Chapter 4 Habitats
4.4.8 High-Elevation Cliffs and Rock Outcrops 4.4.8.1 Ecosystem Description
Classification of the Natural Communities of North Carolina, Fourth Approximation (Schafale 2024) has updated this natural community as High Elevation Rock Outcrops Theme. High-elevation rock outcrops are extremely rare, have a very restricted range, and are subject to extreme environmental conditions . These communities occur on ridge tops, peaks, and upper slopes where soils are thin and discontinuous and rock dominates the surface. Even in the most rugged high Mountains, they represent only a small minority of the landscape, generally at 4,000 feet in elevation and higher. In contrast, mid-elevations range from 2,000 to 4,000 feet and low elevations are below 2,000 feet. The vegetation is likely to be very patchy, reflecting the variability of the soil.
There are six community subtypes in this ecosystem.
• High Elevation Granitic Dome • High Elevation Rocky Summit (Typic, High Peak, Little Bluestem Basic, Ninebark Basic, High Peak Lichen subtypes) High elevation granitic domes occur on the exfoliated outcrops that form when massive granitic rock breaks off in sheets parallel to the surface. Exfoliation produces smooth dome-shaped outcrops that lack crevices. Lichens and mosses occur on the bare rock. Soil and vegetation develop together on the rock surface as moss mats gradually deepen and are invaded by a succession of herbs. Soil mats are not anchored to the rock below and eventually fall off or are pulled up by falling trees, leaving the rock bare again. The shallow soils are generally dry, but some zones of seepage are usually present on the edge of the soil of adjacent forests. A number of wetland plants can occur in these saturated areas. They have shallow soils and occur on fractured rock. The bare rock is similarly vegetated by patches of lichen and moss, and shallow soil mats may develop locally. The presence of fractures, however, offers patches of deeper, more permanent soil that can support deeper rooted plants, and can provide an opportunity to anchor soil mats. The vegetation pattern is less likely to shift over time. 4.4.8.2 Location of Habitat High-elevation cliffs and rock outcrops occur only in the highest mountain ranges within the Mountain ecoregion in the Great Smokies, Plott Balsams, Great Balsams, Black/Craggy Mountains, Grandfather Mountain, Roan Mountain, and in the Amphibolite Mountains of Ashe County. According to the most recent Southeast GAP analysis, rocky summit and granitic domes comprise approximately 1,696 acres (about 686 hectares) of land cover in North Carolina (SEGAP 2023 ).
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2025 NC Wildlife Action Plan
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