Wet Silty Floodplain

Description

Historically these sites were influenced by flooding, wind damage, ice storms, and grazing by native species. The historic reference state for this ecological site was an old-growth riverine deciduous forest. American elm (Ulmus americana) was a key species. Sites were disturbed periodically via flooding but the overall, these communities were stable, diverse, and long-lived.

The reference state is a mature floodplain deciduous mixed forest with multiple co-dominant species. Common trees include green ash, American elm, American sycamore, silver maple, sweetgum, pin oak and hackberry. Sites with only occasional flooding may include bur oak (Quercus macrocarpa), shingle oak (Quercus imbricaria), and pecan (Carya illinoinensis). Vegetative community composition is dependent on flooding and microtopography.

Shrubs commonly include possumhaw (Ilex decidua), dogwood (Cornus spp.), and hawthorn (Crataegus spp.). The herbaceous layer on these sites is diverse and often dense. Species include bedstraws (Galium spp.), violets (Viola spp.), sedges (Carex spp.), smallspike false nettle (Boehmeria cylindrica), Canadian woodnettle (Laportea canadensis), and touch-me-not (Impatiens spp.).

Dominant plant species

1. American elm (Ulmus americana), tree

2. green ash (Fraxinus pennsylvanica), tree

3. dogwood (Cornus), shrub

4. hackberry (Celtis), shrub

5. sedge (Carex), grass

6. Canadian woodnettle (Laportea canadensis), grass

Submodel

Description

Most remaining Wet Silty Floodplain sites have been altered due to disturbances and hydrological modifications, either within the watershed, or upstream. Dams, ditching, tiling, levees, and urban, industrial and agricultural impacts are common and have modified the historic natural riparian processes. Trees on disturbed sites will depending on the type, length and severity of disturbances. Hydrological modifications may have altered drainage on these sites. Common species including ash, maple, poplar, sweetgum, and hackberry.

Disturbance may introduce non-native plant species to these sites and without management control, these invasive plants will fundamentally alter the plant community. Many of these sites are transitioned to Pastureland (State 3) or cropland (State 4).

Dominant plant species

1. silver maple (Acer saccharinum), tree

2. hackberry (Celtis), tree

3. green ash (Fraxinus pennsylvanica), tree

4. sweetgum (Liquidambar styraciflua), tree

5. dogwood (Cornus), shrub

6. black elderberry (Sambucus nigra), shrub

7. sedge (Carex), grass

8. Canadian woodnettle (Laportea canadensis), grass

Submodel

Description

A portion of these sites have been converted to pastureland or forage production. Species selection will depend upon the objectives and goals of the landowner; however, commonly planted grasses include tall fescue (Schedonorus arundinaceus), brome (Bromus spp.), white clover (Trifolium repens) and red clover (Trifolium pratense). Species health and productivity are determined by the management. Hydrological modifications such as ditching and/or tiling may be installed to improve drainage.

Dominant plant species

1. tall fescue (Schedonorus arundinaceus), grass

2. brome (Bromus), grass

3. Kentucky bluegrass (Poa pratensis), grass

4. white clover (Trifolium repens), grass

5. red clover (Trifolium pratense), grass

Submodel

Description

Hydrological modifications such as ditching and tiling are often used on these sites to increase crop production. Common crops include corn (Zea mays), soybeans (Glycine max), and occasionally winter wheat (Triticum aestivum). Some landowners choose to convert sites to cool season grasses for a period before resuming cropland production.

A return to the historical Reference State from State 4 is unlikely, if not impossible.

Dominant plant species

1. corn (Zea mays), grass

2. soybean (Glycine), grass

Submodel