
  established prairies to be spread on new restoration      mean soil temperatures are below 65 degrees Fahren-
  sites. A seed test for purity and germination is recom-   heit, so they normally will not germinate in late fall and
  mended when using wild harvested seed to deter-           early spring.
  mine seeding rates.
   Broadcast seeding does not require the soil to be        When broadcast-seeding, carriers such as cracked corn
  tilled before planting and therefore is useful in areas   or sand can be added to seed mixes to make seed
  where the soil should not be tilled due to the risk of    dispersal easier and make it easier to see where seed
  erosion or germination of weeds and invasive spe-         has been spread. Carriers and seed can be combined in
  cies.                                                     barrels that are then sealed and rolled over the ground
                                                            surface for mixing. Seed can also be mixed with grain
   Broadcast seeding can be conducted in the spring,        shovels on a smooth, clean floor.
  fall, or winter.

   When using seed mixes that contain a variety of seed
  sizes, it has been found that the smaller seeds will
  tend to settle to the bottom of broadcast equipment
  when seeding is done as one operation (Fuge 2000).

DECEMBER 2008                                                                  5  4 E S TA B L I S H I N G U P L A N D V E G E TAT I O N   39
     When broadcast seeding, make two or three passes at
     right angles with a broadcast seeder to ensure that the
     entire site has been seeded. Sites should typically be
     cultipacked or rolled after broadcast seeding to ensure
     seed-to-soil contact. In some cases, large seed such as
     fluffy grasses are broadcast first followed by harrow-
     ing and then small forb seed is broadcast followed by
     cultipacking. As a general rule, seed shouldn’t be buried
     deeper than one-half inch and small seed should be at
     the surface. Rolling firms the soil around the seed and      canary grass growth if washed into wetlands. Lime is
     reduces moisture loss during germination.                    not necessary if soil pH is 5.5 or higher.

                                                                  Broadcast Seeding (Early Spring) - Another option for
                                                                  broadcast seeding is to conduct the seeding followed
                                                                  by an early spring prescribed burn. This strategy has
                                                                  been used by the Detroit Lakes Fish and Wildlife Service
                                                                  Office in situations where extensive site preparation
                                                                  is not possible (Hanson & Kahan 2008). The following
                                                                  steps outline the process for early spring broadcast

                                                                    Conduct an early spring prescribed burn where you
                                                                    wish to change the vegetative community.
                                                                    Seed directly into the ash the next day.
                                                                    When the existing non-native vegetation reaches
                                                                    four to eight inches, spray with a high rate (2 Qts.) of
                                                                    glyphosate & surfactant.
                                                                    Conduct another early spring burn again in four yrs.
     Figure 5.48 Tractor Mounted ATV Seeder
                                                                    Follow the burn with a glyphosate herbicide applica-
     Some upland projects will have had a temporary cover           tion (1 to 1.5 Qts.) when the non-native vegetation
     crop planted on them; the temporary cover may need             that remains reaches a height of one to two inches. If
     to be mowed down and an inter-seeder drill used to             any native species are up, they will not be affected by
     install the seed. If broadcast seeding will be conducted,      the glyphosate at this very early stage of growth.
     such as for wetlands, the temporary cover should be
     lightly disked before seeding. The temporary cover can       Broadcast Seeding (Winter) - There has been success
     often serve as mulch on these sites. If the permanent        with broadcast seeding of prairies late into the fall and
     seed mix will be installed immediately (no temporary         during the winter months when site conditions allow
     mixes), then mulching followed by disk anchoring is          it. Conditions are most suitable for this type of seed-
     recommended to protect seedlings.                            ing late into the fall or late into the winter when snow
                                                                  depths are limited or packed down. The natural freez-
     Fertilizers are typically not necessary when seeding         ing and thawing action helps set the seed firmly in the
     upland areas unless the soils are found to be low in         soil (eliminating the need for further packing), prepar-
     available nutrients. Low-nutrient soils should be tested     ing it for growth in the spring. This technique, often
     for available NPK (Nitrogen, Phosphorus, Potassium). If      referred to as frost seeding, should be conducted on
     phosphorus and potassium levels are low, use a 0-10-         a previously prepared seedbed. Frost seeding has also
     20 NPK analysis slow-release fertilizer applied at 60        been successful on sites where soybeans were recently
     pounds per acre. Nitrogen is not recommended when            harvested without additional site preparation. This
     establishing warm-season grasses because it can lead         technique is not recommended for areas that will likely
     to increased weed competition and can promote reed           be flooded or have flowing water the following spring.

40   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                  M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
The following are guidelines for winter seeding from              Seed Drills
the Detroit Lakes Wetland Management District (Prairie
Restoration Techniques/Tips, Hanson, L. Kahan, S.)                Overview
   Conduct a fall glyphosate herbicide application                Seed drills plant seeds in shallow slits in the soil surface
  (1 Qt.) or do this application in early spring prior to         that are created by the machinery. Seed drills are com-
  native emergence (timing is important)                          monly used on upland sites, particularly in situations
   Be ready to seed when conditions are right (have               where additional soil disturbance may cause erosion or
  seed and equipment ready)                                       weed germination.

   Seed late in the winter when sun has a higher angle
  (late Feb./March/early April)
  Pick partly to mostly sunny days with temperatures
  between 20° to 40° F
  Seed when there is less than one foot of snow
  Start work early so that seeding is done by 1:00 pm
  allowing time for sun to warm seed into the soil.
   Since this technique maximizes emergence of native
  forbs, post seeding mowing may not be needed.
  On soybean stubble most natives will attempt to                 Figure 5.49 Truax Seed Drill
  produce seed the first summer.
  If mowing is required, clip very high (18 to 30 inches).
                                                                    Seed drills place the seed below the surface so it is
Influence on Other Strategies                                       protected and has good seed-to-soil contact, result-
                                                                    ing in high germination rates and as a result, less
The broadcast seeding of uplands usually involves
                                                                    seed required than with broadcast seeding.
the tilling of soil, increasing the opportunity for weed
seeds to germinate. Weed control should be conducted                Seed drills do not require the soil to be tilled before
before seeding until problematic weeds are controlled.              planting and therefore are useful in areas where the
Refer to Section 5-3 for more information about weed                soil should not be tilled due to the risk of erosion or
control. Stabilizing the upland areas either before or              the germination of weeds and invasive species.
after the seeding is recommended to protect seedlings               Seed drills do not disturb existing, desirable
from wind and drying (see the strategy discussion in                vegetation.
this chapter on Stabilizing Upland Soils).
                                                                    Seed drills are limited to areas where heavy
The Tallgrass Restoration Handbook for Prairies, Savannas, and
Woodlands, Packard, S., Mutel, C.F.
                                                                    equipment can be used.

Going Native, A Prairie Restoration hHndbook for Minnesota          Very clean seed is needed to avoid clogging the
Landowners, Fuge E.                                                 seed drill.
Restoring Canada’s Native Prairies: A Practical Manual, Morgan,      Seed drills require a relatively firm bed for planting
J.P., Collicutt, D.R. and Thompson.                                 and thus some site preparation work may be needed
Prairie Restoration Techniques/Tips, Detroit Lakes Wetland          (i.e. cultipacking).
Management District, Hanson, L, Kahan, S.
                                                                    Seed drills can favor the germination of grasses
Link to Appendix 5-B, Broadcast Seeding                             over forbs, influencing diversity.
Uplands Specifications                                              Seed drilling is limited to spring or fall seasons.

DECEMBER 2008                                                                        5  4 E S TA B L I S H I N G U P L A N D V E G E TAT I O N   41
     Equipment/Materials                                             Influence on Other Strategies
     Truax, Tye, Nesbit, Great Plains, and John Deere Range-         The drilling of seed can decrease maintenance needs
     land seeders are all used for drilling seed. Native seed        due to less soil disturbance than is required for broad-
     drills have been constructed to accommodate different           cast seeding, resulting in less weed germination.
     shapes and sizes of seed and use small plows or disks
     to open furrows for the seed. Seed drills also cover the        Resources
     seed with soil and pack with rubber rollers to ensure
                                                                     A Landowner’s Guide to Prairie Management in Minnesota, Sve-
     good seed-to-soil contact (Fuge 2000).
                                                                     darsky, W.D., M.A. Kuchenreuther, G.J. Cuomo, P. Buesseler, H.
                                                                     Moechnig, and A. Singh.
     Seed drills can be rented from many Soil and Water
                                                                     The Tallgrass Restoration Handbook for Prairies, Savannas, and
     Conservation Districts (SWCDs) for a reasonable fee.
                                                                     Woodlands, Packard, S., Mutel, C.F.
     Also, many native plant nurseries and commercial seed
     farms do custom seeding for a fee.                              Going Native, A Prairie Restoration Handbook for Minnesota
                                                                     Landowners, Fuge

     Typical Strategies                                              Restoring Canada’s Native Prairies: A Practical Manual, Morgan,
                                                                     J.P., Collicutt, D.R. and Thompson.
     Seed drills require a seed bed that is relatively firm. Sites   Restoring the Tallgrass Prairie: An Illustrated Manual for Iowa and
     that were recently tilled should be cultipacked or rolled       the Upper Midwest, Shirley S.
     to ensure a firm seed bed for planting. As they can cut
     though stubble effectively, no-till drills work well on         Establishment of Native Grasses & Forbs (645) NRCS Biology Job
                                                                     Sheet #9
     sites that have been in agricultural production Drill
     seed directly into existing crop residue or vegetation
                                                                     Link to Appendix 5-B, Seed Drill Specifications
     or after the site has been cultivated and packed. The fol-
     lowing are recommended guidelines for drill seeding:

                                                                     Containerized Plants and Rootstock
        Ensure the seedbed is properly packed.
        Use a seed drill designed for native seed.                   Overview
        Keep the tractor speed at 2-3 miles per hour.                Species that do not germinate well from seed are
        Attempt to seed shortly before a rain                        often planted as containerized plants and rootstock
                                                                     (bare root plants and transplants) to increase species
        Keep the seedbox at least 1/3 full.
                                                                                                     diversity. Containerized
        Plant no deeper than ¼ inch.                                                                 plants and bare root
                                                                                                     material add costs to
        Seed widely over the entire site and then make
                                                                                                     projects and therefore
        passes over smaller areas to place specialized species
                                                                                                     are not used extensively
        (Galatowitsch and van der Valk 1994).
                                                                                                     for large areas.
         Mowing of weeds with a rotary mower is very                                                 Containerized plants may
        important the first year and may be needed in the                                            be used for areas that
        second year.                                                                                 will not germinate well
                                                                                                     from seed such as areas
     If weeds are germinating around the time that seeding           Figure 5.50 Photo by Rrairie that will have periods of
     is conducted, the weeds can be sprayed a week before            Restorations, Inc               flowing water.
     seeding or within five to seven days after seeding.
     Forbs can be seeded separately following drill seeding          Equipment/Materials
     of grases.
                                                                     Planting bars, Trowels, Spades, Shovels, Containerized
                                                                     plants, Bare root material.

42   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                        M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
                                                                 Restoring Canada’s Native Prairies: A Practical Manual, Morgan,
                                                                 J.P., Collicutt, D.R. and Thompson.
                                                                 Restoring the Tallgrass Prairie: An Illustrated Manual for Iowa and
                                                                 the Upper Midwest. Shirley S.
                                                                 Use of mycorrhizal inoculum as a soil amendment during
                                                                 prairie restoration. Tallaksen, HYPERLINK “http://www.hort.agri.

                                                                 Link to Appendix 5-B, Upland Containerized Plant and
                                                                 Rootstock Specifications
                                                                 Link to Appendix 5-C, Restoration Details/Diagrams

Typical Strategies                                               Trees and Shrubs
It is best to plant on a day with cool temperatures and
low winds. Minimize root exposure to drying conditions           Overview
by only exposing roots right before planting. Planting
                                                                 Trees and shrubs are planted in upland areas that
holes are commonly made with a planting bar that
                                                                 were historically forested, where the project goal is to
creates a hole about the size of the plug to be installed.
                                                                 increase connectivity between forests and to create
Root masses should be loosened before planting by
                                                                 wildlife habitat for forest species. Trees and shrubs add
hand or with a garden weeder and soil should be lightly
                                                                 cost to projects and require sufficient planning related
packed by foot, followed by watering. If possible, plant-
                                                                 to planting and long term-maintenance to ensure sur-
ing should be conducted before a rain, as rainfall can
                                                                 vival. Trees and shrubs often need protection from deer,
get plants off to a good start.
                                                                 rabbits, and mice.

Influence on Other Strategies
The planting of containerized plants does not change
the maintenance to be conducted at a site. The site
mowing that is recommended during the establish-
ment period can still be conducted. Containerized
plants may be influenced by mowing but should thrive
as long as mowing is not conducted below five inches.
The use of containerized plants may increase watering
needs; recently installed plants should receive approxi-
mately one inch of water per week between rainfall and
additional watering for at least the first month.

                                                                 Figure 5.51 Planting Bare Root Trees
A Landowner’s Guide to Prairie Management in Minnesota,
Svedarsky, W.D., M.A. Kuchenreuther, G.J. Cuomo, P. Buesseler,   Equipment/Materials
H. Moechnig, and A. Singh.
The Tallgrass Restoration Handbook for Prairies, Savannas, and
                                                                 Tree bars, Spades, Shovels, Containerized trees, Bare
Woodlands, Packard, S., Mutel, C.F.                              root trees.
Going Native, A Prairie Restoration Handbook for Minnesota
Landowners, Fuge

DECEMBER 2008                                                                         5  4 E S TA B L I S H I N G U P L A N D V E G E TAT I O N   43
     Typical Strategies                                           erized material tend to have higher survival rates than
                                                                  bare root trees and shrubs. Holes dug for containerized
     Planting Bare Root Upland Trees and Shrubs – Bare            plants should be 2.5 times the diameter of the con-
     root trees and shrubs come in a wide range of sizes          tainer. This will ensure that the roots will have room to
     from six-inch tall seedlings to ten-foot tall trees. Seed-   grow. It is most important that the hole is the widest
     lings are the most common type of bare root material         near the surface where fibrous roots will grow. It is also
     planted in upland projects. Generally, 100 to 500 bare       beneficial to scarify the edges of the hole to create a
     root trees/shrubs are planted per acre depending on          transition from the undisturbed soil to the backfill soil.
     the upland community type to be restored and the size        The adage, “give a $10 tree a $100 hole” provides a
     of material installed. When planting bare root trees and     good understanding of how important a properly dug
     shrubs, it is important to keep roots moist, to spread       hole is for tree growth.
     roots within planting holes, and to minimize air spaces
     around roots. Watering and/or planting before a rain is      Proper planting depth is very important with contain-
     also recommended.                                            erized plants. The “root flare”, or point where the roots
                                                                  flare out, should be no more than one inch below the
                                                                  surface after planting. Deeper placement can lead to
                                                                  roots that grow in a circular manner around the tree,
                                                                  causing tipping and constriction of the stem.

                                                                  Following are guidelines for planting containerized and
                                                                  bare-root wetland trees and shrubs in upland restora-
                                                                  tion sites:

                                                                    Plant on a day with low wind and cool temperatures,
                                                                    before a rain if possible.
                                                                    Keep roots moist and protected during transport and
                                                                    Dig planting holes at least twice the diameter of the
                                                                    root mass.
                                                                    When planting seedlings with spades or dibble bars,
                                                                    make holes large enough to accommodate spread-
                                                                    out root masses.
                                                                    Ensure the root collar of trees and shrubs is within
                                                                    one inch of the surface.
                                                                    Roughen the sides and bottom of the planting hole
                                                                    with a shovel.
                                                                    Loosen roots on the edge of containers and spread
                                                                    out roots of bare root material.
     Figure 5.52 Containerized Tree                                 After planting, add water, backfill half of the hole,
                                                                    add more water, and then add remaining soil.
     Planting Containerized and Ball and Burlap Wetland
     Trees and Shrubs - Containerized trees and shrubs              Lightly tamp the soil surface.
     can vary in size from one gallon containers to 25 gallon
                                                                     Add mulch if possible to retain moisture and
     trees. Large plants can also be obtained as balled-and-
                                                                    inhibit weeds.
     burlapped material. Cost is a limiting factor in the use
     of containerized and ball-and-burlap material. Contain-        Protect from deer, rabbits and mice as needed

44   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                  M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
Protecting Trees and Shrubs                                 tree seeds are stored, the greater the loss of viability.
                                                            The following are recommended collection and treat-
Upland trees such as white pine that are vulnerable to      ment methods for several common tree species:
deer browsing should be protected with fencing until
they reach a height of 15 feet. 14-gauge wire with 2x4
                                                              Walnuts should be collected and then stored in small
inch openings can be used to create exlosures around
                                                              piles, preferably in shade, to prevent excess heat pro-
individual trees or larger areas. Solar powered electric
                                                              duction. They can then be planted with husks intact.
fenscing can also be used to protect tree plantings.
                                                              Black walnut (Juglans nigra) should be planted at 10
                                                              to 15 bushels per acre (DNR 1998).
Bud caps can be used on
tree and shrub species to                                      Acorns should be collected soon after they fall and
prevent browsing. They are                                    immersed in water for 24 hours after collection. The
particularly important for                                    acorns should then be placed in a cool, dry loca-
seedling white pine but can                                   tion until planting. Red oak (Quercus rubra), bur oak
also protect deciduous trees                                  (Quercus macrocarpa), and shagbark hickory (Carya
and shrubs. Wire screening                                    ovata) should be planted at three to four bushels an
can also be placed around                                     acre. White oak (Quercus alba) acorns have not been
tree and shrub stems to pre-                                  successful in direct seeding project, it may be that
vent girdling from rodents.     Figure 5.53                   they cannot be held too long before seeding (Oakes
                                                              2008). It may be an option to to add white oak into a
Follow-up watering is important for establishing trees        project as seedling trees.
and shrubs. If soils are not saturated, plantings should       Ash and maple seeds should be air-dried and also
be receiving approximately one inch per week at a             stored in cool, dry conditions until planted. Green ash
minimum through rainfall or watering.                         (Fraxinus Pennsylvania), white ash (Fraxinus ameri-
                                                              cana), and hard maple (Acer spp.) should be planted
Direct Seeding of Upland Tree and                             at one bushel per acre.
Shrub Seeds
                                                              Cherry, sugar maple, and hickory are other species
Contributions from Duane Oakes, Oakes Forestry                that are sometimes added as seedlings.

Direct seeding of upland trees and shrubs can be a          Seeding rates of various tree species should ultimately
cost-effective method establishing woody species. High      be bases on availability of seed, plant community
stem densities will minimize loss due to deer and rab-      goals, and the strategies that are planned for commu-
bits. Several tree species such as oak, walnut, ash, and                                         nity establishment.
maple can be planted as acorns, nuts, or seedlings. This                                         Riparian and flood-
technique is sometimes used to establish savannas but                                            plain direct seeding
it can be a long-term effort requiring additional protec-                                        can be conducted
tion of seedlings from rodents, deer, and prescribed                                             with species such as
burning.                                                                                         cottonwood, silver
                                                                                                 maple, and ash.
Seeds or nuts from trees and shrubs are often collected
in and stored in feedbags to allow for air movement                                               The same techniques
and to discourage the growth of mold and fungus.                                                  that have been
Species such as black walnut (Juglans nigra), white oak     Figure 5.54                           described in the Site
(Quercus alba), northern red oak (Quercus rubra), ash       Preparation Section of the Guide for removing un-
(Fraxinus spp.), and maple (Acer spp.) drop their seed in   wanted vegetation and preparing the seedbed should
the fall and should be collected immediately after seed     be used when preparing a site for direct seeding of
drop. As a general rule, tree and shrub seeds should be     trees. An additional consideration is that soil should be
planted as soon as possible after collection. The longer    well tilled to a depth of six inches to prepare for plant-

DECEMBER 2008                                                                 5  4 E S TA B L I S H I N G U P L A N D V E G E TAT I O N   45
     ing. This is especially important for walnuts and oaks
     that need to be planted deeper (Oakes 2008).

     Direct seeding of trees and shrubs in upland areas
     is typically done without planting upland forbs and
     grasses, as herbicides are used to remove herbaceous
     plants during establishment to give woody species an
     advantage. Forbs and grasses can be planted later, after
     trees and shrubs are established and can compete with
     herbaceous vegetation.

     Some projects have been conducted by drilling tree
     seeds directly into untreated vegetation and then kill-
                                                                  dimethalin at a rate of three quarts an acre is applied
     ing the vegetation with glyphosate in the spring before
                                                                  between frost out until May 15th (before germination
     tree seeds germinate (Edge 2004). The effectiveness of
                                                                  the first year)(in the southern part of the state) to con-
     this technique will depend on the types of weed pres-
                                                                  trol weedy grasses that establish in upland restorations.
     ent and the effectiveness of the herbicide treatment. As
                                                                  Pendimethalin will not affect many broadleaf species
     with other types of planting, site preparation tech-
                                                                  but can control carpetweed, chickweed, lambsquarters,
     niques that most effectively control weeds will provide
                                                                  and pigweed (Oakes 2008). If trees and shrubs have
     the greatest chance of establishment success.
                                                                  been planted without other ground-layer plantings,
                                                                  grass-specific herbicides can be used to remove weedy
     Following site preparation, walnut, oak, and hickory
                                                                  grasses. Clopyralid herbicides can also be used to
                                     seed should be spread
                                                                  remove most broad-leaf weeds (particularly thistle, bur-
                                     over the entire area
                                                                  dock, and ragweed) without affecting tree and shrub
                                     and disked into the
                                                                  seedlings. Mowing above the height of emerging trees
                                     ground so that the
                                                                  can be effective to prevent weeds from seeding.
                                     majority of the seed
                                     is buried one-inch
                                                                  Boxelder is a common pioneer following direct seeding.
                                     deep. Ash, maple, and
                                                                  Boxeldere may require thinning by clipping and treat-
                                     cherry seed should be
                                                                  ing stumps or basal-treating stems to promote planted
                                     broadcast over the site,
     Figure 5.55                     followed by a light har-
                                                                  species. Some boxelder can be tolerated in a planting
                                                                  as it will help minimize browsing pressure from deer,
     rowing. The seed should ultimately be planted ¼ inch
                                                                  helping the desired species to grow faster (Oakes 2008).
     deep (DNR 1998). Cultipack typically is not necessary
                                                                  If possible, female boxelder should be removed from
     after seeding (Oakes 2008).
                                                                  the project area before site preparation is conducted
                                                                  (Oakes 2008).
     Shrubs can be incorporated into planting but are often
     added in later years after weeds are controlled as herbi-
     cides used for weed control can negatively affect shrub
     seedlings (Oakes 2008).

