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Some Major Plant
Communities of the Blue Ridge, adapted
from Woody Plants of the Blue Ridge by Ron Lance. Used by permission.
Forested Communities:
Oak-dominated
forests: Northern red oak forest: Middle to high elevation exposed
sites; canopy mostly of northern red oak.
Chestnut oak
forest: On ridge tops and steep, rocky, acidic slopes up to about
4000'; canopy mostly of chestnut oak or scarlet oak. White oak forest:
On broad ridges or flats over 3500', or lower areas of similar topography;
canopy dominated by white oak.
Mixed oak forest:
Low and middle elevations; also called montane oak-hickory, but hickory
component not reliably dominant. A common forest type of white and red
oaks, frequently with maple, hickory, blackgum, pine, and sourwood associated.
Pine-oak-heath
forest: On low peaks, knobs, steep, exposed slopes; xeric sites
susceptible to fire; canopy of yellow pines and oak, especially scarlet
oak; understory of acid-loving heath shrubs.
Mixed hardwood
forests:
Northern hardwood
forest: On high elevation slopes and coves; canopy of birch, beech,
buckeye, basswood, maple, cherry, ash, spruce; soils acidic but moist.
Rich cove forest:
On sheltered slopes and coves of lower to middle elevations; soils deep
and higher in pH; canopy diverse, with ash, basswood. sugar maple, buckeye,
magnolia, tuliptree, hickory, oak, beech, cherry; understory shrub and
herb layer diverse, devoid of large quantities of ericads.
Acidic cove forest:
On sheltered slopes and coves, gorges and ravines; canopy heavy in oak,
tuliptree, birch, red maple, hemlock, silverbell, or Fraser magnolia;
less diversity of mesophytic trees; shrub layer often dense, of rhododendron
and dog-hobble; herbaceous layer not as diverse as in rich coves.
Alluvial forest:
On low elevation bottomlands subject to occasional flooding; canopy
often with some mesophytic trees typical of cove forests, but also containing
sycamore, river birch, boxelder, willow; shrub layer often with hazelnut,
cane.
Basic mesic forest:
On low elevation slopes and coves over limestone, dolomite, or marble;
a high pH favors canopy species such as chinkapin oak, ash, sugar maple,
hackberry, elm, walnut. This forest is not common in the Blue Ridge.
It is characteristic of much of the Ridge and Valley and Cumberland
Plateau provinces.
Conifer-dominated
forests:
Spruce-fir forest:
Generally over 5500' elevation; canopy dominated by red spruce, with
some northern hardwood species present; shrubby layer of mountain-ash,
mountain maple, serviceberry, yellow birch; now generally replacing
former Fraser fir forests of highest elevations, due to elimination
of much of the fir.
Hemlock forest:
On slopes and coves where soils are acidic; canopy mostly of grove-like
stands of hemlock. Carolina hemlock usually occurs on steep slopes,
bluffs, and gorges where soils tend to be drier than with Eastern hemlock
forests.
White pine forest:
Mostly caused by man's activities; purely natural stands associated
with very steep slopes and gorges.
Pine-oak-heath
forest: As mentioned above as to species; more pine is seen in canopy
when recent fires have killed back the oak and hardwood component, favoring
seedling regeneration of pitch, shortleaf, table mountain, or Virginia
pines.
Thinly-forested
or Shrub-dominated Communities:
Swamp forest/bog
complex: On poorly drained bottoms; canopy fairly open, with hemlock,
red maple as most dominant members. Higher elevation sites may show
red spruce as canopy member. Boggy vegetation occurs below canopy and
in openings within this predominantly forested community.
Southern Appalachian
bog: Sphagnum-dominated boggy areas generally over 1 acre in size;
more open and with only a few small trees.
Shrub bald:
On exposed slopes, ridges, and peaks of middle to higher elevations:
rhododendron and/or kalmia may form dense thickets called "laurel
slicks" or "rhododendron hells," or sites may be more
open, composed of other shrubby species. Such open stands are often
successional stages of former grassy balds or of former forested areas.
Grassy bald:
On high slopes, ridgetops and domes; dominant vegetation of herbaceous
nature, mostly grasses and sedges. Woody plants encroach if this community
is protected from fire and grazing.
Boulderfields:
On high, steep, north-facing coves; angular boulders and rockpiles covered
by little soil, thought to be relicts of periglacial action; mountain
maple, yellow birch, basswood, buckeye, and gooseberry are the woody
species commonly present, though usually dwarfed.
Rock outcrops:
At all elevations, though most frequent at higher elevations; the species
of plants present on each outcrop varies with the type of rock substrate
and condition of its surface, as well as elevation. Some outcrops are
the chief habitat for many rare species of herbaceous plants.
Ref: Schafale,
M., and A. Weakley. 1990. Classification of the Natural Communities of
North Carolina; Third Approximation. Natural Heritage Program, Division
of Parks and Recreation, NC Dept. of Environment, Health, and Natural
Resources.
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