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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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