4.4 Terrestrial Communities
• Close sensitive areas at certain times (e.g., during Timber Rattlesnake emergence or Peregrine Falcon nesting) or permanently to stop direct trampling, loss of habitat to recreation developments, trails, vistas, etc., and indirect human impacts (disturbance).
4.4.8 Low Elevation Flatrocks, Cliffs, and Rock Outcrops 4.4.8.1 Ecosystem Description
Tis broad ecosystem group encompasses many, though not all, of the community types at low to mid-elevations that are too steep or rocky to support a closed tree canopy. Te veg- etation of these communities is generally very patchy, refecting extreme variability in the depth and composition of soil and of available moisture. Plants include forest species with broad site tolerances, species characteristic of a wide range of open habitats, and species specialized for rock outcrops. Rock outcrops typically are very dry, but seepage zones are often present and may support wetland vegetation. Tis community type generally occurs below 2,000 feet in elevation. In contrast, mid-elevations range from 2,000 to 4,000 feet and high elevations are above 4,000 feet. Te nine natural clif and rock outcrop community types are separated based on rock chemistry, topographic location, and geographic region, and the latter is an important factor in determining fora. Te community types are: Piedmont/Coastal Plain heath blufs and acidic clifs; Piedmont mafc and calcareous clifs; montane mafc, calcareous, and acidic clifs; and low-elevation granitic domes and rocky summits. • Low-elevation rocky summit communities occur in exposed positions on peaks, ridge- tops, and upper slopes in the Mountain ecoregion. Low-elevation rocky summits have fractured rock which allows growth of deep-rooted woody plants in places. Soil accu- mulates in pockets of varying depth and produces heterogeneous vegetation. Many variants potentially occur, but are not well known. • Low-elevation granitic domes occur on exfoliated outcrops of granitic rock, where peeling of sheets of rock parallel to the surface produces a dome-shaped outcrop of solid rock. Soil mats that begin as moss clumps gradually thicken over time and follow a characteristic vegetational succession from herbs to shrubs and stunted trees. Te unanchored mats are periodically destroyed by falling of or by being pulled up by fall- ing trees, leaving the rock bare and beginning the succession anew. • Clif communities occur on lower, more sheltered topographic sites. Tey are generally created by streams undercutting a bluf, but may occur somewhat above a stream. Like rocky summits, the rock is usually fractured and supports very patchy vegetation that includes woody plants rooted in crevices, as well as herbs in soil pockets, and mosses and lichens on bare rock. Te Mountain and Piedmont/Coastal Plain types have fora
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2015 NC Wildlife Action Plan
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