     When planting seeds to establish trees and shrubs,
     weed control is important during the first two to
     three years. A combination of pre- and post-emergent
     herbicides are often used as well as mowing. Sites are
     commonly treated with pre-emergent herbicide the
     first three seasons to prevent weed germination. These
     herbicides should not be used in aquatic habitats. Pen-

46   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                  M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
                                                                             prevent having to replant later.
 Table 5.15 Upland Tree and Shrub Direct
 Seeding Schedule                                                            Resources
 Previous 1 - 2           Conduct site preparation to remove                 Direct seeding of native hardwood trees, HYPERLINK
 years                    weeds and prepare seedbed.                         “
 Mid October              Plant large seeds (acorns, walnut,                 nance/collectingseed.html
                          hickory) with broadcast seeder                     Direct Seeding of Hardwoods in Wisconsin, Edge, G.
                          or fertilizer spreader followed by                 Minnesota SWCD Tree Handbook, USDA
                          disking 2 inches deep (mechanical
                          seeders that create furrows can also               Link to Appendix 5-B, Upland Tree and Shrub
                          be used, eliminating the need for                  Specifications
                                                                             Link to Appendix 5-C, Restoration Details/Diagrams
 Mid October              Spread lighter seeds (ash, maple,
 after seeding            cherry & shrubs) followed by light
 large seed               harrowing.
                                                                             Bacterial and Mycorrhizal Inoculum
 Year 1: Frost out        Apply Pendimethalin herbicide at 3
 -May 15                  qt. per acre.                                      Overview
                                                                             Mycorrhizae fungi are microorganisms that are natu-
 Year 1: July             Mow or spray grass-specific and
                          clopyralid herbicides as needed.                   rally found in healthy soils. They establish a symbiotic
                                                                             relationship with plants. Mycorrhizae benefit by receiv-
 Year 2: Frost out        Pre-bud swell herbicide application.               ing carbon from plants, while plants benefit by receiv-
 -May 15                                                                     ing increased nutrients and water transport, increased
                                                                             tolerance to heavy metals, and increased disease
 Year 2: June             Mow and/or spray grass-specific                    resistance. Mycorrhizae also improve soil structure and
                          and clopyralid herbicides as                       increase cycling of organic matter. Some upland prairie
                          needed.                                            plants that rely on mycorrhizae include warm season
                                                                             grasses such as big bluestem and Indian grass and forbs
 Year 3: April            Pre-bud swell herbicide application.               such as gray-headed coneflower, purple prairie clover,
                                                                             and round-headed bush clover (Miller 1997). They ap-
 Year 3: June             Mow and/or spray grass-specific                    pear to be beneficial in prairie restorations on severely
                          and clopyralid herbicides as
                                                                             disturbed or nutrient poor soils. Seedlings of bur oak
                                                                             grow much quicker when mycorrhizae are incorporated
 Year 4                   Add understory shrubs and thin
                          boxelder as needed.

 Note: seed collection should occur during the season of site preparation.
 Site preparation and planting strategies may vary depending on site

Influence on Other Strategies
Additional tree and shrub seedlings can be added to
plantings. Upland tree and shrub plantings may require
herbivore control measures to protect them from deer
and rabbits. Upland trees and shrubs will likely require
watering during establishment. Paying attention to wa-                       Figure 5.56
tering needs early on will protect the investment and

DECEMBER 2008                                                                                  5  4 E S TA B L I S H I N G U P L A N D V E G E TAT I O N   47
                             into their root systems. At this     These have proven to be ways of supplying vastly
                             time, reliable sources of mycor-     greater quantities of bacteria when compared to the
                             rhizae are still being developed.    amount supplied with a direct legume seed inocula-
                             Most prairie legumes have            tion, resulting in a greater chance of some rhizobia
                             associated rhizobial bacteria        surviving until the legume seeds germinate. Another
                             that fix atmospheric nitrogen        beneficial strategy is to spread inoculants as a separate
                             for the plants in exchange           operation during the spring after planting, at the time
                             for carbohydrates. Rhizobia          when legume seeds are germinating (from unpublished
                             specific for most of the native      finding by Peter Graham of the University of Minnesota)
                             legumes planted in Minnesota         (Jacobson 2006).
                             have been developed at the
                             University of Minnesota. The         Influence on Other Strategies
                             inoculation of cover crops is
                             being researched. Because            The use of inoculum can give a competitive advantage
                             the cover crops are a greater        to native species, decreasing maintenance needs.
     percentage of the seed mix than the legumes, more
     rhizobia are incorporated into the soil when cover crops     Resources
     are inoculated than when legumes are inoculated.             The Tallgrass Restoration Handbook for Prairies, Savannas, and
     Check with the vendor providing seed mixes to ensure         Woodlands, Packard, S., Mutel, C.F.
     that appropriate bacterial inoculum is included with         Use of mycorrhizal inoculum as a soil amendment during
     legumes (Jacobson 2006).                                     prairie restoration. Tallaksen, HYPERLINK “http://www.hort.agri.
     Bacterial and Mycorrhizal Inoculum                           Link to Appendix 5-B, Bacterial and
                                                                  Mycorrhizal Inoculum
     Typical Strategies
     Mycorrhizal Inoculation - Methods of inoculating
     restoration sites with Mycorrhizae fungi include apply-
                                                                  Stabilizing Upland Soils
     ing inoculated soil into trenches where seeds are later
     dispersed, using seedlings that have been inoculated
     with mycorrhizae, dispersing small pellets which consist
     of a mixture of clay, mycorrhizae, and seed, and broad-
     casting inoculated soil over the restoration site (Tallak-
     sen 1999) or wood chips in the case of forest restoration
     (Jacobson 2006).

     Bacterial Inoculation - Legume seeds or seeds of cover
     crops are inoculated before seeding. To prevent desic-
     cation of the inoculants provided with native seed, do
     not open the packaging until immediately before use.
     Direct inoculation of legume seed prior to seeding has
     not always proven effective, especially if the legume
     seed has not been scarified prior to seeding. This is
     because the rhizobia have a difficult time overwintering     Figure 5.57 Upland Stabilization Strategies
     without their legume host. There are promising results
     from methods of inoculation using winter wheat, clay         Overview
     pellets, or peat granules as a carrier for the inoculants    Stabilizing upland soils either before or after planting
     (Jacobson 2006).                                             is an important consideration in the planning process.
                                                                  Stabilization provides protection and moisture for the
48   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                    M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
planted seeds and also provides some amount of ero-           Mulching – Mulching upland buffer areas is recom-
sion control, which can improve the success of project        mended when both upland and wetland seedings are
efforts to establish vegetation in wetland areas. Many        being completed together. At minimum, a buffer strip
wetland seeds will not germinate if covered by more           with widths from 100 to 200 feet around each wetland
than 1/8th inch of soil. The erosion of soil from upland      area that is seeded should be mulched. Greater widths
buffer areas during the establishment phase of a proj-        should be considered for areas with steeper slopes or
ect is a common reason for failure of these seedings.         more erosive soils. In some situations, it may be advan-
Wetland seed is expensive; efforts to protect wetland         tageous to mulch the entire site including the wetland
plantings by stabilizing upland soils should be consid-       areas. Mulch should be disk anchored to prevent it
ered.                                                         from blowing away. It is very important that mulch
                                                              not be derived from stands of invasive or exotic spe-
The current NPDES General Permit for Minnesota                cies such as reed canary grass. Straw from oats, wheat,
requires that final stabilization of construction areas be    and native grasses can be used for projects. Certified
done within 14 days after the construction activity has       weed free grain straw (Mn/DOT Type 3) mulch is often
temporarily or permanently ceased. For large projects,        recommended for wetland projects. Certified weed free
compliance may require that stabilization methods             mulch bales should have a tag affixed to each bale indi-
such as seeding, mulching or other temporary erosion          cating that it has been certified to be weed free by the
products occur in several stages. It is also important to     Minnesota Crop Improvement Association (MCIA). Be-
consider whether other upland soils on a project site         ware of mulch that is described as “marsh hay”, “pasture
need to be stabilized before or after planting. This likley   hay” or “wild hay” as often times it contains substantial
includes uplands in agricultural settings that have been      amounts of reed canary grass or other undesirable
plowed or tilled as part of site preparation.                 introduced species such as red top (Jacobson 2006).

Equipment/Materials                                           Vegetating Construction Areas – Seed mixes devel-
                                                              oped for construction areas such as embankments,
Cover crops, permanent seed mixes, certified weed free        borrow, and other excavation areas should include a
grain straw (Mn/DOT Type 3), native grass straw, oat          combination of early- and late-developing grasses with
and wheat straw, mulch blowers, crimpers, seed drills,        a cover crop for rapid stabilization. Winter wheat is
mulch tackifiers, temporary erosion control products          generally used as a cover species in the fall while oats
and erosion control blankets. .                               is msot commonly used in the spring and summer. The
                                                              seed mix should include species that will be suitable
Typical Strategies                                            for the range of moisture conditions that are expected.
Seeding Uplands for Stabilization – Temporary cover           This includes wet species along the lower areas of con-
crops or a combination of temporary cover crops and           struction areas and drier species for the upper edge.
permanent mixes can be used to stabilize uplands prior
to wetland plantings being conducted. As wetlanda are         Mixes for construction areas and embankments are
often seeded in the fall, upland seeding can be con-          typically dominated with grasses for their stabilizing
ducted the previous spring or fall to provide enough          characteristics and ability to tolerate periodic mowing.
time for establishment of the buffer area for erosion         Forb species are sometimes added to compete with
control. Similar to wetland plantings, a temporary cover      Canada thistle and other weeds. Non-native cool-
crop can act as mulch if it is clipped and disked before      season grasses have historically been used for many
seeding.                                                      construction area plantings, but many programs now
                                                              require the use of warm and cool-season native species.
Working with Crop/Plant Residue in Upland Soils –             See Chapter 5-6 for information about developing seed
Similar to temporary cover crops, the roots and stems         mixes.
of crops such as corn and soybeans can help stabilize
soils. Corn stubble is sometime harvested before final        Whenever possible, construction and site stabilization
seedbed preparation but some crop residue can be left         work should occur prior to the end of September. For
in place when a no till drill is used for seeding.            construction work completed later in the fall, a decision
                                                              must be made to either dormant seed the site or wait

DECEMBER 2008                                                                   5  4 E S TA B L I S H I N G U P L A N D V E G E TAT I O N   49
     until spring to perform the seeding work.                    Regardless of the seeding method, most grasses need
     Dormant seedings are completed after mid-October             to be installed 1/8th to 1/4 inch deep and packed or
     but before the soil freezes.                                 rolled to ensure good establishment. When broadcast
                                                                  or hydroseedingis used, it is generally recommended
     Seeding construction areas the following spring is           to harrow and then roll the seeding area. If harrowing
     generally preferred over dormant seeding in the fall.        is not possible, rolling may be sufficient to create seed
     Germination rates and success for many grass species         contact with the soil.
     will be higher with spring plantings. Any erosion that
     might have occurred during early spring flooding con-        Upon seeding construction areas, additional site sta-
     ditions can be corrected as the soils are prepared for a     bilization work is typically necessary. Areas needing
     late spring seeding. When planning for spring seeding,       additional protection may include slopes steeper than
     it is recommended that the finished grading work in the      2:1, areas with wave action, ditches, spillways or outlets
     fall be traversed with tracked construction equipment        where scouring may occur. Alternative stabilization
                                                                  methods may include erosion control blanket, wood or
                                                                  fiber mulch, synthetic fiber mulch, hydromulch, hydro-
                                                                  seeding, or any other engineering products for erosion

                                                                  In addition, other strategies that will help control and
                                                                  manage sediment from construction and other dis-
                                                                  turbed areas also need consideration. Such strategies
                                                                  may include the use of silt fence for perimeter control,
                                                                  temporary ditch checks, cofferdams, diversions, and
                                                                  protection around functioning inlets.

                                                                  Maintenance requirements typically vary depending
                                                                  on the type of vegetation being installed. If native
                                                                  grasses are seeded, mowing to 6-8 inches two times the
                                                                  first year and once or twice the second year is recom-
                                                                  mended to minimize weed competition and allow na-
     Figure 5.58                                                  tive vegetation to establish. Spot treatment of invasive
     up and down the embankment slopes to both com-               species is recommended as part of maintenance for all
     pact the soil surface and provide for temporary ero-         construction areas. Re-seeding of construction areas
     sion protection. When appropriate, consider requiring        should also be conducted as needed.
     the implementation of other temporary stabilization
     methods such as mulching or erosion blankets in the          Influence on Other Strategies
     fall. Final seeding and stabilization should occur as soon   The mulching of uplands can aid the establishment of
     as practicable in the spring.                                native species, ultimately suppressing weeds. Mulching
                                                                  uplands can also aid the germination of wetlands by
     If the constructed outlet for the project has water          preventing wetland seed from being covered with sedi-
     level management capabilities, it is recommended to          ment. Upland temporary cover crops can act as mulch,
     keep the wetland in a drawn down condition until all         decreasing the need for additional mulching.
     embankment slopes and other critical areas are fully
     established with vegetation.                                 Resources
     Construction areas can be seeded with broadcast seed-        Section 4 – Engineering Design and Construction
                                                                  Mn/DOT Specification 2575, Controlling Erosion and
     ers or seed drills. Seed drills typically cannot be used
                                                                  Establishing Vegetation,
     on slopes steeper than 3:1, so broadcast or hydroseed-
     ing must be used in these situations.
                                                                  Link to Appendix 5-B, Mulching Uplands Specifica-

50   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                  M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E

 5-5 Establishing Vegetation in Wetlands

                                                                     Wetland Planting Strategies covered in this
                                                                     chapter include:
                                                                        Utilizing Existing Native Seed Banks
                                                                        Broadcast Seeding Wetlands
                                                                        Hydroseeding Wetlands
                                                                        Wetland Containerized Plants
                                                                             and Rootstock
                                                                        Wetland Trees and Shrubs
                                                                        Stabilizing Wetland Soils
                                                                        Peatland Restoration

Figure 5.59
                                                                                                natural colonization are

T   he establishment of vegetation in wetlands requires
    careful consideration of existing site conditions and
an understanding of project goals. When planning for
                                                                                                sometimes unpredictable,
                                                                                                particularly if invasive
                                                                                                species are present in the
the establishment of wetland vegetation, many factors                                           immediate watershed, an
should be considered including project constraints, site                                        increasing number of wet-
preparation strategies planned construction activities,                                         land restoration projects
hydrologic conditions, project sequencing, and project                                          are starting to focus on the
budget.                                                                                         planting of seed and other
                                                                 Figure 5.60
                                                                                                plant materials. Seed and
The plant community being restored or created needs              plants can be a significant project cost so it is important
to be determined as part of developing the vegeta-               that project designers understand the techniques that
tion plan. An assessment of existing site conditions is          will most likely result in successful vegetation establish-
necessary to identify wetland types that once existed            ment. For example, it is important that wetland seed is
and may be appropriate for the planned restoration. For          planted near the soil surface and that seed is not buried
created wetlands, the site assessment will help deter-           by sediment.
mine the suitability of the site for the intended wetland
types. Refer to Section 3 Site Assessment of more                The information about planting strategies in this chapter
information on the assessment needs of a project.                is intended to include practices that have been success-
                                                                 ful for practitioners and will be updated as new infor-
The wetland type that is planned for restoration or cre-         mation is obtained through research and practitioner
ation will influence the selection of seed and/or plant          experience. The following vegetation establishment
species to be introduced to the project. Section 5-6             chapters should be reviewed in conjunction with this
includes a discussion of seed and plant placement.               chapter of the Guide to ensure that all components of
                                                                 a project have been considered and that a complete
Project goals and budget play a significant role in the          planting plan will be developed.
selection of planting strategies for wetlands. Projects
that have limited budgets for plant material often               Site Preparation, Section 5-3
rely on native seedbanks or natural colonization for             Establishing Vegetation in Wetlands, Section 5-5
wetland vegetation establishment. As seedbanks and               Selecting Seed and Plant Materials, Section 5-6

DECEMBER 2008                                                                      5  5 E S TA B L I S H I N G W E T L A N D V E G E TAT I O N   51
     Table 5.16 summarizes wetland planting strategies. It can be beneficial to combine a number of planting
     strategies. For example, aquatic plantings often involve the combination of seed, containerized plants, and
     pre-vegetated mats to ensure establishment success and species diversity. The strategy or combination of
     strategies selected will depend on project goals, budget, available equipment, site conditions, and target plant
     communities. The strategies that will be discussed in this section include utilizing existing native seedbanks,
     broadcast seeding, wetland containerized plants and rootstock, wetland trees and shrubs, stabilizing wetland
     soils and peatland restoration.

      Table 5.16 Comparison of Strategies for Establishing Wetland Vegetation

      Technique                             Use/Considerations                                     Relative Costs

      Utilizing Existing                    Can be a cost-effective method of establishing       Low - Minimal if excavation is not necessary to
      Native Seedbanks                      local ecotype seed. Should not be relied on when expose the seedbank.
                                            diverse plantings are the goal of a project (certain
                                            types of wetland seed do not establish well) Dif-
                                            ficult on sites dominated by invasive species or on
                                            sites with sediment accumulation.
      Managing Hydrology                    An important strategy that promotes the germi-         Low – Requires planning and coordination
                                            nation and survivability of many wetland plant         with project engineers.
      Broadcast Seeding                     The primary technique for planting wetlands as         Medium – Depends on project size, seed
                                            most wetland seed requires light to germinate          source, mix diversity, and individual plant
                                            and should be planted near the soil surface.           species included in mixes.
                                            Requires some seedbed preparation.
      Hydroseeding                          Can be used as an alternative to broadcast             Medium/High – Similar to broadcast seed-
      Wetlands                              seeding of wetlands. Limitations related to ac-        ing; depends on project size, seed source, mix
                                            cessibility of equipment. There are also many          diversity, and individual plant species included
                                            specifications to be followed when hydroseeding        in mixes.
                                            wetland seed to ensure that it results in successful
      Wetland Containerized                 Planted to ensure the establishment of vegetation      High - Varies widely due to the size and type
      Plants and Rootstock                  along the zone of open water where seed may be         of plant material. Some rough costs:
                                            displaced by fluctuating water levels and plants       Plug: $1.75 to $2.10 per plant installed
                                            may have difficulty establishing.                      4” container: $5-$7 per plant installed
                                                                                                   Bare root:$2 to $3 installed
      Wetland Trees and                     Planted when wooded swamps or shrub wetlands           High - Varies greatly depending on the size and
      Shrubs                                are the target plant community due to mitigation       type of plant material.
                                            replacement goals or to improve wildlife habitat       Direct seeding - $650-850 per acre (including
                                            in areas that were historically forested.              site preparation, seed, and seeding).
                                                                                                   Bare root: $3-$15 installed
                                                                                                   Containerized: $25-$100 installed
      Mulching Wetlands                     Recommended after seeding wetlands to stabilize Medium –Depends on the acres to be
                                            soil, retain moisture and provide protection for mulched. 1-ton per acre is recommended for
                                            seedlings. Should not be conducted where water wetlands.
                                            levels will fluctuate and only weed free mulch
                                            should be used. Cover crops can be disked and
                                            used as a mulch.
      Peatland Restoration                  Conducted after harvesting of peat or to mitigate      High - Labor intensive as compared to other
                                            for wetland losses. Requires a site with carefully     restoration techniques, increasing per acre
                                            controlled hydrology and a donor site where            costs.
                                            propagules can be collected.
52   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                                      M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
Utilizing Existing Native Seedbanks

When restoring drained wetlands, a common vegeta-
tion establishment strategy is to utilize the remnant na-
tive seedbank that still might exist within the wetland
substrate. A local source of wetland plants will increase
the diversity and probability of establishing a functional
plant community in the wetland. Supplemental seed-
ings or plantings often become a necessary component
of the vegetation establishment plan. Scraping and
sediment removal may also be necessary to expose the
remnant seedbank.
                                                             Figure 5.61 Vegetation From a Native Seedbank
The viability of the existing remnant seedbank in a
drained wetland is often a function of how long the          foliatum), common bugleweed (Lycopus americanus),
wetland has been drained and in agricultural produc-         marsh milkweed (Asclepias incarnata), Canada blue-joint
tion. If the wetland has been drained for less than 20       grass (Calamagrostis canadensis) and wild mint (Mentha
years, some seeds in the seedbank are probably viable        arvensis).
(Galatowitsch and van der Valk, 1994). Wienhold and
vander Valk (1989) found that less than three wetland        A study conducted in northern Iowa suggests that the
species were present in restored prairie potholes that       remnant seedbank could not fully be relied upon for
were drained for 40-70 years, five to seven species in       the establishment of many sedge and wet meadow
those that were drained for 5-30 years, and more than        species. The study compared ten restored wetlands to
eleven species in wetlands that were never drained.          natural wetlands and found that although the vegeta-
Regardless of the amount of time that a site has been        tion of the emergent zone did not differ significantly
drained and in agricultural production, a test of the        between restored and natural wetlands, there were
remnant seed bank can help determine the re-vegeta-          fewer sedge and wet meadow species along the re-
tion potential of the site. See Appendix 5-G for infor-      stored wetland fringe (Galatowitsch and van der Valk,
mation regarding seedbank testing.                           1996). Galatowitsch and Biederman (1998) also found
                                                             that minimal seed reserves and disproportionately high
During the summer of 1998, an inspection of 78 wet-          abundance of invasives (Typha spp., Phalaris arundina-
lands that were restored and created under the Minne-        cea) may limit the ability of natural wetlands to act as
sota Wetland Banking program was undertaken (Shaw            effective propagule sources for re-vegetation during
1998). A number of species were found to colonize in         restoration. These results suggest that it is beneficial
these wetlands even though these species had not             to plant sedge meadow species into restora-
been included in the seeding mix for these projects.         tions where the remnant native seedbank
Plants that established in the wetlands most likely          is being relied on for vegetation estab-
grew from seeds dispersed from populations in or near        lishment.
the restoration site or were remnant native seeds that
were dormant in the wetland substrate. Wet and sedge         Equipment/Materials
meadow species commonly observed included fox
sedge (Carex vulpinoidea), giant goldenrod (Solidago         Backhoes, Excavators, Plows,
gigantea), red-stem aster (Aster puniceus), swamp            Seeding Equipment, Water
aster (Aster lucidulus), marsh aster (Aster simplex), blue   Control Structures.
vervain (Verbena hastata), and slender rush (Juncus
tenuis). Green bulrush (Scirpus atrovirens), Joe-Pye weed
(Eupatorium maculatum), boneset (Eupatorium per-

DECEMBER 2008                                                                5  5 E S TA B L I S H I N G W E T L A N D V E G E TAT I O N   53
                                                                  being too deep to germinate. While deep plowing may
                                                                  expose and allow some native remnant seed sources
                                                                  to germinate, additional seeding should be planned
                                                                  to supplement this strategy and help ensure success.
                                                                  After plowing, a site should be disked and harrowed to
                                                                  smooth and prepare the seed bed.

