Vegetation Classification and Mapping Project Report - USGS

USGS-NPS Vegetation Mapping Program
Colonial National Historical Park
COMMON NAME (PARK-SPECIFIC): DISTURBED TIDAL HARDWOOD SWAMP
SYNONYMS
USNVC English Name: Not Applicable
USNVC Scientific Name: Not Applicable
USNVC Identifier: Nonstandard
LOCAL INFORMATION
Environmental Description: Disturbed Tidal Hardwood Swamp includes formerly tidal
wetlands that have been cut off from all or most of their tidal influence, either by roads or berms.
The hydrology is now semipermanently flooded. These wetlands may periodically be flooded by
storm surge and can have somewhat oligohaline waters. Most examples have sustained heavy
wind damage from past hurricanes.
Vegetation Description: Disturbed Tidal Hardwood Swamp has an open deciduous canopy
with 25-50% cover dominated by Acer rubrum (red maple), sometimes with Pinus taeda
(loblolly pine), Nyssa biflora (swamp tupelo), and Liquidambar styraciflua (sweetgum). Fallen
and standing dead trees are common. Shrub dominants are Morella cerifera (wax myrtle) and
Persea palustris (swamp bay). Other shrubs include Baccharis halimifolia (eastern baccharis)
and Cornus foemina (stiff dogwood). Decodon verticillatus (swamp loosestrife), a suffrutescent
(shrubby) herb, can be a patch dominant. Vines are common and include Mikania scandens
(climbing hempvine), Smilax rotundifolia (roundleaf greenbrier), Toxicodendron radicans
(eastern poison ivy), and Vitis rotundifolia (muscadine). Areas of deep water may have floating
aquatic plants such as Lemna minor (common duckweed). A variety of wetland plants may be
found in the herb layer: rooted aquatic plants such as Hydrocotyle verticillata var. verticillata
(whorled marshpennywort), Murdannia keisak (wartremoving herb), Pontederia cordata
(pickerelweed), Typha angustifolia (narrowleaf cattail), and Typha latifolia (broadleaf cattail);
many wetland grasses and grasslike plants such as Carex crinita (fringed sedge), Carex
hyalinolepis (shoreline sedge), Cinna arundinacea (sweet woodreed), Elymus virginicus var.
halophilus (Virginia wildrye), Juncus effusus (common rush), Leersia virginica (whitegrass), and
Panicum virgatum var. virgatum (switchgrass); as well as other plants of mesic to wet habitats,
including Polygonum arifolium (halberdleaf tearthumb), Polygonum punctatum (dotted
smartweed), Teucrium canadense (Canada germander), and Thelypteris palustris var. pubescens
(eastern marsh fern).
Most Abundant Species:
Stratum Lifeform Species
Tree canopy Broad-leaved deciduous tree Acer rubrum (red maple)
Shrub/sapling (tall & short) Broad-leaved deciduous shrub Morella cerifera (wax myrtle)
Herb (field) Graminoid Typha latifolia (broadleaf cattail)
Characteristic Species: Acer rubrum (red maple), Morella cerifera (wax myrtle), Murdannia
keisak (wartremoving herb), Typha latifolia (broadleaf cattail).
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 Tidal Hardwood Swamp is mapped as three polygons on Jamestown
Island, covering a total of 4.6 hectares (11.4 acres). Small areas below minimum mapping unit
may occur as inclusions in the surrounding landscapes.
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