Vegetation Classification and Mapping Project Report - USGS

USGS-NPS Vegetation Mapping Program
Colonial National Historical Park
COMMON NAME (PARK-SPECIFIC): DISTURBED SEEPAGE SWAMP
SYNONYMS
USNVC English Name: Not Applicable
USNVC Scientific Name: Not Applicable
USNVC Identifier: Nonstandard
LOCAL INFORMATION
Environmental Description: Disturbed Seepage Swamp is a forested wetland with saturated
hydrology. These forests have developed in areas where the natural hydrology has been altered
by impoundments or roads. In Colonial National Historical Park, this map class is found where
the Colonial Parkway bisects former bottomlands or in the upper reaches of impounded ravine
systems where exotic plants have invaded the ravine bottoms.
Vegetation Description: Disturbed Seepage Swamp may occur as a well-formed forest or as
dense regeneration of hardwood trees. The canopy is typically dominated by Acer rubrum (red
maple) with associates such as Platanus occidentalis (American sycamore), Liquidambar
styraciflua (sweetgum), or Fraxinus pennsylvanica (green ash). Shrubs are variable but can
include Asimina triloba (pawpaw), Salix nigra (black willow), and Liquidambar styraciflua
(sweetgum). The herb layer is often dominated by Leersia virginica (whitegrass) or the exotic
grass Microstegium vimineum (Nepalese browntop). Other characteristic herbs include
Boehmeria cylindrica (smallspike false nettle), Cardamine pensylvanica (Pennsylvania
bittercress), Cinna arundinacea (sweet woodreed), Circaea lutetiana ssp. canadensis (broadleaf
enchanter's nightshade), Hedera helix (English Ivy), Impatiens capensis (jewelweed), Saururus
cernuus (lizard's tail), Packera aurea (golden ragwort), and Woodwardia areolata (netted
chainfern).
Most Abundant Species:
Stratum Lifeform Species
Tree canopy Broad-leaved deciduous tree Acer rubrum (red maple)
Herb (field) Graminoid Microstegium vimineum (Nepalese browntop)
Characteristic Species: Acer rubrum (red maple), Microstegium vimineum (Nepalese
browntop).
Other Noteworthy Species: Information not available.
Subnational Distribution with Crosswalk Data:
State SRank Rel Conf SName
Reference
VA
NA . .
[not crosswalked, not ranked] .
Local Range: Disturbed Seepage Swamp is mapped along Colonial Parkway near Papermill
Creek and in Yorktown and in the upper reaches of Yorktown Creek ravines.
Classification Comments: Forests mapped as Disturbed Seepage Swamp may have formerly
been Coastal Plain Calcareous Seepage Swamp or other seepage wetlands, but now have a
species composition too altered to assign them a natural community classification.
Other Comments: Information not available.
Local Description Authors: K. D. Patterson.
Plots: None.
Colonial National Historical Park Inventory Notes: Information not available.
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