                                                                  Influence on Other Strategies
                                                                  In many cases, native seedbanks will not result in a di-
                                                                  verse wetland community. The addition of other species
                                                                  to establish a community best suited to compete with
                                                                  invasive plants. When native seedbanks are relied on
                                                                  for establishment the site should be monitored for the
     Figure 5.56 Sediment Removal                                 establishment of invasive species.

     Typical Strategies
                                                                  Native Vegetation in Restored and Created Wetlands, Its Establish-
     Sediment Removal - The amount of sediment that               ment and Management in Minnesota and the Upper Midwest,
     has covered a wetland can influence the usefulness of        Shaw, D.B.
     a remnant native seedbank for a restoration project. If      Recruitment from the seed bank and the development of emergent
     seeds have been covered by even a few inches of soil,        zonation during a drawdown in a prairie wetland. Welling, C.H.,
     their ability to germinate is doubtful. While the sedi-      Pederson, R.L. and Van der Valk, A.G.
     ment can be scraped away to re-expose the seed, it is        Restoring Prairie Wetlands: An Ecological Approach, Galatowitsch,
     difficult to determine the proper depth to excavate.         S.M., and van der Valk, A.G.
     Compare the cost versus time of scraping the sediment        Effect of water regime and competition on the establishment of a
     to expose the existing seed bank. Successful wetland         native sedge in restored wetlands, Budelsky, R., Galatowitsch, S.
     restoration projects have involved the removal of reed
                                                                  Revegetation Strategies for Northern Temperate Glacial Marshes
     canary grass monotypes through scraping, while at the        and Meadows, Galatowitsch, S., Budelsky, R., Yetka, L.
     same time exposing the underlying seed bank. When
     scraping is conducted, the complete root systems of          Link to Appendix 6-B, Native Seedbank Specifications
     the reed canary grass are removed, allowing for the
     germination of the underlying seed bank. Scraping
     may be costly and permits may be required to excavate        Broadcast Seeding Wetlands
     within a wetland. Additional discussion on this topic
     occurs in Sections 5-3 Site Preparation and in Section
     4-6 Excavations and Shallow Scrapes)

     Deep Plowing - The use of plows to access a buried
     seedbank is a more cost effective strategy than scrap-
     ing, however, it is still considered experimental and
     success rates are uncertain. Similar to excavation, it
     can be difficult to determine the depth of the wetland
     substrate containing the remnant seedbank and even
     more difficult to control plow depths since the sedi-
     ment depths will likely vary throughout the wetland
     basin. An advantage of deep plowing is that it can
     turn the soil so that weed seeds that are currently at or
     near the wetland surface become buried and end up            Figure 5.63 Broadcast Seeding by Hand

54   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                    M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
                     Overview                                  Recently, Gleason (2003) found that 0.5 cm (less
                                                               than 0.25 inches) of sediment reduced wetland seed-
                      Broadcast seeding is the most com-       ling emergence by 91.7 percent and total invertebrate
                      mon method of seeding wetlands           emergence 99.7 percent. Unless the seed is of a spe-
                      because the seed of most wetland         cies that floats, or is of relatively large size, this small
                      species requires light to germinate      amount of sediment has the potential of making a
                      and should not be buried. It is          planting fail. It is very important that both the upland
                      important while broadcast seeding        and wetland soils be stabilized to protect the seeding
                      wetlands to have an even distribu-       of wetland species. See the discussion below under
                      tion of seed to avoid bare areas that    Stabilizing Wetland Soils
                      could establish with weedy species.
                      Higher seeding rates are required        Broadcast seeding should be planned to coincide with
                      with broadcast seeding. It is not rec-   the restoration of hydrology. It is common to conduct
ommended that drill seeders be used to seed wetlands           wetland seeding in the fall or winter before wetland hy-
as they will likely bury seed too deep for germination.        drology will be restored the following spring. Planting
                                                               the previous fall will allow for the use of larger equip-
Equipment/Materials                                            ment before soils become too wet. In areas where there
Broadcast seeding is conducted with Cyclone, Vicon or          will be flowing water or open water after snowmelt, it
other types of mechanical broadcast seeders and by             may be beneficial to conduct seeding in late spring or
hand broadcasting.                                             early summer after hydrology has stabilized. This is par-
                                                               ticularly true along the edge of open water where seed
                                                               is easily displaced prior to it being established.
Typical Strategies
Generally, the smaller the wetland seed, the shallower         Broadcast seeding can be conducted in the spring, fall
it must be sown. Wetland plants have adapted to an             or winter. The following discussion covers the benefits
environment that floods on occasion, so many spe-              and limitations of each season:
cies will float if flooded. Wetland seed mixes should be
broadcast onto the surface rather than using seed drills       Spring Seeding
that are used primarily for upland prairie restorations.
Wetland grasses and other species with larger seeds            Seed can be stratified (breaking of seed coat) in prepa-
may benefit from being harrowed into the soil 1/8-1/4          ration for spring seeding. Most wetland species require
inches deep before smaller wetland seeds are broad-            cold-moist stratification but others require acid washes
cast. Wetland sedges, rushes, grasses, and forbs should        or mechanical scarification (Hoag 2000). If not stratified,
be placed on the soil surface, as they require light to        the seed of many species will sit dormant until the fol-
germinate. A firm seedbed must be prepared before              lowing growing season. The stratification needs of wet-
broadcast seeding to ensure that seed is not buried too        land species can vary greatly but the majority of seeds
deep. When broadcast-seeding, carriers such as cracked         including sedges can be stratified by cold/moist stratifi-
corn, annual grains, or sand can be added to seed mixes        cation for one to two months. Grasses and sedges tend
to make seed dispersal easier and make it easier to see        to establish well when seeded in the spring.
where seed has been spread. Carriers and seed can be
combined in barrels that are closed and rolled over the        Spring seeding is beneficial when fall or winter seed-
ground surface for mixing.                                     ing may lead to the loss of seed. Spring seeding should
                                                               be conducted around mid-May after any germinating
Overlap wetland mixes a few feet with upland mixes as          weeds are controlled and before July when moisture
moisture conditions can be variable. The seed should           levels may decrease in wetlands.
be distributed evenly on the soil surface over the entire
site. The site should be cultipacked after broadcasting
seed to ensure good seed-to-soil contact and to pre-
vent seed from being washed away.

DECEMBER 2008                                                                   5  5 E S TA B L I S H I N G W E T L A N D V E G E TAT I O N   55
     Fall Seeding
     Fall seedings tend to develop differently than spring
     plantings because many forbs and sedges require a
     cold/moist period (over-wintering) before they will
     germinate. This is more often the case with mid-suc-
     cessional and late successional species than with early
     successional species. In wetlands, cool-season grasses,
     sedges, rushes, and bulrushes can germinate in the fall
     and/or early spring and will establish quickly if condi-
     tions are good. Seed of most native species will take
     three to four weeks to germinate under ideal conditions
     (moisture, temperature, night length, and dormancy
     break). They will not usually germinate under drought          Figure 5.64 Winter Seeding
     conditions. When seeded in the fall , seed of native              Conduct a fall glyphosate herbicide application
     species can be lost due to rodents, birds, and flowing           (1 Qt.) or do this application in early spring prior to
     water. Annual grain cover crops such as oats and winter          native emergence (timing is important)
     wheat do not over-winter well if dormant seeded.                  Be ready to seed when conditions are right (have
     Dormant seeded annual rye-grass will over-winter and             seed and equipment ready)
     grow the following spring. It will not perform well if it is
     seeded in late June or early July. Fall seeding should be         Seed late in the winter when sun has a higher angle
     conducted after November 1st in the southern half of             (late Feb./March/early April)
     the state and October 15th in the northern half of the           Pick partly to mostly sunny days with temperatures
     state to ensure that seed does not germinate before              between 20° to 40° F
     winter. In some cases, forbs and sedges are seeded in
     the fall followed in the spring by the seeding of grasses        Seed when there is less than one foot of snow over
     that do not require stratification, to prevent the loss of       most areas.
     grass seed over winter (Jacobson 2006).                          Start work early so that seeding is done by 1:00 pm
                                                                      allowing time for sun to warm seed into the soil.
     Winter Seeding
                                                                      Treat establishing weeds in the wetland as needed.
     Seeding can be conducted in wetland and uplands
     during winter months over snow cover. The natural
     freezing and thawing action helps set the seed firmly in       Influence on Other Strategies
     the soil (eliminating the need for further packing), pre-      In some cases species with larger seeds are broadcast
     paring it for growth in the spring. This technique, often      first and then harrowed to ensure good seed-to-soil
     referred to as frost seeding, should be conducted on           contact. Broadcast seeding of wetlands should ensure
     a previously prepared seedbed. Frost seeding has also          the successful establishment of wetland vegetation,
     been successful on sites where soybeans were recently          decreasing future maintenance needs.
     harvested without additional site preparation. This
     technique is not recommended for areas that will have          Resources
     flowing water during the spring. The following are snow
     seeding guidelines from the Detroit Lakes Wetland              Harvesting, Propagating, and Planting Wetland Plants, Hoag, C,J
     ganagement District (Prairie Restoration Techniques/           Revegetation Practices in a Seasonal Wetland Restoration in Min-
     Tips, Hanson, L. Kahan, S.):                                   nesota, Bohnen, J.L., Galatowitsch, S.M.
                                                                    Spring Peeper Meadow: Revegetation Practices in a Seasonal Wet-
                                                                    land Restoration in Minnesota, Bohnen, J.L., Galatowitsch, S.M.

                                                                    Link to Appendix 5-B, Broadcast Seeding Wetlands

56   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                      M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
Hydroseeding Wetlands                                      Herbaceous species can be in-
                                                           stalled after hydroseeding as long
Overview                                                   as planting doesn’t cause signifi-
                                                           cant disturbance.
Hydroseeding wetlands can be an alternative to broad-
cast seeding. Hydroseeding may be a preferred option       Influence on Other
for situations where hydrology conditions do not allow     Strategies
for the use of broadcast seeding equipment and seed        It is important that hydroseed-
can be directed onto a site with a hydroseeder. There      ing is conducted correctly to ensure the successful
are many specifications that must be followed to ensure    establishment of wetland vegetation to decrease future
that wetland seed is hydroseeded appropriately. Hy-        maintenance needs.
droseeding uses a slurry of seed, chopped mulch, and
sometimes fertilizer. Seeds are often coated with absor-   Resources
bents to give them a better chance of survival during
germination. A high-pressure pump is used to spray         Mn/DOT Specification 2575.3 Hydroseeding,
the slurry onto the prepared soil surface. One common
problem with hydroseeding is ensuring good seed-to-
soil contact. Better contact can be accomplished by        Link to Appendix 5-B, Hydroseeding Wetlands
using a chain drag or harrow and roller after seeding to   Specifications
incorporate seed into the soil.

                                                           Wetland Containerized Plants
                                                           and Rootstock

                                                           Plants are used to establish emergent aquatic vegeta-
                                                           tion in shallow open water, deep marsh, and shallow
                                                           marsh zones where seed can be difficult to establish.
                                                           Plants are also used in sedge/wet meadow and wet
                                                           prairie to establish species that are difficult to grow or
Figure 5.65 Hydroseeding, Photo by Rusty Schmidt           that are unavailable as seed. It is common to plant a
                                                           combination of plants and seed to increase the chance
Equipment/Materials                                        of establishing a diverse plant community.

Hydroseeders, harrows, drags.

Typical Strategies
Hydroseeding can be conducted in spring or fall.
When hydroseeding is conducted, the seedbed must
be loosened to allow spaces for seed to make good
contact with the soil to prevent washing. A fan-type
nozzle should be used with approximately 500 gallons
of water for a visual tracer to ensure uniform coverage.
The seed-water slurry should be applied within one
hour after the seed is added to the hydroseeder tank.
Seed should be dragged or harrowed and then rolled
following hydroseeding if conditions allow. If trees and   Figure 5.66 Planting Along Open Water
shrubs are also being planted, they should be installed
before hydroseeding to prevent seedbed disturbance.

DECEMBER 2008                                                               5  5 E S TA B L I S H I N G W E T L A N D V E G E TAT I O N   57
     Environmental influences such as waves, turbidity,             Due to limited commercial availability of many wetland
     fluctuating water levels, herbivores, and ice heave can        plant species, it is best to check with suppliers well
     influence the survival of aquatic vegetation. There are        in advance of specifying them for a project. Most of
     several options to install live plants including contain-      these plant species will spread vigorously once they are
     erized plants, pre-vegetated mats, transplanted, and           installed. Therefore, clusters or colonies of plants can be
     bare-root material.                                            placed throughout the site and they will expand from
                                                                    there. The number of clusters or colonies of individual
     When using containerized plants and rootstock, it is           species established on a site will vary depending on
     important to ensure that adequate wetland hydrology            the size of the project, but a minimum of three to five is
     will be present to ensure survivability of the plants.         recommended per species.
     After wetland vegetation is planted, the soil must be
     kept consistently moist. Moist soil will also faciliate        Equipment/Materials
     planting by hand. When possible, plant after a rain or
     during a rainy period. If hydrology cannot be managed          Spades, Shovels, Planting Bars, Water Holding Gels,
     or is not yet present in the wetland, it may be necessary      Containerized Plants, Bare Root Plants (Rootstock),
     to utilize overhead irrigation systems, drip irrigation, or    Prevegetated Mats.
     watering trucks during dry periods to help with estab-
     lishment until wetland hydrology is sustainable. Where         Typical Strategies
     watering is impractical, a gel-like substance can be applied   Containerized Plants – Potted plants are used for
     to the roots of the plants before planting to help the plant   establishing emergent species such as bulrushes,
     retain water (Bohnen and Galatowitsch, 1999). Terrasorb        sweet flag, bur-reed, and wild iris that can spread into
     and SoilMoist are two common brand names.                      open water. An increasing number of submergent and
                                                                    floating-leaved species are also becoming available in
     Sites should be assessed when planting into open               containers or as bare-root plants.
     water to ensure that conditions are favorable for plant
     growth. When planting emergent and submergent                  Seedlings that have been established for one to three
     vegetation, it is beneficial to find areas protected from      months in 48-72 cell plug trays are used for re-vegetating
     wind and waves such as protected coves. Water quality          forbs and grasses in situations where wave action or
     is an important consideration when planting submer-            other disturbances will not damage the small plants.
     gent vegetation as sufficient light penetration can            In some cases, coconut fiber logs or similar products
     be important for establishment. Herbivore control to           are used along shorelines to buffer wave energy. Plugs
     prevent grazing by carp, geese, and muskrats can be es-        are staggered along the edge of the water to allow for
     sential for some projects. See Appendix C for herbivore        changing water levels. Larger plants such as two-inch,
     control details.                                               four-inch and gallon containers can have advantages
                                                                    over plugs in that larger plants can handle greater
                                                                    changes in water levels and other disturbance such as
                                                                    wave action. It is common to install containerized plants
                                                                    in early summer after they have had time to sufficiently
                                                                    grow into containers and before the heat of summer.
                                                                    Some research has shown that August and September
                                                                    plantings do not result in high survival rates (Vander-
                                                                    bosch & Galatowitsch, currently unpublished data).
                                                                    Research has also indicated that planting seedlings of
                                                                    Carex such as lake sedge and tussock sedge may result
                                                                    in better survival than planting rhizomes (Budelsky and
                                                                    Galatowitsch 2004).

                                                                    When grown in containers, plants should have roots
     Figure 5.67 Shoreline Planting with Erosion Control,
                                                                    visible at the edge of the root ball when plants are
     Photo by Prairie Restorations , Inc.
                                                                    removed from containers. Roots should be visible when

58   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                    M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
plants are removed from containers. If root masses are        It is best to install pre-vegetated products when the
too small, the plants may have difficulty establishing        water level is relatively stable. Species installed as live
(Garbisch 1994). If potted plants become root bound,          plants in clusters or pre-vegetated mats will spread
cut or tear the root mass before planting to allow the        quickly either from rhizomes or from seed. Therefore,
roots to grow naturally. It is important to pre-order         you don’t need to saturate an entire site with live plants.
plants as early as possible to ensure that appropriate        Mats are typically secured with biodegradable stakes or,
species are available and that there will be sufficient       in standing water, with rocks .
time for them to root into pots. Re-vegetating sites with
herbaceous species that were grown in greenhouses             Bare-Root Plants and Transplants –Transplants are
have been shown to have a higher establishment rate           dug from wild populations while bare-root plants are
than plugs collected from wild populations (Hoag and          grown in production beds with the soil washed off
Sellers 1995).                                                before transport. Transplants of wetland species should
                                                              be collected from well-established beds and, if possible,
If plants are installed without seed, space them 18”          planted the same day. It is not necessary to go deeper
apart for slower- growing species and up to five feet         than five to six inches when digging rootstock; this will
apart for fast-growing species. If seed and plugs are         allow for the collection of sufficient root mass while
installed, the plugs can be spaced further depending          allowing the parent plant enough root mass to grow
on budget and project goals.                                  back. Most rootstocks and bare root plants are collect-
                                                              ed in early May, however there has been success with
Pre-vegetated Mats - Pre-vegetated mats come in a             transplanting as late as mid-July. Rootstocks of aquatic
variety of sizes. An erosion control product is the base
in which the plants are grown. The cost of pre-vegetat-
ed products is typically higher than that of container-
ized plants because of their size, materials and efforts
to grow and transport. Pre-vegetated mats and blan-
kets are useful for stabilizing shorelines, channels, etc.,
where erosion is a concern and rip-rap is not desired.
They are also used for the establishment of emergent
vegetation in wetlands where hydrology has already
been restored or created. Pre-vegetated products need
to be pre-grown for a minimum of five weeks dur-
ing the spring and early summer to ensure that the
seedlings get established before installation. If ad-
equate time is not provided, there is a risk that slower-     Figure 5.69 Spreading Masses of Emergent Plants
germinating species will drown if they are inundated
too early in their life stage. It is important to pre-order   species should not be collected in areas where invasive
pre-vegetated mats to ensure availability.                    species such as purple loosestrife are present. In nurser-
                                                              ies, it is common to wash soil off of roots to minimize
                                                              the transport of invasive species seed and decrease
                                                              shipping costs. The removal of soil works best early
                                                              in the spring when temperatures are cool, decreasing
                                                              plant stress.

                                                              It is important to keep roots of bare-root plants and
                                                              transplants moist during the planting process and to
                                                              set them firmly into the ground. A tree-planting bar
                                                              or tile spade can be used to plant propagules above
                                                              ground and underwater. Plant at a depth so that the
                                                              previous soil line on the plant matches the new soil line
Figure 5.68 Pre-vegetated Mat                                 (Hammer 1992).

DECEMBER 2008                                                                  5  5 E S TA B L I S H I N G W E T L A N D V E G E TAT I O N   59
     Wetland plugs will spread about 9 to 12 inches in a
     growing season. Plants should be spaced according to
     the growth rate of the plants. For example, river bul-
     rush, which grows quickly, should be spaced four to five
     feet apart while the slower-growing hard stem bulrush
     should be planted two feet apart (Galatowitsch and
     van der Valk, 1994). Plants can be installed from April
     through late October as long as there is sufficient water
     (Hoag, 2000) but early season planting may be most
     successful. It helps to cut off half of the above-ground
     growth with pruners if planted during warm weather.

     Plants, except for water lilies, arrowhead, and pickerel     Figure 5.70 Narrow-leaf Cattail
     weed, must be planted with their tops out of the water
     or they will not survive. The zone where emergent spe-
     cies are planted ranges from areas with saturated soils
     to areas having several feet of water. Some species pre-
     fer saturated soils for establishment but can later grow
     in deep water; an example is pickerel weed. Bulrushes
     will grow in both deep and shallow water. Hardstem
     bulrush prefers calcium rich substrates while softstem
     bulrush and river bulrush is tolerant of a broader range
     of conditions (Shuttleworth, 1999). Most sedges prefer
     shallow water and saturated soils. If a project goal is
     to establish food for waterfowl, plans should include
     planting of species such as wild rice, duckweed, ar-
     rowhead (or duck potato), wild celery, sago pondweed,
     and bur-reed. These species are used by both diver and
                                                                  Figure 5.71 Floating-leaved Pondweed
     puddle ducks (Jacobson, 2006).
                                                                  Protecting New Plantings
     Cattails are generally not planted into restored wet-
     lands. Although broad leaf cattail (Typha latifolia) is      Enclosures of wire may be necessary to protect new
     a desirable native emergent species, it tends to out-        plantings from rough fish or muskrats. The enclosure
     compete other emergent species in restored wetlands.         should be about six feet wide and 12 feet long and
     Hybrid cattail (Typha glauca) is invasive and can ag-        should be covered (often with flagging tape) to keep
     gressively colonize and dominate restored and created        wildfowl out while the plants are becoming established.
     wetlands. Cattail seed is dispersed widely by wind and       Such enclosures are needed for a variety of wetland
     germinates easily on moist soil. Cattails can rapidly        plant types in order to exclude herbivores such as geese
     vegetate a wetland and, once established, their dense        (Galatowitsch and van der Valk, 1994). Seed Appendix
     leaves and dead plant litter can prevent other emer-         5-C for herbivore protection details.
     gents from growing. Techniques for removing cattails
     are discussed in Appendix 5-A.                               In areas where there is significant wave action, wave-
                                                                  breaking devices may be needed to protect plantings
     Submergent plants can be established as live plants or       of submergents. These devices can be constructed of
     tubers. It is recommended that four to six species (mini-    coconut-fiber logs, willow bundles, hardwood brush,
     mum) be installed, and more if possible. Submersed           rock within filter fabric, plywood, or double layers of
     aquatics should be planted in sheltered areas under          plastic fence. These materials may need to be anchored
     two to four inches of water. Mats of algae should be         with stakes, depending on how buoyant and moveable
     removed to allow sunlight to reach the plants.               they are (Henderson et al. 1999). A University of Min-
                                                                  nesota Extension publication, Shoreland Landscaping

60   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                  M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
Table 5.16 and 5.17 summarizes planting strategies for some of the more common emergent and submergent species:

 Table 5.17 Planting Strategies for Emergent Species
 Wild Rice                   An an annual plant typically established from seed. Seed is stored in a submerged condition from
 (Zizania aquatica)          harvesting up until being sown into the water. Optimum water depth for wild rice ranges from 12
                             to 18 inches deep. Seed can be harvested from public waters with a DNR license purchased at DNR
                             license vendors. Wild rice naturally occurs north of the Minnesota River and east of the Red River
                             Valley in Minnesota. It may be difficult to establish and maintain outside of its natural range.

 Softstem Bulrush            Can be grown from containerized plants in early spring to mid-summer in sand to muck soils. Soft-
 (Schoenoplectus             stem bulrush is susceptible to herbivory by muskrat (Smart et al. 2005).

 Arrowhead                   A staple waterfowl food. It can readily be established from seed from quite a few sources. It can also
 (Sagitttaria latifolia)     be established by planting tubers or from nursery raised plugs. If started from seed, seed must be
 (also known as “Duck        sown in moist soil at the water’s edge for best results. There are several closely related species of
 Potato”)                    arrowhead that provide suitable food value.

 Wild Celery                 Established by planting tubers (root segments) taken from live plants. They are planted in 1 to 5
 (Vallisneria americana)     feet of water, provided the water is clear enough that sun penetrates to the depth planted. These
 And                         plants could also be started using pre-vegetated mats, the tubers are encased in clay balls and
 Sago Pondweed               planted at 1 to 2 foot spacing. Very few vendors market wild celery and sago pondweed tubers
 (Potomogetan pectinatus)    and even fewer sell the seed. The seed should be sown in the fall using fresh seed lightly pressed
                             into the substrate. Plants can be harvested from public waters only under a permit granted by the
                             Minnesota Department of Natural Resources, Division of Ecological Services. Care must be taken to
                             not harvest and spread such plants as Eurasian Milfoil if harvesting the tubers yourself (Moore and
                             Jarvis 2007).

 Giant Bur-Reed              Provides food for waterfowl and muskrats as well as excellent cover for duck broods. Tolerant to
 (Sparganium eurycarpum)     grazing by muskrats and pollution once established and will compete favorably with cattails and
                             reed canary grass. It can establish from seed, tubers or from nursery-raised plugs. It is reported that
                             the seed has to go through dormancy twice before it will germinate reliably

 Table 5.18 Planting Strategies for Submergent and Floating Leaved Species
 Duckweed                    Established by transplanting live plants that can be seined from existing populations.
 (Lemna minor and
 Spirodela polyrhiza)
 (also known as
 “Duck Meat”)

 White Water Lily            Grown from containers or bare root in early spring to mid-summer in sand to muck soils (Smart et
 (Nymphaea odorata)          al. 2005).

 Illinois Pondweed           Grown from containers or bare root in early spring to mid-summer (Smart et al. 2005).
 (Potamogeton illinoensis)

 American Pondweed           Grown from containers or bare root material in early spring, or from cutting from spring to mid-
 (Potamogeton nodosus)       summer (Smart et al. 2005).

 Water Stargras              Grown from containerized plants in early spring to mid-summer (Smart et al. 2005).
 (Heteranthera duia)

DECEMBER 2008                                                                          5  5 E S TA B L I S H I N G W E T L A N D V E G E TAT I O N   61
                                                                       Link to Appendix 5-B, Containerized Plants and
                                                                       Rootstock Specifications

                                                                       Link to Appendix 5-C, Restoration Details/Diagrams

                                                                       Wetland Trees and Shrubs

                                                                       Wetland trees and shrubs are typically planted when
                                                                       wooded swamps and shrub wetlands are a goal for a
                                                                       wetland project. Planting trees and shrubs in wetlands
     Figure 5.72 Fencing to Exclude Geese                              is still a relatively new science and more information
                                                                       will improve survival and growth rates. Some estimates
     Series, A Guide to Natural Landscaping and Revegetation           show that it may take 35-50 years before restored or
     for Enhancing Lake Quality, includes building plans for           created forested wetland sites have wetland vegetation
     constructing a wave-break structure. The wave-break               and wildlife similar to mature forested wetlands due to
     structure in the Guide is constructed out of PVC pipe.            plant mortality and slow growth rates of nursery stock
     The structure is recommended for sites with low wave              (Perry et. al.). The rate of establishment will depend on
     impacts. Structures made out of rock, steel, or wood              the restoration strategy and size of plant materials used
     may be necessary for sites with greater potential for             and the amount of maintenance. Planting strategies
     wave action.                                                      chosen for a project often depend on the type of com-
                                                                       munity to be restored, project goals, and budget.
     Influence on Other Strategies
     The use of containerized plants and rootstocks may in-
     fluence the maintenance strategies that are selected for          Tree Planting Bars, Spades, Shovels, Augers, Tractor
     a project. In cases where only containerized plants are           Pulled Planters, Containerized Trees and Shrubs, Bare
     used (without seed), sites can be flooded early in estab-         Root Trees and Shrubs, Cuttings, Tree and Shrub Seed.
     lishment to suppress weed germination and establish-
     ment. Careful control of water levels is important while          Typical Strategies
     seedlings are establishing. When seed and container-
     ized plants/rootstock are used together, spot treatment           The ground layer, shrub layer, and canopy layer should
     of weeds and mowing will still be primary strategies to           receive equal consideration during the planning for
     control invading weeds.                                           shrub and forested wetlands. Seed of herbaceous
                                                                       plants along with tree and shrub seed is typically
                                                                       planted first into a shrub or forested wetland restora-
                                                                       tion. Bare root and containerized shrub and tree
     Harvesting, Propagating, and Planting Wetland Plants, Hoag, C,J   species are planted into areas where seed has already
     Revegetation Practices in a Seasonal Wetland Restoration in       been installed.
     Minnesota, Bohnen, J.L., Galatowitsch, S.M.
     Update to the Propagation and Establishment of Aquatic Plants     Planting bare root trees in soils that stay saturated for
     Handbook, Smart, R.M., Dick, G.O., Snow, J., R.                   most of the year is not recommended, as too many
                                                                       fibrous roots are lost during transplanting; the trees will
     Wild Rice Seeding Guidelines (644), NRCS Biology Jobsheet #14
     Shoreline Erosion Control        die before the fibrous roots grow back (Garbisch, 1994).
     terway/erosioncontrol.html                                        Studies by McIninch, (1994) have shown that
                                                                       wetland woody species grown in mesic conditions are
     Spring Peeper Meadow: Revegetation Practices in a Seasonal Wet-
     land Restoration in Minnesota, Bohnen, J.L., Galatowitsch, S.M.   more adaptable to wetlands than plants grown under
                                                                       saturated or partially saturated conditions. Ultimately,

62   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                       M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
                                                            The goal of most forest and shrub wetland projects is to
                                                            obtain a stem density similar to a natural community.
                                                            In some cases, trees and shrubs are planted at higher
                                                            densities than is found in natural communities to create
                                                            greater competition for weeds. In this strategy, trees
                                                            and shrubs are sometimes planted ten feet apart. This
                                                            strategy will increase initial costs but may decrease
                                                            maintenance needs.

                                                              Table 5.19
                                                              Trees & Shrubs For A Forested Wetland

                                                              Common             Botanical                   Installation level
                                                              Name               Name                        above water table

                                                              Red maple          Acer rubrum                 2-3 feet

                                                              Tamarack           Larix larcina               1-2 feet

                                                              Black ash          Fraxinus nigra              1-2 feet

                                                              Speckled           Alnus rugosa                0-1 foot

                                                              Red osier          Cornus sericea              1-2 feet
Figure 5.73 Containerized Wetland Shrubs                      dogwood

it is important to pay attention to hydrology when            American           Ribes america-              1-2 feet
planning tree and shrub plantings. Some species such          black currant      num
as tamarack can benefit from being planted on mounds
within wetlands. Natural forested wetlands have vary-         Meadow-            Spiraea alba                1-2 feet
ing elevation changes that have developed from fallen
trees, root masses, animal activity, and frost heave that
support a wide variety of plant species. Working to cre-
ate microclimates within forested wetlands may help         Planting Wetland Tree and Shrub Seed
increase survival rates and species diversity.              Typically, tree and shrub seed is seeded along with
                                                            wetland grasses, forbs, and sedges. The advantage of
Soil compaction can prevent tree and shrub root             seeding trees and shrubs is that it can be relatively inex-
growth. Heavy equipment should be used only on dry          pensive and high densities of seedling trees and shrubs
soils; frost rippers may be beneficial on some sites to     can decrease mortality from deer and rabbits. It can
break up compaction.                                        take a while for trees and shrubs to establish from seed,
                                                            so it is common to plant bare root and containerized
Soil tests can help determine if soils need amendments      plants in addition to seed.
such as compost or slow release fertilizer and if the
pH is within target ranges, between 4.5 to 6.5 for most
communities. It is often impractical to amend soil over
large acreages, so soil is often amended as trees and
shrubs are planted by mixing compost or other amend-
ments into the planting holes.

DECEMBER 2008                                                                 5  5 E S TA B L I S H I N G W E T L A N D V E G E TAT I O N   63
                                                 Installing Tree and   to make holes in the soil using metal re-rod to prevent
                                                 Shrub Cuttings        the loss of buds as cuttings are installed. One-half to
                                                                       two-thirds of the cutting should be placed in the soil
                                     In spring, certain species        depending on the length of the cutting. Typically, cut-
                                     of trees and shrubs can           tings are installed one to two feet into the ground. It is
                                     be grown from cuttings.           important that the soil remains moist until the cuttings
                                     They include nannyberry,          have developed a root system.
                                     red osier dogwood, wil-
                                     lows, cottonwoods, alder,
                                                                       Planting Bare Root Wetland Trees and Shrubs
                                     and poplars. Collection
                                     should occur in late              Bare root trees and shrubs come in a wide range of sizes
                                     winter or early spring, a         from six-inch tall seedlings to ten-foot tall trees. Seed-
     Figure 5.74 Mixing Tree         few weeks prior to bud            lings are the most common type of bare root material
     and Shrub Seed                  burst for spring plantings.       planted in wetland projects. Generally, 100 to 500 bare
                                     For fall plantings, cuttings      root trees/shrubs are planted per acre depending on
     should be collected around the time that most leaves              the wetland type to be restored and the size of material
     have fallen off. Cuttings should be 1½ to 4 feet long             installed. Trees and shrubs are often planted in clusters,
     and ½ to 2 inches in diameter and from relatively young           where a cluster consists of 5 individuals of a species
     trees/shrubs. There has also been success with planting           spaced evenly around the perimeter of a circle with
     larger diameter, pole size cuttings of willow and cot-            a diameter of approximately 20 feet. Clusters of indi-
     tonwood installed in existing reed canary grass stands            vidual species should be spread randomly over the site
     (Antieau, C., 2006).                                              in the appropriate area for each species being planted.
                                                                       Areas are determined by site hydrology and light
     Cutting should be stored above zero degrees F. Cuttings           conditions. Clusters of different species may overlap.
     can be refrigerated between 31 to 40 degrees F and 60             Unless the site already is saturated, the trees and shrubs
     to 70 percent humidity. Frozen cuttings can be stored             should be watered at the time of planting.
     with snow to reduce drying. Cuttings can be stored
     over winter if necessary. Cuttings should be monitored
     for drying, sprouting, or mold (Alaska Dept. of Fish and          Planting Containerized and Ball and Burlap
     Game 2005).                                                       Wetland Trees and Shrubs

     Cuttings can be                                                   Containerized trees and shrubs can vary greatly in size
     placed in moist                                                   from one gallon containers to 25 gallon trees. Large
     sand or water to                                                  plants can also be obtained as balled-and-burlapped
     keep them cool                                                    material. Cost is a limiting factor in the use of container-
     and hydrated                                                      ized and ball-and-burlap material. Containerized mate-
     before planting.                                                  rial tend to have higher survival rates than bare root
     The plantings can                                                 trees and shrubs. Holes dug for containerized plants
     be soaked for 24 to                                               should be 2.5 times the diameter of the container. This
     48 hours (not more                                                will ensure that the roots will have room to grow. It is
     than four days)                                                   most important that the hole
     before planting to                                                is the widest near the surface
     improve survivabil-                                               where fibrous roots will grow. It
     ity (Alaska Dept.                                                 is also beneficial to scarify the
                            Figure 5.75                                edges of the hole to create a
     of Fish and Game
     2005). Planting should occur shortly after the ground             transition from the undisturbed
     thaws. Planting can occur as late as July 1 if conditions         soil to the backfill soil. The adage,
     are favorable. Plant cuttings into saturated soil three           “give a $10 tree a $100 hole”
     to ten feet apart depending on the eventual size of               provides a good understanding
     the species (around 10-15 feet is a sufficient spacing            of how important a properly dug
     for most shrubs in a restoration). It is recommended              hole is for tree growth.

64   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                       M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
                                                                  Ensure the root collar of trees and shrubs is within
                                                                  one inch of the surface.
                                                                  Roughen the sides and bottom of the planting hole
                                                                  with a shovel.
                                                                  Loosen roots on the edge of containers and
                                                                  spread-out roots of bare root material.
                                                                  If the planting hole is not already saturated, add
                                                                  water, backfill half of the hole, add more water, and
                                                                  then add remaining soil.
                                                                  Lightly tamp the soil surface.
                                                                   Add mulch if possible to retain moisture and
                                                                  inhibit weeds.

                                                                Protecting Trees and Shrubs
                                                                Wetland trees such as white
                                                                cedar that are extremely
                                                                vulnerable to deer browsing
                                                                and need protection. 14-gauge
                                                                wire with 2x4 inch openings
                                                                can be used to create four-foot
                                                                diameter by five-foot tall deer
                                                                exclosures. Fencing of this size
Figure 5.76
                                                                does not require posts as the
                                                                base can be buried in soil or
Proper planting depth is very important with container-
                                                                woody debris (Wagner 2007).      Figure 5.77 Wire
ized plants. The “root flair”, or point where the roots flare                                    Fencing Around Trees
out, should be no more than one inch below the sur-
                                                                Bud caps can also be used to deter deer for some spe-
face after planting. Deeper placement can lead to roots
                                                                cies. They are particularly important for seedling white
that grow in a circular manner around the tree, causing
                                                                pine but can also protect deciduous trees and shrubs.
tipping and constriction of the stem.
                                                                Wire screening can be placed around tree and shrub
                                                                stems to prevent girdling from rodents.
Guidelines for planting containerized and bare-root
wetland trees and shrubs in wetland restoration sites
                                                                Follow-up watering is important for establishing trees
                                                                and shrubs. If soils are not saturated, plantings should
  Plant on a day with low wind and cool temperatures            be receiving approximately one inch per week at a
  and before a rain if possible.                                minimum through rainfall or watering.
  Keep roots moist and protected during transport
  and planting.                                                 Influence on Other Strategies
  Dig planting holes at least twice the diameter of the         When trees and shrubs are used in wetland plantings,
  root mass.                                                    care should be taken to ensure that spot treating of
  If trees and shrubs will be planted in a mound, the           weeds and mowing do not eliminate seedlings from a
  excavation should occur before any seeding or other           site. Large buckets can be placed over seedlings for pro-
  planting occurs.                                              tection when conducting herbicide application. Trees
                                                                and shrubs will require protection from deer in the form
  When planting seedlings with spades or dibble bars,           of bud caps or exclosures; hoever, this is not practical
  make holes large enough to accommodate spread-                for very large sites where large numbers of seedlings
  out root masses.                                              have been planted.

DECEMBER 2008                                                                   5  5 E S TA B L I S H I N G W E T L A N D V E G E TAT I O N   65
     Restoration and Creation of Forested Wetlands: A Guide,
     Palmintier, C., Appleton, B.
     Revegetation Practices in a Seasonal Wetland Restoration in
     Minnesota, Bohnen, J.L., Galatowitsch, S.M.
     Minnesota SWCD Tree Handbook, USDA

     Link to Appendix 5-B, Wetland Tree and Shrub

     Link to Appendix 5-C, Restoration Details/Diagrams            Figure 5.78 Establishing Wetland Vegetation

                                                                   Mulching – Mulching helps stabilize soil, hold seed in
     Stabilizing Wetland Soils                                     place, and retain moisture for germination. Mulch is ap-
                                                                   plied at a rate that can hold soil but still allow sunlight
                                                                   to reach the soil surface. Mulch needs to be disc-
                                                                   anchored to ensure that it does not blow away. Rising
     Stabilizing wetland soils either before or after planting     water levels can cause mulch to float and accumulate
     is an important consideration in the planning pro-            along shorelines, requiring removal.
     cess for the project. Stabilization provides protection
     and moisture for the planted seeds and also provides
     some amount of erosion control which can improve
     the success of project efforts to establish vegetation in
     wetland areas. Many wetland seeds will not germinate
     if covered by more than ¼ inch of soil and the erosion
     of soil from surrounding areas during the establishment
     phase of a project is a common reason for failure of
     these seedings. Wetland seed is expensive and efforts
     to protect wetland plantings by stabilizing the soils         Figure 5.79 Mulching with Straw, Photo by Natural
     should be considered.                                         Resources Research Institute

     Equipment/Materials                                           The recommended mulching rate in wetlands is one to
                                                                   two tons per acre. It is very important that mulch not be
     Temporary cover crop, mechanical mulchers, agricul-           derived from stands of invasive exotic species such as
     tural straw, prairie grass straw, anchoring disks.            reed canary grass. Certified weed-free grain straw (Mn/
                                                                   DOT Type 3) mulch is recommended. Certified weed
     Typical Strategies                                            free mulch bales should have a tag affixed to each bale
                                                                   indicating that it has been certified to be weed free by
     Stabilizing Upland Soils - Temporary cover crops that
                                                                   the Minnesota Crop Improvement Association (MCIA).
     are lightly disked can act as a mulch and have the add-
                                                                   Beware of mulch that is described as “marsh hay”,
     ed benefit of being rooted into the soil. A temporary
                                                                   “pasture hay,” or “wild hay” as it often times contains
     cover crop can be used as mulch if it is clipped and then
                                                                   substantial amounts of reed canary grass.
     disked before seeding. The use of a temporary cover
     has the added benefit of being rooted and less prone
                                                                   It is recommended that water levels be managed below
     to floating. Costs of planting temporary cover crops
                                                                   the planting zone until the seedlings are 6 to 12 inches
     and mulching are comparable. Common cover crops
                                                                   high. Then water levels gradually are raised. If flooding
     include oats, spring wheat winter wheat, ReGreen, fowl
                                                                   occurs, un-crimped straw mulch will float and drift into
     bluegrass and slough grass.
                                                                   windrows. If this occurs, these windrows will need to be
                                                                   removed to allow seed under the drift lines to germinate.

