Vegetation Classification and Mapping Project Report - USGS

USGS-NPS Vegetation Mapping Program
Colonial National Historical Park
where incising streams drain "piedmont" landforms at the foot of Ridge and Valley strike ridges
(Harbor 1996). Slopes of plot-sampled stands range from 1-13 degrees (mean = 6 degrees), with
aspects essentially flat to westerly. Soils of these sites are deep, very oligotrophic, gravelly loams
with low pH and base status. Exposed rocks of any kind (outcrops, boulders, or stones) are
usually sparse to absent. Most sites appear to have a history of fires.
Vegetation Description: The vegetation is a closed to very open oak forest with mixed and
variable canopy dominance by Quercus alba (white oak), Quercus coccinea (scarlet oak), and
Quercus prinus (chestnut oak). Various Pinus spp. (pines), including Pinus virginiana (Virginia
pine), Pinus echinata (shortleaf pine), Pinus strobus (eastern white pine), and Pinus rigida (pitch
pine), are frequent overstory associates, particularly following fire or logging disturbances.
Quercus falcata (southern red oak), Quercus stellata (post oak), Carya glabra (pignut hickory),
and Carya alba (mockernut hickory) are infrequent canopy trees. Nyssa sylvatica (blackgum),
Amelanchier arborea (common serviceberry) and, in the southern part of the range, Oxydendrum
arboreum (sourwood) attain exceptional abundance and stature in these forests, dominating the
subcanopy layers and occasionally reaching the overstory. Acer rubrum (red maple) and
Sassafras albidum (sassafras) are other common understory trees. The shrub layer is typically
dominated by deciduous ericaceous species, with Gaylussacia baccata (black huckleberry),
Vaccinium pallidum (Blue Ridge blueberry), and/or Vaccinium stamineum (deerberry)
consistently forming dense colonies. Less abundant or constant shrubs and vines include
Castanea pumila (chinkapin), Quercus ilicifolia (bear oak), Kalmia latifolia (mountain laurel),
Rhododendron periclymenoides (pink azalea), Lyonia ligustrina (maleberry), Vaccinium
stamineum (deerberry), Smilax glauca (cat greenbrier), Smilax rotundifolia (roundleaf
greenbrier), and Cornus florida (flowering dogwood). Despite high shrub densities, a number of
low-cover herbs and subshrubs occur in the type, including Chimaphila maculata (striped
prince's pine), Isotria verticillata (purple fiveleaf orchid), Uvularia puberula (mountain
bellwort), Epigaea repens (trailing arbutus), Pteridium aquilinum var. latiusculum (western
brackenfern), Cypripedium acaule (moccasin flower), Gentiana villosa (striped gentian),
Comandra umbellata (bastard toadflax), Angelica venenosa (hairy angelica), and Iris verna
(dwarf violet iris). Mean species richness of 54 Virginia, Maryland, and District of Columbia
plot samples is 25 taxa per 400 square meters.
Most Abundant Species: Information not available.
Characteristic Species: Amelanchier arborea (common serviceberry), Castanea pumila
(chinkapin), Gaylussacia baccata (black huckleberry), Isotria verticillata (purple fiveleaf
orchid), Nyssa sylvatica (blackgum), Oxydendrum arboreum (sourwood), Quercus alba (white
oak), Quercus coccinea (scarlet oak), Quercus prinus (chestnut oak), Quercus velutina (black
oak), Rhododendron periclymenoides (pink azalea).
Other Noteworthy Species: Information not available.
USFWS Wetland System: Not applicable.
DISTRIBUTION
Range: This community is a matrix forest of dry, nutrient-poor uplands of the Mid-Atlantic
Piedmont Plateau, occurring locally in similar low-elevation landscapes of the northern Blue
Ridge and Ridge and Valley provinces of the Central Appalachians, and the Cumberland Plateau
in Tennessee. In Maryland and northern Virginia, the type also occurs on uplands of the
dissected Inner Coastal Plain. The type is well-documented through quantitative analysis in
Virginia, and qualitatively in Maryland, but probably also occurs at similar sites in West Virginia
and Pennsylvania.
229