Chapter 4 Habitats
4.4.9 Low Elevation Flatrocks, Cliffs, and Rock Outcrops 4.4.9.1 Ecosystem Description
Classification of the Natural Communities of North Carolina, Fourth Approximation (Schafale 2024) describes this natural community as Low Elevation Cliffs and Rock Outcrops Theme. This 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. The vegetation of these communities is generally very patchy, reflecting 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. This 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.
There are numerous community subtypes included in this community description.
• Coastal Plain Cliff • Low Elevation Granitic Dome • Low Elevation Rocky Summit (Acidic, Basic, Quartzite subtypes) • Montane Cliff (Acidic, Mafic, Calcareous subtypes) • Piedmont Cliff (Acidic, Basic subtypes) • Talus Vineland
Low elevation rocky summit communities occur in exposed positions on peaks, ridgetops, 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 accumulates in pockets of varying depth and produces heterogeneous vegetation. Many variants potentially occur but are not well known. Low elevation granitic domes occur generally below 3,000 feet elevation 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. The unanchored mats are periodically destroyed by falling off or by being pulled up by falling trees, leaving the rock bare and beginning the succession anew. Cliff communities occur on lower, more sheltered topographic sites and include Montane, Piedmont, and Coastal Plain subtypes. Montane cliffs are steep-to-vertical, sparsely vegetated rock outcrops on river bluffs, lower slopes, and other topographically sheltered locations. In general, they are created by streams undercutting a bluff but may occur somewhat above a
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2025 NC Wildlife Action Plan
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