66   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                   M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
Influence on Other Strategies                                 nutrient conditions. Vegetation on bogs and poor fens
                                                              is dominated by Sphagnum and Polytrichum mosses,
It is important that mulch used in wetlands not contain       cottongrass, and low growing shrubs such as Labrador
weed seeds as this may result in additional mainte-           tea, leatherleaf, bog rosemary, and bog laurel. Black
nance needs. Temporary cover crops can act as mulch,          spruce and tamarack commonly occur on forested
eliminating the need for additional mulching.                 bogs. Rich fens have conditions such as higher pH and
                                                              nutrient availability that favor the growth of a more
Resources                                                     diverse assemblage of wetland plants. Peatlands are
Restoring and Managing Native Wetland & Upland Vegetation,    found primarily in the boreal forest biome, which has
Jacobson, R.                                                  cool temperatures and short summers. The cool, wet   climate in combination with poor drainage allows for
                                                              the formation of peat.
Link to Appendix 5-B, Mulching Wetlands Specs
                                                              Reliable, large-scale restoration techniques for in-kind
                                                              restoration of Sphagnum dominated bogs have been
Peatland Restoration                                          developed at Laval University in Quebec and are de-
Contributions from Kurt Johnson, University of Minnesota      scribed in the publication “Peatland Restoration Guide
Duluth Natural Resources Research Institute                   Second Edition” (Quinty and Rochefort, 2003). Similar
                                                              research has been conducted in Minnesota with good
Overview                                                      results (Johnson, et al. 2000). These techniques are con-
                                                              sidered state-of-the-art for North America for restoring
The restoration of peatland is conducted in locations
                                                              a Sphagnum-dominated Type 8 wetland once peat
where peat has been mined or in sites where condi-
                                                              mining is completed.
tions are suitable for Sphagnum mosses and associated
peatland plants to establish.
                                                              This restoration method is based on research conduct-
                                                              ed to date on the restoration of Sphagnum dominated
Equipment/Materials                                           peatlands. The potential has been demonstrated for
                                                              re-establishing native vegetation on harvested or
Equipment needed to conduct large-scale peatland
                                                              disturbed sites by spreading moss and other plant
restoration includes: 1) an agricultural tractor, prefer-
                                                              fragments collected from natural, undisturbed, “donor”
ably with high flotation tires and four wheel drive, 2) a
                                                              sites, on bare peatland surfaces (Elling and Knigh-
tractor mounted rotovator, 3) a front-end loader, 4) an
                                                              ton,1984; Poschold and Pfadenhauer, 1989; Rochefort,
agricultural manure spreader, and 5) a bale processor/
                                                              et al. 1995, Campeau and Rochefort, 1996). This encour-
forage blower. A grader or peat profiler and a backhoe
                                                              ages the primarily vegetative reproduction of Sphag-
may be needed to level the surface and block ditches
                                                              num (Darlington, 1964; Cronberg, 1993) and allows
on previously mined sites. Materials required include a
                                                              associated peatland plant establishment from seeds,
suitable donor site where Sphagnum moss and associ-
                                                              rhizomes, and other plant structures included with the
ated peatland plant materials can be collected, and
                                                              donor vegetation.
weed free straw to be used as mulch. On some sites, the
addition of rock phosphorus fertilizer may help with
                                                              The first step in any successful peatland restoration
moss establishment.
                                                              project is a thorough evaluation of the mined site
                                                              including remaining peat thickness and chemistry, hy-
Typical Strategies                                            drology, and proximity to a suitable donor area. In order
Peatlands have water-saturated soils that are composed        to re-establish Sphagnum-moss-dominated vegetation,
of partly decayed remains of plants. The plant material       a layer of acid, nutrient-poor peat, at least six inches
accumulates as a result of slowed bacteria and fun-           thick overlying 12 inches of sedge peat should remain
gal action in the waterlogged environment. Different          over the underlying mineral layer. The site must also be
classifications of peatlands include non-forested bogs,       situated such that hydrology can be restored resulting
forested bogs, rich fens, and poor fens (Tester 1995).        in an increase in water level to provide moist conditions
Bogs and poor fens are characterized by acidic, low           necessary for Sphagnum survival and growth. During

DECEMBER 2008                                                                 5  5 E S TA B L I S H I N G W E T L A N D V E G E TAT I O N   67
                           peatland restorations, an existing       This work is best done during the fall prior to planned
                           area of natural undisturbed bog is       vegetation establishment. For intensively drained
                           used as a “donor site” for collect-      mined peatland areas, substantial dams and diking are
                           ing Sphagnum to be spread on             necessary to restore the site’s hydrology. Field ditches
                           the mined area (Quinty and Hood          in mined areas should be blocked at numerous loca-
                           1998). Theshould be set aside            tions (depending upon the surface gradient) to ensure
                           reasonably close to the site, at least   that water is distributed evenly and that the mine site
     one-tenth the size of the proposed restoration. Enrich-        will be subjected to the natural peat accumulation
     ment of the proposed restoration site by high nutrient         and restoration processes. Ditches are usually blocked
     water, the mineral substrate, or peat other than Sphag-        with a backhoe using highly decomposed peat with
     num moss peat can result in colonization by undesir-           low hydraulic conductivity to insure optimum water
     able plant species. If any of these factors are present, it    retention. Ditches should be blocked only after all other
     may be best to follow a different restoration strategy.        restoration activities are completed to allow for equip-
                                                                    ment operation.
     A critical step in restoring acid peatlands involves
     restoring wetland hydrology to the site. Saturated soil is     When a suitable donor site has been selected, the
     essential for the reestablishment of Sphagnum mosses           bog surface must be chopped to provide moss frag-
     that are the primary plant species in acid peatlands           ments for restoration. This is best done in early spring
     (MCA 1999). Ideally, the water table should be restored        (March or April) of the planned restoration year using a
     to a level at or near the peat surface by blocking drain-      tractor-mounted rotovator. Timing for this operation is
     age ditches or using other water management tech-              critical, as the bog surface should be free of snow, but
     niques. Rochefort et al. (1997) found that in greenhouse       there needs to be sufficient frost to support equip-
     conditions, Sphagnum species regenerated most                  ment (Quinty and Hood 1998). These conditions being
     rapidly when water levels were maintained at 0.2 inches        met, the rotovator should be set to chop the top 10 cm
     below the peat. Other studies have found that the              of surface vegetation. The Sphagnum moss from the
     water table must be within 40 cm of the peat surface in        upper layer will have a greater regenerative capacity
     order for satisfactory Sphagnum regeneration to occur          than moss from deeper layers. Several passes may be
     (Schouwenaars, 1988).                                          required to break up frozen pieces. The moss fragments
                                                                    are then loaded onto wagons or a manure spreader
                                                                    using a front end loader and transported to the restora-
                                                                    tion site. The shredded material should not be left on
                                                                    the borrow site as it will quickly dry. The materials can
                                                                    be kept for a few days in a pile at the restoration site
                                                                    (Quinty and Rochefort, 1997). Donor sites will regener-
                                                                    ate in three to five years allowing several collections
                                                                    and resulting in no-net-loss of peatland vegetation.

                                                                    The moss fragments are spread on the bare peat
                                                                    surface of the restoration area using an agricultural ma-
                                                                    nure spreader. Sphagnum should be spread at a ratio of
     Figure 5.80 Establishing peatland species
                                                                    1:10 or one square foot of donor area to ten square feet
                                                                    of bare peat surface (Quinty and Rochefort, 2003). This
                                                                    should result in a layer 1 to 2 cm thick to completely
     Modifying the production field topography to create a          cover the bare peat (Quinty & Rochefort 1997). Get
     level or slightly concave surface has been shown to in-        uniform coverage at the proper ratio by adjusting the
     crease water availability and restoration success. Fields      tractor speed and manure spreader application rate.
     that have a crowned surface after harvesting should            Spreading is best done immediately after plant chop-
     be flattened using a grader or peat profiler to ensure         ping when there is still sufficient frost in the fields to
     a better distribution of water (Quinty and Hood 1998).         support equipment.

68   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                    M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
                                                              Table 5.20
                                                              Typical Schedule for Peatland Restoration

                                                              Year 1, Fall       Site preparation.

                                                              Year 1, Fall       Initial restoration of hydrology and level-
                                                                                 ing of surface.

                                                              Year 2, March      Collection from donor site and spreading
                                                                                 on restoration site.

                                                              Year 2, April      Application of weed-free straw.
Figure 5.80 Spreading Moss Fraqments
                                                              Year 2, April      Application of phosphorus fertilizer.
Covering the reintroduced plant fragments is one of
                                                              Year 2, May        Final restoration of hydrology (ditch
the most important steps in peatland re-vegetation.
Mulch provides humid conditions that are necessary
for plant establishment. Studies have shown that the          Year 2 , May–      Spot treatment of weeds with glyphosate
use of straw mulch overwhelmingly improves Sphag-             September          herbicide. Application of grass specific
num moss establishment and survival (Quinty, 1996;                               herbicide in areas where reed canary
Johnson, et al. 2000). Straw mulch has been successful                           grass is establishing and there is no open
for peatland restorations and is effectively applied to
sites with a forage blower at a rate of 3000 kg per ha or
                                                              Year 3-5, May–     Spot treatment of weeds with glyphosate
1.5 tons/acre (approximately two to three large round         September          herbicide. Application of grass specific
bales or 80 small square bales per acre) (Rochefort                       herbicide in areas where reed canary
2001) (Quinty and Hood 1998). Shrubs and other peat-                             grass is establishing and there is no
land species such as Carex oligosperma may also aid                              open water.
in the establishment of Sphagnum by providing shade
and protection from wind (Boudreau and Rochefort
1998) (Johnson et al 2000). Seed of some herbaceous
peatland species may be introduced to a site along with      Influence on Maintenance
the donor material. If the restoration site retains the
                                                             Maintaining water levels at or just below the soil sur-
acidic, low nutrient qualities of a bog or poor fen, then
                                                             face, providing a weed free straw mulch, and control-
invasive species are usually not a significant problem.
                                                             ling invasive species are particularly important in the
If present, invasive species such as reed canary grass
                                                             restoration of peatlands.
should be controlled with glyphosate.

Studies in Canada have shown a beneficial effect of
phosphorus fertilization on Sphagnum bog restoration
(Quinty and Rochefort 2003). The phosphorus doesn’t
directly increase Sphagnum growth, but does stimu-
late the growth of Polytrichum moss, which helps the
Sphagnum to establish. Polytrichum not only serves
as a companion species but also reduces frost heav-
ing, a common problem on peatland restoration sites.
Phosphorus fertilizer should be applied as granulated
phosphate rock, a slow release form, at a rate of ap-
proximately 130 lbs/acre. Fertilizer is not recommended
if reed canary grass is a threat.

DECEMBER 2008                                                                  5  5 E S TA B L I S H I N G W E T L A N D V E G E TAT I O N   69
     Peatland Restoration Guide, second edition. Quinty, F., Rochefort,
     Effect of mulch, companion species, and planting time on
     restoration of post-harvested Minnesota peatlands, U.S.A.,
     Johnson, K.W., Maly, C.C., Malterer, T.J.
     Summary of Results of the Pool 5 and Pool 8 Drawdowns on
     the Upper Mississippi River, River Resources Forum Water Level
     Management Task Force.

     Link to Appendix 5-B, Peatland Restoration

70   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T           M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E

 5-6 Selection and Placement of Seed and
     Plant Materials

                                                                       Topics covered in this section include:

                                                                         General Seed and Plant Material
                                                                         Seed Mix Selection
                                                                         Seed Mix Standards
                                                                         Seed Mix Development
                                                                         Selecting Plants
                                                                         Seed and Plant Placement

                                                                 General Considerations
                                                                 Many projects in the past have used native seedbanks
                                                                 or natural re-colonization for vegetation establish-
                                                                 ment. This has been successful for many projects, and
                                                                 can promotes local seed use, but cannot be relied on
                                                                 if invasive species are present, if landuse has depleted
                                                                 the native seedbank, or if sediment accumulation has
                                                                 buried the seedbank. An increasing number of proj-
Figure 5.82 Emergent Planting Zone                               ects are beginning to focus on the planting of seed
                                                                 for wetland plant communities in addition to upland

T   he information in this chapter summarizes the
    selection of seed and plant materials and provides
guidelines for their placement on project sites. There
                                                                 buffers to maximize wetland functions. Wetland seed
                                                                 can be expensive, so it is important to select appropri-
                                                                 ate mixes for the given soil and hydrologic conditions.
are many types of plant materials that can be selected           Plants, including containerized plants, pre-vegetated
for a project . An increasing number of species are              mats, bare-root plants, and transplants will jumpstart
becoming available as seed and plants. As seed and               vegetation establishment, particularly in situations
plant material can be a significant project cost, project        where fluctuating water levels or other variables related
designers should understand options for a project,               to hydrology will prevent seed
selection considerations, and where seed and plant               from establishing.
materials can most effectively be used to provide the
greatest project benefits.                                       Planting decisions should
                                                                 be made by a plant special-
The information in the previous two sections of the              ist coordinating with the site
Guide, Sections 5-4 Upland Planting and 5-5 Wetland              hydrologist, soil scientist and/or
Planting should have already been reviewed and con-              geotechnical engineer.
sidered as the decisions regarding plant selections are                                                         Figure 5.83 Mixing
being made.                                                                                                     Wetland Seed

DECEMBER 2008                                                            5  6 S E L E C T I N G S E E D M I X E S A N D P L A N T M AT E R I A L S   71
                                                                  Department of Transportation

                                                                  Minnesota Native Wildflower/
                                                                  Grass Producers Association

                                                                  Natural Resource Conservation Service
                                                                  Practice Standards

     Figure 5.84                                                  Target Plant Community
                                                                  The species that occur in sedge meadow and wet
     Seed Mix Selection                                           meadow community types have many similarities.
     Major considerations when selecting seed mixes for           Dominance of sedges vs. grasses and composites in
     projects include the project type, target plant commu-       these communities is likely determined by soil type and
     nity, seeding rates, geographic location, budget, seed       moisture conditions. State wet meadow mixes have
     availability, project maintenance requirements, and          been developed for use in establishing sedge meadows
     cover crop needs.                                            and wet meadows with the assumption that species
                                                                  will establish and sort themselves out over a few years.
     Project type
      There are many types of conservation and ecological
     restoration projects that are conducted in the state
     of Minnesota with varying goals that may include soil
     and water conservation, wildlife habitat, native seed
     production, bio-energy production, mitigation and rec-
     reation. Seed mixes tend to be designed to maximize
     the goals of individual projects. Projects may also have
     specific statutory or program requirements that may
     influence the design of seed mixes.

     Seed Mixes
     There are many seed mixes to select from in Minnesota
     including State seed mixes, mixes developed follow-
     ing NRCS practice standards, and mixes available from
     private seed vendors. Custom seed mixes can be devel-
     oped to meet specific project needs. Seed mixes should
     be selected based on how well they will meet project
     goals and individual site needs.

     Seed Mix Links
     Minnesota Board of Water and Soil Resources
                                                                  Figure 5.85

72   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                 M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
Wet prairie contains many of the same species that are
found in sedge meadows and wet meadows, however,
there are some species that are unique to wet prairies.
Wet prairies contain a number of species common to
more mesic and even dry prairies such as big bluestem
and Indian grass. BWSR Mixture W3 has been devel-
oped for wet prairie establishment.
                                                                   Seeding rates
Seed for tree and shrub planting can be obtained from
some vendors. Species that have been available include             Target seeding rates vary depending on the type of
tamarack, maples, ash, alder, and dogwood. Some                    community being restored. The target for upland tall-
vendors can collect for specific projects if given enough          grass prairie mixes is 30 - 70 seeds per square foot and
time for seed collection.                                          for short-grass prairie mixes it is around 100 seeds per
                                                                   square foot. Between 150 – 200 seeds per square foot
Table 5.20 summarizes the intended use of wetland                  are recommended for wetland mixes. The higher den-
seed mixes. These seed mixes are used throughout the               sity for wetland seed is to compensate for the higher
state for wetland restoration; mixes have been devel-              seed mortality inherent with smaller seed sizes and
oped for a wide variety of plant community types. Seed             loss due to broadcast seeding. These seed densities are
mixes can be found on the BWSR website at: www.bwsr.               based on seed counts for some species that have been                                     cleaned down to bare seed.

 Table 5.21 Use of Seed Mixes
 Wetland Type                  Mixture(s)                            Planting Notes

 Shallow marshes (Type 3),     Emergent seed mixes                   If possible, draw down water, plant emergent mix in ten
 deep marshes (Type 4), open                                         foot band where normal pool edge is expected. As plants
 water wetlands (Type 5)                                             are establishing water levels can be brought back up. Many
                                                                     emergent species will spread into open water. Container-
                                                                     ized plants or pre-vegetated mats are recommended in
                                                                     addition to seed to ensure establishment along the edge of
                                                                     open water.

 Floodplain (Type 1), sedge    Wet meadow seed mixes or cus-         Plant mixes in saturated to moist soil zone. Floodplain
 meadow & wet meadow           tom mixes to increase dominance       plantings often include three and shrub seed, seedlings or
 (Type2)                       of floodplain or sedge meadow         larger containerized plants.
                               species. Modified riparian mixes
                               may also be used for floodplains.

 Wet prairie (Type 2)          Wet prairie seed mixes                Plant wet prairie mix in saturated to moist soil zone. Plant
                                                                     upland mix where soils are expected to be dry (usually
                                                                     around 1.5 feet in elevation above pool edge).

 Shrub swamps (Type 6) &       Custom wet meadow seed mixes          Plant wetland seed mixture in saturated to moist soil zone.
 wooded swamps (Type 7)                                              Shrubs and some trees may be established as cuttings.
                                                                     Trees and shrubs can also be established with seed, seed-
                                                                     lings or containiezed plants.

 Bog (Type 8)                  Peat application from donor site      After site is prepared with peat, supplemental custom seed
                               or custom mixes.                      mix can be planted in saturated to moist soil zone.

 Riparian-stream with          Riparian seed mixes and custom        Riparian mixes are planted on the stream banks and in the
 shallow banks and             wet meadow seed mixes                 associated floodplain zone where soils are saturated to
 associated floodplains.                                             moist. Plant upland mix where soils are expected to be dry.

 Riparian-streams with long    Riparian seed mixes with upland       Riparian mix used along the lower streambank and in flood-
 and/or steep banks.           mixes                                 plain areas. The upland mix is planted going up the slopes.
DECEMBER 2008                                                             5  6 S E L E C T I N G S E E D M I X E S A N D P L A N T M AT E R I A L S   73
                                                                  cost. However, on a per seed cost many forb seeds
                                                                  are not more expensive than grasses but it generally
                                                                  depends on the species selected.

                                                                  Seed Availability
                                                                  Seed availability tends to depend on the propagation
                                                                  and demand for individual species and seasonal varia-
                                                                  tion in production.

                                                                  Propagation of individual species – Some species
                                                                  are easier to propagate from seed than others. Native
                                                                  grasses are relatively easy to germinate from seed while
                                                                  many forbs need special methods of stratification.
                                                                  There are examples of some species where no reliable
                                                                  methods have been developed to grow the plants from
                                                                  seed. The ease of propagation influences the overall
                                                                  production of species and the use of species in seed

                                                                  Demand for individual species – The demand for indi-
                                                                  vidual plant species from seed can depend on how well
                                                                  known the species is to the restoration community. The
                                                                  species most commonly seen in the landscape are the
                                                                  species that are used the most in seed mixes. This may
     Figure 5.86                                                  help the propagation of common species but not spe-
                                                                  cies that are less common. Less common species will
                                                                  also be more expensive from seed, as less seed tends
     Geographic Location                                          to be available for collection. Research and education
     Soils, climate, hydrology, and vegetation can vary           efforts play an important role in ensuring that the full
     widely across the state of Minnesota. It is common to        composition of native communities is considered when
     develop seed mixes that are suited to different areas of     designing sites and seed mixes.
     the state. Research is underway to help determine the
     appropriate distance from projects that seed may origi-      Seasonal variation in production – Like most crops,
     nate; it is a recommended practice to obtain seed that       native seed production can vary from year to year due
     originates as close to the project site as possible.         to climatic conditions, bird and animal use, insects,
                                                                  and disease. Low supply during a particular season will
     Climate change is a growing concern related to ecologi-      influence seed costs or may lead to
     cal restoration. More research is needed to determine        an increased use of substitutions
     how climate change could be factored into restoration        or cultivars.
     planning and the development of seed mixes.

     Project budget often has a significant influence on
     the number of species purchased for projects and the
     number of forbs versus grasses. CRP seed mixes from
     vendors tend to be the most inexpensive as species in                                                     Figure 5.87 Separate
     these mixes are harvested in large volume. Seed mixes                                                     Grass and Forb Bags
     arethat have increased diversity tend to have increased

74   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                 M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
Project Maintenance Requirements
Select seed mixes with an eye to the amount and type
of maintenance that will be conducted at a project site.
Ultimately, the amount of time that will be spent moni-
toring and maintaining a site will influence the diversity
that can be sustained over time. Burning, mowing, spot
treating herbicides, and grazing are strategies that can
be used to maintain diversity over time but they all
require the commitment of time and resources.

Cover Crop Needs
Cover crops are plant species that establish quickly
and are short lived, making way for slower-developing
native plants. Cover crops prevent soil erosion and
provide cover for establishing native species. Cover
crops include common grains such as oats and annual
rye grass as well as native species such as Canada and
Virginia wild rye, fowl bluegrass, and slough grass.

Recent research has indicated that cover crops in wet-
land mixes may not inhibit the growth of reed canary
grass. Cover crops in wetlands may actually delay the
establishment of native species, allowing reed canary
grass time to become established (Iannone and Gala-          Figure 5.88 Giant Bur-reed
towitsch 2008). Cover crops are generally needed in
seed mixes but appropriate percentages will be investi-      Seed Mix Standards
gated in the future.
                                                             Seed mix standards ensure that high quality local seed
                                                             is used. Seed standards include the certification of seed
                                                             source, the use of pure live seed, seed cleaned to high
                                                             standards, the verification of seed tags and standards
                                                             for substitution and shipping.

                                                             Local Ecotype Seed
                                                             The use of seed with a local genetic origin is a goal of
                                                             most restoration projects. Source-identified (yellow tag)
                                                             certified seed has a known genetic collection site from
                                                             which the germplasm was first collected. The collec-
                                                             tion site is verified and documented on the certifica-
                                                             tion label usually identifying the county of origin of
                                                             the germplasm. Currently, genetic testing is not part of
                                                             the certification process. The certification program is
                                                             operated by the Minnesota Crop Improvement Associa-
                                                             tion (MCIA). The use of the yellow tag system relies on
                                                             demand for yellow tag certified seed. The system is not
                                                             a requirement for many programs, so it has been used

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     In addition to yellow tag certification, MCIA has two ad-
     ditional levels of seed classes that differ in the amount
     of intentional selection that has taken place. “Selected”
     seed is marked with a green tag and is the progeny of
     phenotypically selected plants with traits or parentage
     that has promise but no proof of inheritance. “Tested”
     seed is marked with a blue tag and is the progeny of
     plants whose parentage has been tested and proven
     to possess distinctive traits for which the inheritance is
     stable but for which a variety has not been named or
     released. In addition, all certified seed is required to be
     tested to verify that the seed complies with Minnesota
     Seed Law requirements and to allow accurate labeling.

