Bedrock Floodplain Forest (Central Appalachian-Piedmont)

Park specific natural communities coming soon.

The Bedrock Floodplain Forest is found alongside the Potomac River on floodplains where the bedrock is at or very near the surface. The plants that grow here, such as green ash trees, must be able to tolerate the disturbance that occurs when the river is high. (There is more than one type of Bedrock Floodplain Forest; this one is found in the Central Appalachians and Piedmont.)

This natural community is restricted to the Ridge and Valley and Piedmont sections of the Potomac River floodplain, where it occurs on floodplains where bedrock is at or very near the surface.

The range map shows the states in which this natural community has been documented.

More About This Natural Community

Located on floodplains along the Potomac River, this natural community is typically flooded annually, and standing water may be present for weeks at a time. Floods scour the surface, often removing what little soil might have accumulated on the bedrock. On the other hand, floods can also sometimes deposit sediment, which contains minerals and nutrients that help plants grow.

The trees that eke out a living here are typically stunted and often widely spaced. Among these, green ash is usually the most common. Other species might include silver maple, American sycamore, American elm, river birch, box-elder, black willow, eastern cottonwood, and black walnut.

Shrubs are uncommon, but there may be vines of eastern poison-ivy, Virginia creeper, riverbank grape, and frost grape.

For a more in-depth look at this community, click on a link under “Where to Explore It.”

Look for It in These National Parks

  • Chesapeake and Ohio Canal National Historical Park
  • George Washington Memorial Parkway
  • Harpers Ferry National Historical Park 

Conservation Status

How vulnerable is a natural community? Is it at risk of elimination? Learn about conservation status.

Global Conservation Status: 
G2? – Imperiled? (Status uncertain)


Official names reduce confusion by providing a common language for talking about natural communities. Why so many names?

Common Name: 
Bedrock Floodplain Forest (Central Appalachian-Piedmont)
Scientific Name Translated: 
American Sycamore - Silver Maple - Green Ash / Small-spike False Nettle - Emory's Sedge Floodplain Forest
Classification Code: