4.4 Terrestrial Communities
• Ultramafc outcrop barrens occur on dunite, peridotite, or serpentinite. Tese rocks are associated with unusual vegetation and endemic species throughout the world because of their unusual chemistry. North Carolina’s only well-developed ultramafc outcrop barren is tied to specialized soils and is an open savanna-like community with a scat- tered pitch pine canopy and grassy ground cover. • Diabase glades occur in the Piedmont over outcrops of diabase and potentially over other mafc rocks. As with other glade communities, the soil and vegetation are patchy and range from nearly bare rock to patches deep enough to support trees. Te vege- tation includes many species shared with other high pH soil communities and some species found on granitic fatrocks. • High elevation mafc glade communities are an extremely rare community type, with only three examples known globally. A single known location in North Carolina occurs on a fat exposure of amphibolite in Ashe County. Lichens, including a species found nowhere else ( Cladonia psoromica ), dominate much of the area. Herbs on thin soil mats and in crevices include both lowland species and northern disjunct species. Woody species occur in deeper soils and crevices.
Tis natural community description is a new addition to the WAP.
4.4.5.2 Location of Habitat Tis natural community has locations in both the Piedmont and Mountain ecoregions. Piedmont examples are less rare, but a couple of the community types occur only in the Mountains. According to the most recent Southeast GAP analysis, glades and barrens com- prise approximately 11 acres (about 5 hectares) of land cover in North Carolina (SEGAP 2007; NatureServe 2007) . 4.4.5.3 Problems Affecting Habitats Tese communities have been substantially altered by fre suppression, and some of these changes may shift them toward more natural composition. Fire is believed to be a natural part of these communities. Low intensity fres may beneft these communities, but climate change may bring higher potential for wildfres to be severe. Species adapted to mafc glade habitats are tolerant of drought and heat. Higher average temperatures, coupled with drought conditions, will likely increase occurrence of fre. Drought appears to be an important factor in keeping these communities from becoming dense forests. While these are among the driest sites in the Piedmont region, if droughts become much more extreme they may be beyond the tolerance of some of the species.
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2015 NC Wildlife Action Plan
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