     It is common that projects specify an acceptable dis-         Figure 5.90 Wetland Forb and Sedge Seed
     tance for the origin of native species. As a general rule,
     plant materials should originate from as close to a proj-     expected to germinate. The number that is attained
     ect site as possible. Using local sources of seed will help   through these calculations is useful in determining the
     protect the genetics of remnant plant communities.            number of viable seeds in a unit of weight (Diboll 1997).

     Pure Live Seed                                                It should be noted that most native species take longer
                                                                   than 14 days to germinate, so tests resulting in low
     Pure live seed is a measurement of the amount of seed
                                                                   germination but high viability are not uncommon.
     that germinates in a standard (14 day) germination test
                                                                   “Standard” seed tests for germination were developed
     plus the amount found to be alive (but didn’t germinate
                                                                   for agricultural crops such as corn and soybeans. To
     in 14 days or is dormant) from a viability (tz) test. Pure
                                                                   date there have been no “standard” seed testing proto-
     live seed is determined by multiplying the percent ger-
                                                                   cols developed for seed derived from wild native plants
     mination success by the purity of seed (purity refers to
                                                                   (Jacobson 2006).
     the amount of actual seed versus stems or other plant
     material left in with the seed).
                                                                   Seed Cleaning Considerations
     The PLS number can then be multiplied by the number           If a seed supplier does not clean their seed down to
     of seeds per pound or kilogram to give an estimate of         bare seed for the listed species, then the seed test
     the number of seeds per pound or kilogram that are            must include the seed count. Additional bulk seed
                                                                   needs to be added to match the design seeding rates.
                                                                   One example of this is with Canada Blue Joint Grass.
                                                                   Some suppliers sell the seed with the lemma, palea,
                                                                   and pappus intact. Some clean this species down to
                                                                   the bare seed (careopsis). It takes about ten pounds of
                                                                   “fluffy” seed to yield one pound of bare seed. The PLS of
                                                                   un-cleaned and cleaned seed may be the same, say 90
                                                                   percent, however, the seed count per pound will vary as
                                                                   much as ten fold. There are no species-specific stan-
                                                                   dards for cleaning wetland seed; be aware of this fact
                                                                   and ask enough questions to know how many seeds
                                                                   you are getting (Jacobson 2006).

     Figure 5.89 Canada Anemone

76   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                   M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
Seed tags
The Minnesota Seed Law requires that all seed offered                  recommended that native seed vendors supply a copy
for sale in Minnesota be labeled with analysis labels. In              of the seed test for each species in the mix. In Minneso-
addition, certified seed must be labeled with a certifica-             ta, seed tests are legal for 15 months for native species.
tion label or be accompanied by a certification certifi-               If a period longer than this has transpired, it is required
cate. Project designers should compare seed tags on                    that tests be performed again. Figure 5.91 shows an
each bag with the invoice for the purchase. It is also                 example of a seed tag.

 Required labeling for MnDOT seed
 Mixture       *Total       *Total Bulk #:                         *Area Covered:                              Lot Number:
 Name:         PLS #:
 Labeler’s Name:                          Labeler’s Mailing Address:

 *Scientific   Common       *Mix %        Variety         Origin   *PLS %      *Purity %       Total           Germ %           Hard +          Pure Seed
 Name          Name                                                                            Germ %                           Dormant         %

 Germ Test Date (mm/        Weed Seed:                             Noxious Weed Seed (Name of Each Present):
 Sell By Date (optional):   Other Crop:
                                          Inert Matter:            Number per Pound:

Figure 5.91

Notes:                                                                 Mix %: PLS wieght of species divided by total PLS weight of mix
*Headings with an asterisk represent information required in
addition to Minnesota Department of Agriculture standards.             Variety: Includes Source Identified (Yellow Tag), Wild Type,
                                                                       or Variety
Also in addition to MDA standards, information is required for
all components of mix, including those that constitute less than       Origin: Location of Genetic Origin. County(ies) must be listed
5% of mix.                                                             for native species.

If large and small seed are bagged separately they must have           PLS % = (Purity x Total Germination)/100
separate tags.
                                                                       Total Germ % = (Germination %) + (Hard + Dormant Seed %)
Mixture Name: Labeling a mix as a Mn/DOT mixture requires
adherance to all applicable Mn/DOT specs.                              Pure Seed % = (Pure Seed weight of species)/(total bulk
                                                                       weight of mix)
Area covered: Area covered by amount of seed in bag when
applied at rate specified for that mix in Mn/DOT Specs,                Germ Test Date: Date for component with earliest test date.
Table 3876-5                                                           Must not be more than 15 months prior to date of sale,
                                                                       exclusive of the month of test.

DECEMBER 2008                                                                  5  6 S E L E C T I N G S E E D M I X E S A N D P L A N T M AT E R I A L S   77
     Species Substitutions                                        The first step in developing a seed mix involves creating
                                                                  a list of species based on the project goals and func-
     Due to seed supply limitations from year to year, there      tional needs. A mix developed for erosion control may
     is often the need to work out an agreeable substitution      have a different composition of species than a mix fo-
     for one or more species with seed suppliers. Substitu-       cused on species diversity and plant community recon-
     tions should be based on functional needs, the wetland       struction. When reconstructing plant communities, lists
     indicator status, genus of the substitution, and succes-     of species from remnant communities or historic lists of
     sional status of the species (Jacobson 2006).                plant communities are often used as a guide. Species
                                                                  that are not available as seed will ultimately need to be
     Shipping                                                     taken off of the list.
     Most native seed suppliers will ask how seed should be
     mixed before they ship it. Many suppliers provide the        After developing a rough species list, the final percent-
     smaller and larger seed components of a mix in sepa-         age of each species in the mix should be determined,
     rate bags to allow proper seed installation with a typical   again using the natural communities as a guide. Deter-
     seed drill used for seeding upland native mixes. State       mine species that will co-exist well without individual
     wetland mixes are often supplied as three components;        species being overly aggressive. Also consider having
     grasses, forbs, and sedges/rushes/bulrushes. The differ-     early and later successional species, having a balance
     ent components can be installed separately or mixed          of warm and cool-season species, and include grasses
     together. Most suppliers will break down the mixes into      and forbs typical to the target plant community. When
     components and provide them this way at no extra             attempting to re-create the composition of natural
     charge.                                                      communities, it is common to have around 50% of a
                                                                  mix composed of forbs. This varies depending on the
                                                                  community to be restored.
     Seed Mix Development
                                                                  Once percentages of species are determined, the next
     The development of seed mixes can be a complicated
                                                                  step is to determine the number of species planned per
     process factoring site conditions, goals, seed costs, seed
                                                                  square foot. It is common to seed between 150 - 200
     density targets, planting strategy, species diversity,
                                                                  seeds per square foot for wetland mixes. The target
     species germination potential, combining early and
                                                                  for upland tallgrass prairie mixes is 30 - 70 seeds per
     later successional species, grass to-forb-ratios, cool and
                                                                  square foot and for short-grass prairie mixes it is around
     warm season species, and historic composition of plant
                                                                  100 seeds per square foot. These seed densities are
                                                                  based on seed counts for some species that have been
                                                                  cleaned down to bare seed.

                                                                  The higher density for wetland seed is in part to com-
                                                                  pensate for the higher seed mortality inherent with
                                                                  smaller seed sizes. These rates per square foot typically
                                                                  correspond to 10 pounds PLS grasses/acre and two lbs.
                                                                  PLS forbs/acre for both wetland and upland mixes. The
                                                                  final seeding rate is 12 pounds PLS/acre (Bohnen and
                                                                  Galatowitsch 1999). This rate is doubled during broad-
                                                                  cast seeding because not all of the seed will be dis-
                                                                  persed in ideal conditions for germination (Morgan et
                                                                  al. 1995). Rates for rough cleaned, wild-collected seed
                                                                  may require a seeding rate as high as 30 to 40 pounds
                                                                  per acre, depending on the amount of plant material
                                                                  with the seed (Diboll 1997).
     Figure 5.92 Seed Bags

78   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                  M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
To determine the amount of seed of any given species           These steps should be conducted for each species in the mix.
to order, know the seed weight (seeds in an ounce) for
each species in the mix. The weight of various species         One final consideration is that more seed of species
can be determined by contacting nurseries that sell            that have small seeds should be added to a seed mix
that species. In addition, the Prairie Moon Nurseries          when using a seed drill. Seed drills place seed at a pre-
catalog provides information on average weights for            specified depth. This depth is often not ideal for very
many species. Weighing certain amounts of seed and             tiny seed, which needs to be planted at very shallow
counting the number of seeds in the sample can also            depths or simply dispersed on the soil surface. Increas-
determine seed weight. Seed size can vary greatly from         ing the quantity of small seed in a seed mix ensures
the large seeds of compass plant and cup plant with            that some of the seed will germinate. Following the
around 800 seeds per ounce, to the very small seeds            previous example using fox sedge, to increase by ten
of cardinal flower, blue lobelia, and Culver’s root with       percent: 8.7 ounces x 0.10 (ten percent) = 0.87; add this
around 800,000 seeds per ounce (Diboll 1997).                  to the original amount: 8.7 + 0.87 = 9.57 ounces.

Determining Ounces Needed Per Species                          Selecting Plants
The best method of determining the number of ounces
needed for each species is to start with the number of
seeds that are planned per square foot. For this ex-
ample, let’s assume that 200 seeds per square foot will
be planned for a wetland seeding. The next step is to
multiply the percentage of individual species in the mix
by 200 to determine how many seeds of each species
will be found in the one square foot of area. For exam-
ple, if fox sedge will make up 10% of the mix, multiply
0.10 by 200 to determine that 20 fox sedge seeds would
be needed per square foot: (200 seeds per square foot
x 10% or 0.1 = percent of fox sedge in the mix = 20 fox
sedge seeds per square foot.)

Once the number of seeds needed for each species for           Figure 5.93 Planting containerized
one square foot is known, that number can be multiplied        plants, Photo by Prairie Restorations, Inc.
by the number of square feet that make up the entire           Plants are often used in addition to seeds or in some
project area. If the project site is 43,560 square feet (one   cases without seeding. Plants are used in situations
acre) then 43,560 square feet would be multiplied by 20        where seed may not establish or rapid establishment
to determine the number of fox sedge seeds needed for          is needed such as along the edge of open water or
the project: (43,560 ft2 (entire project area) x 20 (num-      areas prone to erosion or flowing or fluctuating water.
ber of fox sedge seeds in one square foot) = 871,200 fox       Some species do not do well from seed and are often
sedge seeds needed for the project).                           planted as mature plants. It is also common to plant
                                                               trees and shrubs as plants to increase the rate of site
The final step is to divide the number of seeds needed         establishment.
by the number of seeds per ounce for a species. Fox
sedge has 100,000 seeds per ounce. 872,000 should be           There are many options available for the establish-
divided by 100,000 to determine the number of ounces           ment of plants in wetlands and uplands. Containerized
needed for the species:                                        herbaceous plants are the most common type of plant
                                                               material used along with bare-root trees and shrubs.
871,200 (number of fox sedge seeds for entire project)
_____________________________________________                  Other options include pre-vegetated mats, bare-root
100,000 (number of seeds in an ounce of fox sedge)             herbaceous species, containerized trees and shrubs,
= 8.7 ounces of fox sedge seed                                 and transplanted vegetation. The selection of plant ma-

DECEMBER 2008                                                         5  6 S E L E C T I N G S E E D M I X E S A N D P L A N T M AT E R I A L S   79
     terials for a project should be based on site conditions,
     project goals, and budget. It is recommended to work
     with nurseries to fully understand options for a project
     and the costs, benefits, condition, and availability of
     plant materials being considered.

     Contract Growing Plants
     Contract growing wetland plants is a good way to
     ensure that the species desired for a project will be
     available. Contract growing also allows for use of lo-
     cal sources of seed to grow wetland plants. Nurseries
     should be contacted as early as possible to discuss
     contract growing. Plugs can be grown between early            Figure 5.95
     spring and June. Plants in larger containers may take
     one full growing season or longer to become fully             Upland Planting, Upland Containerized Plants and
     rooted in their containers. It is important that everyone     Rootstock (Section 5-5)
     understands the timeline for a project and how long it
     will take to grow the desired plant materials.                Upland Planting, Upland Trees and Shrubs
                                                                   (Section 5-5)
     Plant Specifications
                                                                   Wetland Planting, Wetland Containerized Plants
     When purchasing wetland plants, pay attention to              and Rootstock (Section 5-6)
     the quality of the plant material. Plant roots should be
     about the same density as aboveground growth. Roots           Wetland Planting, Wetland Trees and Shrubs
     should extend to the bottom of the container and have         (Section 5-6)
     well developed rhizomes in addition to root hairs. If
     contract growing, make sure that the grower under-
     stands the project plant specifications and expected          Seed and Plant Placement
     planting date (Hoag 2000).
                                                                   The distribution of wetland and upland seed mixes and
     Inspect plant materials upon delivery to the site to          plant materials at a site are based on the planned site
     ensure the shipment includes the correct species, is          conditions including soils, topography and hydrology.
     appropriately labeled,                                        Information about soils, hydrology, existing vegetation
     and that the plants                                           observed during site visits, and information collected in
     were not damaged                                              the office, will be useful in placement of both wetland
     during transport. Plan                                        and upland plant species. As the location of seed mixes
     for a shady area at the                                       and plant materials are selected for a project, their loca-
     restoration as a stag-                                        tion should be shown on the planting zone map that is
     ing area for delivered                                        prepared as part of the vegetation plan.
     plants. If shade trees
     are not available, pro-                                       Mixes focused on emergent species are often placed
     vide shade by erecting Figure 5.94 Photo by Prairie           in a ten foot band around the planned wetland water
     tents or other con-       Restorations, Inc.                  edge and are installed after water levels have stabilized
     structed shade struc-                                         and are somewhat predictable. Wet meadow and sedge
     tures. Along with shade, there should be a water source,      meadow mixes are used from the planned water edge
     especially when planting bare root plants on warm days        to 1.5 to 2 feet higher in elevation. The elevation above
                                                                   the water edge that wet meadow and sedge meadow
     The following sections present specific strategies for        are used should be based on the soil holding capacity
     selecting and planting both upland and wetland plant          of the soil. Heavy soils tend to draw water approxi-
     materials and includes discussions of the following topics:   mately one foot above the water level due to capillary
80   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                   M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
                                          action while sandy soils draw water up approximately 6

                                          Soils will have a significant role in the distribution of
                                          prairie seed mixes. Wet prairie species will require soil
                                          saturation within 12 inches of the surface. Mesic prairie
                                          species require soils that remain moist and dry prairie
                                          species are adapted for dry soils. The transition from
                                          wet meadow, sedge meadow and wet prairie mixes to
                                          upland prairie mixes commonly occurs at about 1.5 to 2
                                          feet above water levels.

                                          It is recommended to overlap seed mixes a few feet,
                                          particularly between wetland and upland mixes to en-
                                          sure that seed mixes will be located to take advantage
Figure 5.96 Broadcast Seeding, Photo by   of changing hydrologic conditions.
Rusty Schmidt

Figure 5.97

DECEMBER 2008                                    5  6 S E L E C T I N G S E E D M I X E S A N D P L A N T M AT E R I A L S   81
        Plant Community Planting Recommendations
        Upland                     Sedge Meadow                                Shallow Marsh                 Deep Marsh               Shallow, Open Water
        Prairie                    Fresh (Wet) Meadow
                                   Wet Prairie
                                   Shrub Swamp

                                   (Communities with similar
                                   hydrology but differences in
                                   species dominance)

      1.5 feet above
      pool elevation

                               Capilary fringe .5 feet
                                                             Pool Elevation
      Seeding with             above pool elevation
      upland mixes             in sand
      (BWSR U1-U9,
      U13-U15, U16,            Seeded with wet meadow and sedge
                              Seeded with wet meadow, sedge meadow            Seeded with emergent
      U17)                     and wet prairie mixees
                              meadow mixes (BWSR W2) for Sedge                wetland mixes (BWSR W1).
                              Meadows, Fresh (Wet) Meadows and                Mixes are often seeded in
      Containerized           Shrub Swamp. Seeded with Wet prairie            a6
                                                                              10 foot band straddling    Planted with containe-
      plants used for         mixes (BWSR W3) for Wet Prairie.                open water.                rized plants, transplants
      some species                                                                                       and tubers. No seeding is    Planted with containerized
      difficult to            Containerized plants used for some              Containerized plants,      generally conducted.         plants, transplants, tubers and
      establish from          species difficult to establish from seed.       transplants, and pre-vege-                              plant fragments. No seeding is
      seed.                                                                   tated mats are planted at                               generally conducted.
                                                                              the edge of open water.

     Figure 5.98 provides detailed guidelines for planting seed mixes and plant materials for specific plant
     communities and corresponding hydrology conditions.

     The planned topographic and hydrologic conditions                                 band is shown in Figure 5.100. As hydrology conditions
     for a site typically have ther greatest influence on the                          change rapidly with steep slopes, the width of seeding
     type and distribution of seed mixes. As wetland seed                              zones are narrower than when shallow slopes lead into
     needs light to germinate and is susceptible to sediment                           a wetland. It is common to have higher plant diversity in
     accumulation, steep slopes will require seeding meth-                             situations with shallow slopes as there is more surface
     ods to stabilize the uplands. In some cases, temporary                            area for plant species and subtle changes in hydrologic
     cover crops may be established during the spring to                               conditions. Figures 5.99 and 5.100 show a wetland
     stabilize slopes. These cover crops are lightly disked                            with steep slopes while Figure 5.101 and 5.102 show a
     before permanent seeding in the fall. In this example,                            wetland with gradual slopes.
     temporary cover crops are being planted in areas that
     will have standing water. Temporary cover crops will                              In Figure 5.102, gentle slopes are shown extending
     help stabilize soils as available native seed banks ger-                          into a wetland with hydrology to the soil surface. In this
     minate. Another option for stabilization is to establish                          case, a sedge meadow mix is planted across the entire
     permanent upland mixes before the seeding of wet-                                 basin; there is no emergent vegetation zone. Erosion is
     land areas. Once the uplands are established, wetland                             less of a concern in this example but if site preparation
     seeding can be conducted. As water levels may change                              is completed in the spring it may still be desirable to
     rapidly in wetlands with steep side slopes, the timing                            plant a temporary cover crop in preparation of seeding
     of seeding emergent vegetation can be an important                                a permanent seed mix in the fall. The temporary cover
     consideration. In many cases, it is best to allow water                           crop will provide time for additional weed control. If
     levels to stabilize in later spring and to seed the open                          the site is coming out of agriculture in the fall, it may
     water edge when water levels are slowly receding. It is                           be ready for broadcast seeding and little additional
     common to seed a narrow band/zone of emergent spe-                                site preparation may be required. During a fall seeding,
     cies along the edge of open water. An example of this                             mulch is recommended to hold soil and help seedlings
82   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                                             M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
                                                           Figure 5.101 Topography of a Typical Drained Sedge
Figure 5.99 Topography of a Typical Drained Deep           Meadow Wetland
Water Wetland

                                                           Figure 5.102 Restored Sedge Meadow Wetland

                                                           nization can sometimes be relied on to aid vegetation
Figure 5.100 Deep Marsh Wetland Restored                   establishment but rapidly spreading cattails can often
                                                           inhibit the growth of planted species.
establish in the spring. Figure 5.100 shows the use of
a temporary cover where there will be standing water.      It is common to plant emergent vegetation staggered
The temporary cover will stabilize soils while hydrology   along the edge of open water and allow it to spread
is restored.                                               into deeper water. Emergent vegetation is often
                                                           planted along with seed to ensure establishment in
Plant materials are commonly used in combination           case either the seed or containerized plants fail.
with seed when establishing vegetation in deeper
water habitats. Plants should be strategically placed to   Native seedbank and natural recolonization can some-
maximize their benefits for vegetation establishment.      times be relied on for the establishment of vegetation
It is common to plant submergent and floating leaved       in open water communities.
species between six inches and two feet deep depend-
ing on individual species. Seed banks and natural colo-

DECEMBER 2008                                                     5  6 S E L E C T I N G S E E D M I X E S A N D P L A N T M AT E R I A L S   83
     The following table summarizes plant materials that are commonly available and general spacing recommendations.
     In the table below, bare root refers to the planting of any type of bare root system (rhizomes, root fragments etc.)
     Spacing is based on the mature size of plants and rate of spread.

         Table 5.22 Propagule Type and Spacing for Wetland Plant Species
         Common Name                                Scientific Name                      Type of Plant Material                           Spacing
         Sweet Flag                                 Acorus calamus                      Seed, bare root, container                       3-4 ‘
         Swamp Milkweed                             Asclepias incarnata                 Seed, bare root, container                       2’
         Panicled Aster                             Symphyotrichum lanceolatus          Seed , bare root, container                      3’
         Red-stemmed Aster                          Symphyotrichum puniceus             Seed, bare root, container                       2’
         Canada Blue-joint Grass                    Calamagrostis canadensis            Seed, bare root, container                       2’
         Wild Calla                                 Calla palustris                     Bare root, container                             2’
         Marsh Marigold                             Caltha palustris                    Seed, bare root, container                       2’
         Slough Sedge                               Carex atheroides                    Seed, bare root, container                       3’
         Bebb’s Sedge                               Carex bebbii                        Seed, bare root, container                       2’
         Bottlebrush Sedge                          Carex comosa                        Seed,bare root, container                        2’
         Lake Sedge                                 Carex lacustris                     Seed, bare root, container                       3’
         Tussock Sedge                              Carex stricta                       Seed, bare root, container                       2’
         Fox Sedge                                  Carex vulpinoidea                   Seed, bare root, container                       2’
         Turtlehead                                 Chelone glabra                      Container                                        2’
         Creeping Spikerush                         Eleocharis palustris                Seed, bare root                                  3’
         Joe-Pye Weed                               Eupatorium maculatum                Seed, bare root, container                       3’
         Boneset                                    Eupatorium perfoliatum              Seed, bare root, container                       2’
         Rattlesnake Mannagrass                     Glyceria canadensis                 Seed, container                                  2’
         Sneezeweed                                 Helenium autumnale                  Seed, container                                  3’
         Giant Sunflower                            Helianthus grosseserratus           Seed, bare root, container                       4’
         Blue Flag Iris                             Iris versicolor                     Seed, bare root, container                       3’
         Soft Rush                                  Juncus effusus                      Seed, bare root, container                       2’
         Slender Rush                               Juncus tenuis                       Seed, container                                  2’
         Prairie Blazingstar                        Liatris pycnostachya                Seed, bare root, container                       2’
         American Lotus                             Nelumbo lutea                       Bare root, container                             5’
         White Water Lily                           Nymphaea tuberosa                   Bare root, container                             5’
         Sensitive Fern                             Onoclea sensibilis                  Bare root, container                             2’
         Sago Pondweed                              Potamogeton pectinatus              Bare root, container                             5’
         Pickerelweed                               Pontederia cordata                  Bare root, container                             2’
         Big-leaved Arrowhead                       Sagittaria latifolia                Seed, bare root, container                       4’
         Hardstem Bulrush                           Schoenoplectus acutus var. acutus   Seed, bare root, container                       4’
         Green Bulrush                              Scirpus atrovirens                  Seed, bare root, container                       3’
         Woolgrass                                  Scirpus cyperinus                   Seed, bare root, container                       3’
         River Bulrush                              Schoenoplectus fluviatulis          Seed, bare root, container                       4’
         Softstem Bulrush                           Schoenoplectus tabernaemontani      Seed, bare root, container                       4’
         Giant Bur-reed                             Sparganium eurycarpum               Seed, bare root, container                       4’
         Prairie Cord Grass                         Spartina pectinata                  Seed, bare root, container                       4’
         Wild Celery                                Vallisneria americana               Bare root, container                             4’
         Culver’s Root                              Veronicastrum virginicum            Seed, bare root, container                       3’
         Wild Rice                                  Zizania aquatica                    Seed

84   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                                M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E

 5-7 Vegetation Plan Implementation

                                                                     This chapter summarizes the steps involved in
                                                                     preparing for project implementation. Topics
                                                                     covered in the chapter include the following:

                                                                        Reviewing the Vegetation Plan
                                                                        Pre-bid Meetings
                                                                        Bidding and Contractor Selection
                                                                        Measurement and Payment
                                                                        Permits and Certification Requirements
                                                                        Pre-implementation Meetings
                                                                        Layout and Staking
Figure 5.103                                                            Handling Restoration Materials
                                                                        Project Coordination and
Reviewing the Vegetation Plan                                              Communication
                                                                        Site Inspection and Vegetation

T    he final vegetation plan prepared for a project
     should include the project overview, planting zone
map, project details, project specifications and notes,

and project schedules. Time should be taken to review
the vegetation plan to ensure that it is complete. It               Project Scope
is important that all of the components are working
together to provide sufficient detail for contractors
to be able to conduct the installation. The vegetation              Bid Information
plan may need additional refinement as the installation             Project Schedules
project begins, particularly if site conditions and project         Property Boundaries
schedules change.                                                   Measurement and Payment
                                                                    Performance Standards.
Pre-bid Meetings
                                                                 Essentially, the pre-bid meetings are intended to help
Pre-bid meetings are recommended for larger projects             everyone understand the details of the project. The pre-
to review the scope of work with contractors interested          bid meeting provides an opportunity for contractors to
in bidding on the project. The pre-bid meeting, usually          ask questions about the project before submitting a bid.
includes discussions by the project designer about the fol-
lowing topics:                                                   Bidding and Contractor Selection
  Submission Dates                                               If contractors will be selected through a bidding
  Permit Requirements                                            process, it is essential to develop project specifications
  Bonding Requirements                                           that are clearly understood, practical, and enforceable.
  Prequalification Requirements                                  Performance standards aid in setting expectations for a
                                                                 project in preparation for bidding.
  Payment and Completion Dates
  Site Access

DECEMBER 2008                                                                       5  7 V E G E TAT I O N P L A N I M P L E M E N TAT I O N   85
                                                                  When using a public bid process, specifications must
                                                                  clearly spell out the level of experience that is accept-
                                                                  able for the project. Appendix 5-B summarizes specifi-
                                                                  cations for bidding and contractor selection.

                                                                  Link to Appendix 5-B, Bidding and Contractor
                                                                  Selection Specifications

                                                                  Measurement and Payment
                                                                  Measurement and payment refers to the measure-
                                                                  ment of how restoration implementation activities will
                                                                  be compensated. For example, mowing may be paid
                                                                  for by the acre or by the hour. It is important to clarify
                                                                  how each activity defined in the vegetation plan will
                                                                  be paid for. It is most common that activities related to
Figure 5.104                                                      vegetation establishment are bid by the acre. There are
                                                                  exceptions where activities such as spot treatment of
     Quality of work can be maximized by hiring contractors       weeds or watering are paid for by the hour to ensure
     that have a good reputation and a great deal of experi-      that sufficient time is spent for the activity.
     ence. It is recommended when possible to work with
     contractors that can conduct all aspects of site prepara-    It is recommended to bid project construction and
     tion, planting, and maintenance work to keep consis-         implementation together with project maintenance ac-
     tency through the length of the project. The vegetation      tivities through the first three to five years. It is common
     plan should be as specific as possible to achieve the        to bid separate contracts for long-term maintenance
     best results. For example, on a large or complex site        activities based on site conditions.
     that has a reed canary grass infestation, the specifica-
     tions should require a contractor with demonstrated
     experience in long-term control of reed canary grass.
                                                                  Permit and Certification
     Government entities, such as the State of Minnesota,
     typically hire contractors by:                               DNR Waters
     1) A sealed bid advertised through the Construction          The Minnesota Department of Natural Resources is in
        Bulletin; or                                              charge of issuing permits for work to be conducted
     2) Soliciting professional services via a request for        within waterbodies designated as protected waters.
        proposal (RFP) in the State Register.                     The DNR “data deli” has GIS layers of the waters of the
                                                                  state. DNR staff can provide information about when a
     Units of government are subject to specific laws, rules,     permit is needed.
     and procedure that must be followed when contracting
     for services.                                                Prescribed burning
                                                                  It is often necessary to obtain a burn permit from the
     The laws that apply to a unit of government are com-
                                                                  Mn DNR Forestry office with additional approval by the
     plex and subject to change. It is important that con-
                                                                  local fire department. This permit usually includes a
     tracts for local units of government, state departments,
                                                                  requirement to notify the sheriff ’s office and/or the lo-
     and federal agencies are compliant with the laws and
                                                                  cal fire department on the day of the burn. Permits may
     rules that govern the unit of government. In order to
                                                                  also require a detailed burn plan. Requirements vary
     minimize inadvertent violations of applicable contract-
                                                                  in different regions, so be sure to obtain information
     ing law, legal counsel should approve all substantial
                                                                  ahead of time when planning a burn.
     government contracts.

86   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                  M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
Figure 5.105

Herbicide use                                               restoration strategies will be coordinated. Pre-imple-
                                                            mentation meetings should also include a discussion
All personnel applying chemicals must have a Commer-        of how the project will be managed and how effective
cial Herbicide Applicator License. The only exception       communication can be maintained among project
is for landowners who are applying herbicides on their      designers and contractors. Additional topics that are
own property. The Minnesota Department of Agricul-          covered during pre-implementation meetings include:
ture administers the herbicide certification program.
                                                              Requirements of the Contract
Link to Appendix 5-B Permit and Certification
Requirement Specifications                                    Permit Requirements
                                                              Scope of Work
Pre-implementation Meetings                                   Project Schedules
                                                              Equipment Cleaning
Pre-implementation meetings are an important step to          Site Access
ensure that everyone understands the implementation           Property Boundaries
process. Pre-implementation meetings should be at-            Staging Area
tended by project designers, contractors, and any other
                                                              Material Storage
project partners that will have a role in the implementa-
                                                              Work Hours
tion process. During pre-implementation meetings, all
components of the vegetation plan should be covered           Permits and Certification Requirements
including the project overview, specifications, notes,        Project Meetings and Communication
details, the planting zone map, and project schedules.        Site Inspection Schedule
Project schedules should be discussed so that all con-        Measurement and Payment
tractors understand how engineering and vegetation            Change Orders
portions of the project work together and how various         Safety

DECEMBER 2008                                                               5  7 V E G E TAT I O N P L A N I M P L E M E N TAT I O N   87
     Layout and Staking
     Project layout involves marking project boundaries, tran-
     sitions between seeding zones, and specific locations
     for trees, shrubs, or other specific types of plant mate-
     rial. It is best to use color-coded flags to keep flagging
     understandable. When marking the transition between
     seeding zones, careful attention should be paid to site
     elevations. Attention to survey markings will ensure
     that seed mixes are located at the appropriate eleva-
     tion. Flags must be placed close enough together to be
                                                                  collect all seed tags for the project and ensure that the
     recognized by seed installers.
                                                                  seed tags are accurate. Seed tags may be requested from
                                                                  installation contractors as part of payment requests.
     Link to Appendix 5-B, Layout and Staking Specifications
                                                                  Upon the delivery of seed, the contractor should
     Handling Restoration Materials                               provide for storage in a cool, dry environment until
                                                                  the seed is delivered to the site on the selected day of
     Before plants are delivered to a restoration site, systems   installation. If the seeding takes more than one day, all
     should be in place to check materials to ensure that         seed should be protected from the elements and stored
     deliveries include the correct species, are appropri-        in a secure, cool, dry location overnight. No seed should
     ately labeled, and were not damaged during transport.        be stored overnight in the field.
     A shady area at the
     restoration site should                                      Between purchase and installation, seed should be
     be prepared as a stag-                                       stored at approximately ten degrees Celsius (50º F) and
     ing area for delivered                                       50% humidity. Seed should be protected from moisture
     plants. If shade trees                                       before seeding. Wet or molding seed should not be used.
     are not available,
     provide shade by                                             Project Coordination and
     erecting tents or other                                      Communication
     constructed shade
     structures. Along with                                       A well-developed vegetation plan will help get a proj-
     shade, there should                                          ect off to a good start and is the first step in ensuring
     be a water source,                                           good communication. Pre-bid and pre-implementation
     especially when plant-                                       meetings are important steps to ensure that con-
     ing bareroot plants                                          tractors understand the vegetation plan. The imple-
     on warm days. Many                                           mentation schedule should be reviewed during the
                               Figure 5.106 Flagging of
     wetland species also                                         pre-implementation meeting. It will act as a guide for
                               Seed Zones
     need a temporary wet                                         everyone involved in the project to ensure that work is
     storage area.                                                completed on time and in the correct sequence.

     Seed has specific requirements to ensure that it main-       The project designer or a representative should be on
     tains viability. The seed vendor is responsible to deliver   site as much as possible as the project is implemented
     all seed in properly labeled bags, mixed in accordance       and periodically to inspect the work. One project man-
     with the installer’s specifications and to the location      ager representing the contractor oversees the construc-
     specified by the installer. Upon delivery, an invoice        tion of a project and acts as the main contact between
     should be presented to the project manager that              consultants and designers. The project manager is
     matches the total pounds of Pure Live Seed of each           responsible for overseeing the entire construction
     mix purchased by the project manager and the total           process and ensuring that engineering and vegetation
     bulk weight delivered. The project manager should also       portions of the project are compatible.

88   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                  M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
Nearly any project can take an unexpected turn, getting    An important role of the project manager involves
the project off schedule and requiring quick decisions     inspecting work to ensure that the project is being
from consultants and contractors. Examples include         installed as planned and that the project can be imple-
large storms that cause erosion or loss of seed, mechan-   mented as scheduled. Timely site inspections can help
ical problems with equipment, and excessive establish-     catch problems before they get out of hand and pro-
ment of weed species. When unexpected problems             vide an opportunity to correct them, hopefully keeping
occur, good communication will result in timely and        the project on schedule.
cost effective solutions. Being prepared for as many
variables as possible ahead of time will help make a       Site inspections should also be conducted for mainte-
project go smoothly even under adverse conditions.         nance activities such as mowing, herbicide treatment,
                                                           and prescribed burning. Inspections for vegetation
Site Inspection and Vegetation                             should not be done right after a mowing because
                                                           plants will be nearly impossible to identify. Six to eight
Establishment                                              weeks should elapse before seedlings have grown
Setting establishment goals through performance            enough to identify following a mowing. Wetland
standards helps managers to determine if projects are      fringes and sedge/wet meadows usually are not
developing as planned and if, ultimately, they meet the    mowed, so inspections can be done in mid-season
anticipated project goals. If written and communicated     and in late season.
clearly to contracted staff, performance standards serve
as milestones to show progress towards the goal.

Figure 5.107

DECEMBER 2008                                                                5  7 V E G E TAT I O N P L A N I M P L E M E N TAT I O N   89
     Figure 5.108 Wild Rice

90   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T   M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E

 5-8 Maintenance for Vegetation Establishment

                                                                     Maintenance strategies for project
                                                                     establishment covered in this chapter include:

                                                                        Herbivore Control
                                                                        Mowing for Establishment
                                                                        Herbicide Application for Establishment
                                                                        Hand Weeding
                                                                        Hydrology Control for Vegetation

Figure 5.109 ATV Gas Powered Mower

T   he information in this chapter summarizes wetland
    and buffer maintenance strategies for the estab-
lishment phase of a project. As a vegetation plan is
developed, information should be incorporated from
this chapter that meets individual project needs.                A combination of site monitoring and frequent mainte-
                                                                 nance visits during establishment are essential steps for
                                                                 any restoration and will help get a project off to a good
Maintenance Strategies for Project
                                                                 start. An adaptive approach for maintenance allows
Establishment                                                    plans to be adjusted to compensate for changing site
                                                                 conditions and, when needed, to combine multiple
Strategies included in this chapter represent the tech-
                                                                 strategies to effectively control problem species.
niques that are commonly used during the first few
years of a project as vegetation is establishing. Addi-
                                                                 Mowing is typically necessary for the establishment of
tional strategies included in Section 6 (Monitoring and
                                                                 upland plantings, but spot treatment of problematic
Maintenance) are used for maintaining vegetation after
                                                                 weeds and prescribed fire are other common strategies.
                                                                 In the case of wetlands, mowing is conducted if hydro-
                                                                 logic conditions allow and soils will not be disturbed.
                                                                 Spot treatment of weeds is a common maintenance
                                                                 strategy in wetlands as is the control of water levels.
                                                                 Maintenance strategies that are selected for a project
                                                                 should be summarized in the maintenance schedule for
                                                                 the vegetation plan.

                                                                 Invasive species that are common to restored wetlands
                                                                 include reed canary grass (Phalaris arundinacea), purple
                                                                 loosestrife (Lythrum salicaria), narrow-leaved cattail
                                                                 (Typha angustifolia), hybrid cattail (Typha x glauca), and
                                                                 the introduced genotype of reed or cane grass (Phrag-
Figure 5.109 Rotary Mower                                        mites communis). Refer to Appendix 5-A for specific
                                                                 guidance and management schedules for invasive spe-
                                                                 cies common to restored wetlands and upland buffers.

DECEMBER 2008                                                          5  8 M A I N T E N A N C E F O R V E G E TAT I O N E S TA B L I S H M E N T   91
      Table 5.23 Comparison of Project Establishment Maintenance Strategies

      Technique                             Use/Considerations                                           Relative Costs

      Herbivore Control                     Should be considered for all projects to minimize loss       Medium/High – Can vary greatly from
                                            of seedlings. Need will depend on the type of planting       relatively low costs related to flagging
                                            and project size.                                            tape strung between stakes to inhibit
                                                                                                         geese to high costs for wire fencing
                                                                                                         around trees to prevent deer browsing

      Mowing for                            Necessary during the first two years for establishment       Low - Range from $20 to $80 per acre
      Establishment                         of upland prairie plantings. Beneficial in wetland plant-    depending on the acreage to be mowed.
                                            ings to control weeds if mowing will not disturb the soil
                                            and wetland hydrology will not sufficiently minimize
                                            upland weeds.

      Herbicide Application                 Spot treatment of perennial weeds is an important step       Medium - Range from $70 to $150 per
      for Establishment                     in managing wetlands during establishment. Backpack          acre depending on the herbicide being
                                            or mechanical spray equipment is used.                       used and the number of acres to be

      Hand Weeding                          Not cost-effective for large areas. Can be useful to man-    High - Transportation for crews and
                                            age competition-sensitive species.                           hourly wages.

      Hydrology Control                     Provides favorable growing conditions for seedlings.         Low - For long-term management,
      for Vegetation                                                                                     though initial costs for control structures
      Establishment                                                                                      tend to be high.

      Watering                              If available, water control structures can be used. Water-   Medium - Trucks or irrigation requires
                                            ing with trucks or irrigation systems is an option but not   staff time and specialized equipment.
                                            practical for large restoration sites.

     Herbivore Control                                                            The size and location of a restoration can influence the
                                                                                  amount of predation that may occur. Large restora-
     Overview                                                                     tions where many acres of vegetation are establishing
                                                                                  may not be significantly impacted by herbivores as the
     Newly planted wetlands and up-                                               impact is spread across the entire site. Urban restora-
     lands can be very attractive to wild-                                        tions can be more prone to herbivory due to limited
     life as a food source. Wetland plugs                                         food sources for species such as deer and muskrats and
     and woody tree and shrub seedlings                                           large populations of geese. Carp are a significant threat
     are subject to predation by insects,                                         to emergent and submergent vegetation and can be a
     deer, muskrat and other animals                                              factor in urban as well as agricultural areas of the state.
     (Marburger, 1993). Geese can be
     a serious problem in urban areas                                             Equipment/Materials
     if there is a large resident popula-
     tion nearby. They will pull up newly Figure 5.111                            Wire fencing, Stakes, Flagging tape, Tree tubes, Deer
     planted seedling plugs and will        Stem Protection                       repellents, Bud caps, Stem protection.
     graze newly germinating plantings. Deer will also graze
     seedling vegetation as well as tree and shrub buds.
     Rabbits can damage newly planted trees and shrubs by
     eating bark during winter months.

92   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                                     M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
Figure 5.112

Typical Strategies                                         planting and then re-applying about a month later
                                                           (Tracy 2008). Deer have also been detered through the
Geese Control - There are various ways of dealing with     use of solar powered electric fencing.
unwanted predation by geese ranging from scarecrows,
noisemakers, trapping, and even chasing off with           Rabbit Control – Rabbits can damage newly planted
trained dogs. Stakes with flagging tape strung between     trees and shrubs by eating bark during winter months.
them are often used in areas where emergent vegeta-        Wire fencing or other bark protection can be used to pre-
tion is planted in open water. The flagging tape pre-      vent damage from rabbits. Rabbits can also chew buds
vents geese from landing and does not leave enough         of seedling trees and shrubs, particularly when snow is
room for them to take off.                                 deep and lower branches can be reached. Wire exclo-
                                                           sures or bud caps can be used to minimize this problem.
Deer Control - Deer exclosures created with welded
wire fencing have been the most effective method for       Carp Control – Water control sturcutres should be de-
protecting young trees. In wetlands that are seeded to     signed to prevent carp from entering a restoration site.
many acres, deer will not have a significant impact on     If carp are already in a wetland system that is being
overall establishment. Bud caps are sometimes used to      restored, they should be controlled before planting to
protect seedling trees and shrubs, particularly ever-      eliminate the needs for exclosures to protect submer-
greens. Deer exclosures can also be established with       gent and emergent vegetation. Two methods of control
wire fencing to prevent damage from deer. Deer repel-      include lowering water levels or applying chemicals to
ling sprays that commonly include ingredients such as      kill fish. If carp cannot be controlled, wire exclosures are
cayenne pepper, garlic, and rotten eggs are available      needed. It is likely that carp will prevent the plants from
to prevent grazing, however, these sprays need to be       expanding past the exclosures. Wire exclosures for carp
re-applied after rains and are not practical for large     can also prevent herbivory by muskrats. See Appendix C
areas. One approach that has been successful involves      for exclosure details.
spraying plants when they are still in containers before

DECEMBER 2008                                                   5  8 M A I N T E N A N C E F O R V E G E TAT I O N E S TA B L I S H M E N T   93
     Influence on Other Strategies                                             Mowing and raking can be used in estab-
                                                                                 lished upland plantings in place of fire to
     The control of herbivores will support the estab-                           prevent a thick thatch layer from estab-
     lishment of native vegetation and competition                             lishing. This method is not as effective as
     with weeds, minimizing additional maintenance.                           burning for maintaining diversity and con-
                                                                             trolling species such as smooth brome and
     Resources                                                               quackgrass. Mowing a prairie before a burn
     Deer Predation on a White Cedar Restoration Project in                   can help keep flame heights lower.
     Northwestern Wisconsin, Wagner, H.
     Minnesota SWCD Tree Handbook, USDA
                                                                             More information is needed about mowing
                                                                   in newly restored wetlands. Wetland margins can be
     Link to Appendix 5-B, Herbivore Control Specifications        mowed along with uplands as long as equipment does
                                                                   not cause compaction or soil disturbance. Wetlands will
     Link to Appendix 5-C, Restoration Details/Diagrams            not require mowing to the extent that upland plantings
                                                                   will, as most agricultural annual and biennial weeds are
                                                                   not adapted for saturated soil. Exceptions include spe-
                                                                   cies such as giant ragweed, Canada thistle, and nettle
     Mowing for Establishment                                      that can grow in the wetland boundary. If mowing is
                                                                   desired in wetlands and mechanical equipment cannot
     Overview                                                      be used, brush saws with scythe attachments can be
                                                                   used. Spot herbicide treatment of weeds is a common
     Recently restored uplands and wetlands can be invaded
                                                                   practice in wetlands and may be used along with mowing.
     by annual and biennial weeds such as foxtail, velvet
     leaf, lambsquarter, purslane, nut sedge, and ragweed,
     among other species, whose seeds either blow in from          Equipment/Materials
     surrounding areas or were part of the seed bank. Mow-         Flail mowers and in some cases stalk choppers are used
     ing is an essential step to the establishment of upland       to mow upland plantings and wetland edges. Flail
     prairie plantings, involving several mowings the first year   mowers and stalk choppers cut material into finer par-
     and one or two mowings the second year. Mowing will           ticles than sickle bar mowers. Brush saws with scythe
     prevent weed seeds from establishing and will give            attachments can be used for mowing smaller areas.
     native plants sufficient light as they establish. A study
     in Iowa found that areas left un-mowed after planting         Typical Strategies
     had eight species while areas that were mowed had 27
     species, stressing the importance of mowing to facilitate     Proper management includes mowing newly seeded
     seedling establishment (Kurtz, 2001).                         prairies and wetland margins to around six to eight
                                                                   inches the first year. Additional mowing in years two
                                                                   and three may also be necessary. Weedy annual and
                                                                   biennial species that may establish in wetlands do not
                                                                   pose as much of a problem as upland weeds. Standing
                                                                   water eliminates common weeds such as foxtail (Boh-
                                                                   nen and Galatowitsch, 1999). However, wetlands that are
                                                                   not inundated may have significant competition from
                                                                   weeds and should be mowed as long as equipment will
                                                                   not create ruts in the substrate. Invasive species such as
                                                                   Canada thistle should be mowed before seeds are fully

     Figure 5.109

94   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                   M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
 Table 5.24 Typical Mowing Maintenance Regime for
 upland and wetland areas as soil moisture allows            A landowner’s Guide to prairie management in Minnesota,
                                                             Svedarsky, W.D., M.A. Kuchenreuther, G.J. Cuomo, P. Buesseler,
 Year 1         Mow (6-8 inches) – every 30 days after       H. Moechnig, and A. Singh.
                planting until September 30; spot spray
                                                             Going Native, A prairie restoration handbook for Minnesota land-
                thistle and other problematic weeds.
                                                             owners, Fuge.

 Year 2         Mow (6-8) inches one time between June       The Tallgrass Restoration Handbook for Prairies, Savannas, and
                1 – August 15 before weeds set seed.         Woodlands, Packard, S., Mutel, C.F.
                Conduct additional mowing as needed.
                                                             Restoring Canada’s Native Prairies: A Practical Manual, Morgan,
                                                             J.P., Collicutt, D.R. and Thompson.
 Year 3         Spot spray perennial weeds if necessary.
                                                             Restoring the Tallgrass Prairie: An Illustrated Manual for Iowa and
 Future         Continue spot treatment of weeds and         the Upper Midwest, Shirley S.
 Maintenance    conduct burning on upland areas on a 3-5     Revegetation Practices in a Seasonal Wetland Restoration in
                year rotation.                               Minnesota, Bohnen, J.L., Galatowitsch, S.M.
                                                             Weed Control Methods Handbook, Tu, M., Hurd, C., Randall, J.(The
                                                             Nature Conservancy).
One strategy to control hybrid cattail and phragmites
involves cutting leaves close to the ground in the fall      Link to Appendix 5-B, Mowing for Establishment
or winter when water levels are low and the cutting          Specifications
can be done on the ice. When water levels rise with the
spring thaw, the air supply to the rhizomes will be elimi-
nated, killing or weakening the plant. Cutting can also
be conducted when the plants are flowering if they are
                                                             Herbicide Application for
cut below the water level (Payne, 1992). More informa-       Establishment
tion is presented on cattail control in Appendix A.
Mowing can also be used to decrease the height of            Spot treatment with herbicide is a typical practice for
vegetation before water levels are increased to remove       both upland and wetland areas to remove undesirable
undesirable plants such as reed canary grass. Mow-           perennial species that will not be controlled through
ing will decrease the amount of oxygen available to
plants through leaves and stems that extend above the
water’s surface.

Influence on Other Strategies
Mowing is most commonly used in uplands for the
establishment phase and in wetlands as conditions
allow. Mowing is used in combination with spot treat-
ment to control weeds as a project establishes. Mowing
is sometimes conducted prior to a burn as part of long-
term maintenace if fuel levels are low to help carry the
fire. Mowing may also be used in combination with
water level control to reduce vegetation height before
raising water levels to drown undesirable vegetation.

                                                             Figure 5.114 Boom Sprayer

DECEMBER 2008                                                      5  8 M A I N T E N A N C E F O R V E G E TAT I O N E S TA B L I S H M E N T   95
     mowing. Sufficient herbicide should be applied to                          Equipment/Materials
     target species to cover leaves to the extent possible.
     It is common to use broad spectrum herbicides while                        Equipment for herbicide application includes boom
     conducting spot treatment but grass specific or broad-                     sprayers mounted on trucks and tractors, backpack
     leaf specific herbicides can be used to cause less impact                  sprayers and herbicide wands.
     on non-target species. If large areas of desirable species
     are removed during spot treatment, re-seeding may be                       Typical Strategies
     necessary.                                                                 Spot Treatment - Spot spraying is an effective control
                                                                                technique for perennial invasive species that will persist
     Herbicide applications over large areas can be conduct-                    in a restoration. Timing of application and the herbicide
     ed during the establishment phase but should be well                       used will depend on the target species. In some cases,
     planned to minimize impact to non-target species.                          areas of native species may need to be sprayed at the
                                                                                same time as invasives and later reseeded. Canada
     Certain herbicides cannot be used near                                                     thistle and reed canary grass may
     water due to toxicity to aquatic organ-                                                    require mowing earlier in the season to
     isms. This is true for the grass specific                                                  prevent seed production and herbicide
     herbicides Assure II (Quizolofop P-Ethyl)                                                  application in the fall when treatment is
     or Poast/Vantage (Sethoxydim) as well                                                      most effective.
     as Roundup, a non-aquatically certified
     glyphosate product. Project specifica-                                                     Hand-held wand applicators can be
     tions and label recommendations must                                                       used for spot treatment as they allow
     be followed for herbicide application.                                                     the application of herbicide to specific
                                                                                                plants without spraying the surrounding
     The following are general guidelines for                                                   vegetation. Larger versions of wand ap-
     herbicide use:                                                                             plicators are mounted behind tractors.

         Herbicide applicators must follow                        Figure 5.115                 Grass specific herbicides are increasingly
        label recommendations                                     Backpack Sprayer             popular for cohntrolling reed canary
        Herbicide applicators must have                                                        grass during vegetation establishment.
        commercial herbicide applicators certification                          See Appendix 5-A for recommendation on their use for
                                                                                controlling reed canary grass.
         Appropriate gear should be worn according to
        label directions                                                        Effectiveness of grass specific herbicides can be in-
        Non-target species should be identified and                             creased by following label recommendations related to
        protected from application                                              time of use, surfactants, and other additives. The follow-
                                                                                ing information provides recommendations for the use
        Wind speeds should be less than 10 mph during
                                                                                of grass specific herbicides
        application to minimize drift
        In public places, notices should be posted for all                      Early Spring Spraying in Uplands – Early spring ap-
        treated areas                                                           plications of glyphosate is a strategy that is sometimes
                                                                                used in upland prairies to remove cool-season weeds
        Herbicides must be labeled appropriately
                                                                                such as Kentucky bluegrass and smooth brome. Sprays
        Herbicides must be stored appropriately                                 are conducted around early to mid-April before warm
        Herbicide containers should be thoroughly cleaned                       season prairie species are active. This strategy is most useful
        and rinse water must be disposed of according to                        in stands that are dominated with warm season grasses, as
        EPA Guidelines                                                          it will remove cool-season native grasses and forbs.

        Animals and people should be prevented if possible                      Control of Specific Invasive Species – Herbicides can
        from entering areas of recent herbicide application

96   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                                 M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
be sprayed over large areas of infestation when non-                  the Upper Midwest, Shirley S.
target species are dormant. Other herbicides specifical-              Revegetation Practices in a Seasonal Wetland Restoration in
ly target grasses or broad-leaved weeds. Spot herbicide               Minnesota, Bohnen, J.L., Galatowitsch, S.M.
application helps to control many invasive species.                   Weed Control Methods Handbook, Tu, M., Hurd, C., Randall, J.(The
                                                                      Nature Conservancy)
See the following links to Appendix 5A for herbicide                  MNDNR Invasive Species,
control information for specific invasive species.                    html

Hybrid cattail (Typha glauca)                                         Link to Appendix 5-B, Herbicide Application for Estab-
Narrow-leaf cattail (Typha angustifolia)                              lishment Specifications
Purple loosestrife (Lythrum salicaria)
Reed canary grass (Phalaris arundinacea)
Common buckthorn (Rhamnus cathartica)                                 Hand Weeding
Glossy buckthorn (Frangula alnus)
Common reed grass (Phragmites australis,
  syn. P. communis)
Canada thistle (Cirsium arvense)                                      Hand weeding is a labor-intensive technique that is not
Crown vetch (Coronilla varia)                                         cost-effective for large areas but is a viable option when
Bird’s foot trefoil (Lotus corniculatus)                              attempting to minimize herbicide use. Hand weeding
Sweet clover (Melilotus officinalis and M. alba)                      can be useful for the management of small popula-
Wild parsnip (Pastinaca sativa L.)                                    tions of invasive species and to aid the establishment of
Spotted knapweed (Centaurea maculosa)                                 competition-sensitive species.

Influence on Other Strategies                                         Equipment/Materials
Spot treatment with herbicides is a common practice to                Gloves and eye protection are typical equipment for
control invasive species within plantings. It is common-              hand weeding. Tools such as trowels and dandelion
ly conducted simultaneously with other maintenance                    diggers can be useful to loosen large roots. Tractor
strategies such as mowing, burning, and biological                    mounted platforms have been developed to increase
control. Some species such as Canada thistle and reed                 hand weeding efficiency.
canary grass may require mowing earlier in the season
to prevent seed production and herbicide application
in the fall when treatment is most effective and other
species are dormant.

A landowner’s Guide to Prairie Management in Minnesota, Sve-
darsky, W.D., M.A. Kuchenreuther, G.J. Cuomo, P. Buesseler, H.
Moechnig, and A. Singh.
Going Native, A Prairie Restoration Handbook for Minnesota
lLndowners, Fuge

The Tallgrass Restoration Handbook for Prairies, Savannas, and
Woodlands, Packard, S., Mutel, C.F.

Restoring Canada’s Native Prairies: A Practical Manual, Morgan,
J.P., Collicutt, D.R. and Thompson.
Restoring the Tallgrass Prairie: An Illustrated Manual for Iowa and

                                                                      Figure 5.116

DECEMBER 2008                                                               5  8 M A I N T E N A N C E F O R V E G E TAT I O N E S TA B L I S H M E N T   97
     Typical Strategies                                                 Hydrology Control for Vegetation
     Efforts should be made to avoid the disruption of the              Establishment
     soil during weeding, which could provide conditions
     for the establishment of additional weeds or invasive              Overview
     species. Weeding should be conducted when the soil is
                                                                        Water control structures play an important role in the
     moist because the weeds are much easier to pull and it
                                                                        management of open water wetlands. Appropriate
     will cause less disruption to the surrounding soil. Weed-
                                                                        water level management can promote the establish-
     ing is beneficial in wetlands where young cattail plants
                                                                        ment and growth of desirable plants and discourage
     are invading an area. If cattails can be pulled before ex-
                                                                        the establishment of undesirable species. Water control
     tensive rhizomes have developed, their establishment
                                                                        structures allow for managing shallow water or moist
     can be slowed or prevented. Weeding successively, in
                                                                        soil conditions during the vegetation establishment pe-
     conjunction with the establishment of populations of
                                                                        riod and can help prevent wetland seed from floating
     native vegetation, will often control cattail invasions
                                                                        to the surface and moving to the water’s edge in a
     (Hild 1999). Weeding is also effective for eradication of
     small populations of invasive species. In the case of pur-
     ple loosestrife, plants can be pulled out of the ground
     when they are young. Older plants develop dense root
     systems, making them difficult to pull.

     Tartarian honeysuckle and buckthorn can be removed
     by pulling with weed wrenches, tools specifically
     designed for pulling invasive shrubs. When using weed
     wrenches, it is recommended to lop the shrubs at
     waist height before pulling so that branches will not
     be directed toward the face. Gloves and eye protection
     should be worn. After shrubs are removed, their roots
     should be shaken to remove any soil and disturbed soil
     should be tamped by foot to prevent the germination
     of weeds or more invasive shrubs.

     Influence on Other Strategies
     Hand weeding is conducted on small sites where the                 Figure 5.117 In-line Water Control Structure
     pulling of weeds is practical. Hand weeding can be
     done in combination with mowing, spot spraying, and                narrow band. With the use of water control structures,
     biological control.                                                seed will tend to stay in place and cover the bottom
                                                                        of the wetland instead of just the fringe (Hoag 2000).
     Resources                                                          Water control structures can aid in the establishment of
                                                                        sedge and wet meadow communities by maintaining
     Going Native, A Prairie Restoration Handbook for Minnesota         saturation near the ground surface. Water control struc-
     lLndowners, Fuge
                                                                        tures can also help control invasive species by allowing
                                                                        for the drainage of open water and the subsequent
     Weed Control Methods Handbook, Tu, M., Hurd, C., Randall, J.(The
     Nature Conservancy).
                                                                        use of non-aquatically certified herbicides. See Section
                                                                        4, Project Engineering Design and Construction for
     Link to Appendix 5-B, Hand Weeding Specifications                  information on water control structures.

                                                                        Water control structures or phased hydrology

98   S E C T I O N 5 V E G E TAT I O N E S TA B L I S H M E N T                       M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
Typical Strategies                                           the design phase of the
                                                             project to ensure the
The most successful wetland plant establishments,            project goals, objectives
whether through the use of native seedbank in the soil       and site constraints are
substrate, supplemental wetland seedings, plantings,         clearly understood by all
occur when the most suitable hydrologic conditions are       involved in
present in the wetland. For most wetland plant species,      the project.
these conditions are achieved by establishing shallow
water or a moist soil environment as these plants are        The timing of the
germinating and growing. Care must be taken dur-             wetland plantings also
ing the initial establishment of these wetland species       needs to be coordinated
to avoid deep water conditions or flooding, as plant         with the return or intro-
growth will be inhibited by these conditions. Many           duction of hydrology         Figure 5.119
undesirable plant species such as reed canary grass and      to the site. This requires
narrow-leaf cattail will thrive under these conditions as    coordination with the project engineers. The planned
they are best adapted to sites with high water level fluc-   construction schedule needs to be understood to
tuations. Many native wetland plants, including most         ensure that the planned strategies for wetland vegeta-
sedge species, will not tolerate rapid water fluctuations.   tion establishment will be successful. For example, the
                                                             return of hydrology to a wetland restoration project can
Conversely, if the soils are kept too dry, invasive or       occur immediately after construction is completed and
other undesirable species will survive and compete           if the planned seedings or plantings of wetland veg-
with desired vegetation, reducing growth rates and           etation have not been completed, site conditions may
inhibiting spreading and colonization. The objective is      prevent that work from occurring if drawdown capabili-
to eliminate invasives and other undesirable species by      ties are not available to the project.
flooding, while not stressing desirable wetland species
from deep flooding. Careful and precise water level          Wetland hydrology is best managed through the use of
management is important for successful establishment         water control structures. Unfortunately, site conditions
of vigorous stands of emergent wetland species (Ham-         and project budgets often prohibit their use on every
mer 1992).                                                   project. When water level management through the
                                                             use of control structure is not available, other strate-
When the project goal is to achieve a high level of          gies for management need to be considered. This can
wetland plant diversity, success is usually best achieved    include staging of construction activities in an attempt
when hydrology is adequately managed in terms of             to introduce hydrology to the wetland in phases. For
both controlling the wetland “bounce” after runoff           example, temporary wetland outlets that are set lower
events and controlling water levels through manipula-        in elevation than the planned final outlet structure can
tion of the planned outlet structure. Personnel respon-      be installed or utilized during the first season that veg-
sible for establishing and managing wetland vegetation       etation is being established. Upon successful germina-
need to coordinate with the project engineers early in       tion and growth of the wetland vegetation, the work on
                                                             constructing the final outlet can be completed.

                                                             If water control structures have been installed, water
                                                             levels can be raised periodically to inhibit invasive
                                                             species. Water levels should not be raised over the
                                                             height of the seedlings. Water levels can gradually be
                                                             increased as plant height increases. As plants reach a
                                                             height of one to two feet in saturated soil, water levels
                                                             should be raised a few inches for bulrushes, broad-
                                                             leaved arrowhead, plantains, smartweeds, spikerushes,
                                                             pickerelweed and arum. This increased water level is
Figure 5.118 Establishing Vegetation

DECEMBER 2008                                                     5  8 M A I N T E N A N C E F O R V E G E TAT I O N E S TA B L I S H M E N T   99
      important because many wetland plants rely on buoy-                      Submersion of vegetation should
      ant structures and water pressure for physical support                   be avoided in combination with
      to grow in an upright manner (Hammer, 1992). Ulti-                       biological control to ensure that
      mately, water levels should be managed to maintain                       biological control agents are not
      the target plant community. Fluctuating water levels                     eliminated from the site.
      mimic natural wetlands, which seldom have a constant
      water level (Hoag, 2000).                                                Resources
                                                                               Effects of Water Regime and Competition on the
      Managers need to experiment with water levels to
                                                                               Establishment of a Native Sedge in Restored Wetlands.
      understand soil and water characteristics, patterns of
                                                                               Budelsky, R., Galatowitsch, S.
      water availability, seed stocks, response of vegetation,
                                                                               Establishment of Carex stricta Lam. Seedlings in experimen-
      and chronology of wildlife use (Payne, 1992). Creating
                                                                               tal wetlands with implications for restoration. Budelsky R.,
      a diversity of plant and animal life is a primary goal
                                                                               Galatowitsch, S.
      of water level manipulation. Wildlife species such as
                                                                               Factors Affecting Revegetation of Carex lacustris and Carex stricta
      waterfowl will benefit. For example, draw downs of
                                                                               from Rhizomes, Yetka, L., Galatowitsch, S.
      Minnesota wetlands are conducted to promote emer-
      gent vegetation use by breeding waterfowl. In addition,                  Techniques for Wildlife Habitat Management of Wetlands
                                                                               (Payne 1992)
      in southern areas, draw downs are used to promote the
      growth of annuals that are a food source for migrating
      ducks and geese.                                                         Link to Appendix 5-B, Water Level Management
      Influence on Other Strategies
       Table 5.25 Typical schedule for water level
       control to establish emergent vegetation
       April                             Seeding and installation of wet-      Most new plantings need approximately one inch of
                                         land plugs along open water fringe    water a week from rainfall or other methods. The most
                                                                               efficient method of watering involves taking advantage
       Early June (once seed-            Raise water level 1 inch (water
                                                                               of rainfall around the time of planting. In some cases,
       lings reach 6 inches)             levels should not be raised over
                                         the top of establishing vegetation)   water control structures can be used to retain rainfall. If
                                                                               water control structures are not available, other options
       One week later                    Lower water level to the ground       may include water trucks, pumps, and irrigation.
       15-20 days later                  Raise water level 1 inch              Water control structures, Water trucks, Pumps and
       One week later                    Lower water level to the ground
                                                                               Typical Strategies
       As plants reach a                 Raise water levels 3-4 inches
                                                                               Care should be taken when using water control struc-
       height of 1-2 feet
                                                                               tures to not drown new seedlings. In cases where water
       Future management                 Fluctuate water levels to mimic       control structures are not available, watering can be
                                         natural variations                    conducted with water trucks, pumps, and various types
                                                                               of irrigation. For very large sites, these methods may
      *Note: Water levels should not be raised over the top of estab-
                                                                               not be practical. If watering will not be possible for a
      lishing vegetation. This strategy can work well along the open
      water fringe once all planned vegetation is establishing or if           project, it is beneficial to plant in the fall, winter, or early
      primarily plugs are planted. If later successional species are           spring so that soil moisture will be high during estab-
      expected, such as in sedge meadow plantings, saturation near
      the surface should be maintained.

100 S E C T I O N 5   V E G E TAT I O N E S TA B L I S H M E N T                                 M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E
lishment. Trees and shrubs can be planted success-
fully in the fall as late as November, maximizing early
spring soil moisture. Planting containerized plants and
rootstock can sometimes be done as early as March if
plant material is available. Plantings can be planned to
coincide with rainfall.

Influence on Other Strategies
Planting dates can be adjusted to take advantage of
natural moisture to maximize planting success if water-
ing will not be possible.

Irrigation Systems for Restoration & Mitigation Sites, Alexander, B.

Link to Appendix 5-B, Watering Specifications

                                                                       Figure 5.121

Figure 5.120

DECEMBER 2008                                                              5  8 M A I N T E N A N C E F O R V E G E TAT I O N E S TA B L I S H M E N T   101
      Figure 5.122                                                 Figure 5.123

      Figure 5.124

102 S E C T I O N 5   V E G E TAT I O N E S TA B L I S H M E N T                  M I N N E S O TA W E T L A N D R E S T O R AT I O N G U I D E