4.4 Terrestrial Communities
• Grassy balds are open meadows typically dominated by mountain oatgrass and sedges, with a fairly diverse mixture of other species. Tey usually occur on broad ridgetops. • Heath balds are dense thickets of tall shrubs. Catawba Rhododendron and Mountain Laurel are the most common dominants. An unusual dominant at Roan Mountain is Green Alder, not found elsewhere in North Carolina. Most heath balds are on sharp spur ridges, but some occur on rounded peaks or ridgetops. High-elevation communities are characterized by cool temperatures, relatively high moisture levels within forests, short growing seasons, exposed rock and acidic soils, and extreme weather events. Canopy trees are often misshapen due to persistent strong winds. Open (sparse-to-no tree canopy) communities such as heath or grassy balds and rock outcrops are scattered throughout. Spreading Avens (a federally listed endangered plant species) is endemic to high-elevation grassy balds (Wear and Greis 2012) . It has been discovered that some places that superfcially resemble balds were cleared of forest in historical times, but other balds apparently were open throughout history. Te presence of disjunct species which require open habitat suggests that some balds have been open since the Ice Age. Large herbivores, such as Elk and Bison may have kept grassy balds open through grazing. Another possibility is that Native Americans worked to keep grassy balds open for game by burning or by other clearing methods.
Tis natural community description is a new addition to the Wildlife Action Plan.
4.4.6.2 Location of Habitat Grass and heath balds occur only in the highest mountain ranges of western North Carolina, notably in the Great Smokies, Plott Balsams, Great Balsams, Black/Craggy Mountains, Grandfather Mountain, Roan Mountain, and in the Amphibolite Mountains of Ashe County ( NCWRC 2005 ).According to the most recent Southeast GAP analysis, grass and heath balds comprise approximately 4,761 acres (about 1,927 hectares) of land cover in North Carolina (SEGAP 2007; NatureServe 2007) . Tis represents only 0.2% of land cover in the state. 4.4.6.3 Problems Affecting Habitats Warmer temperatures, changes in precipitation or fre regime, or climate-change induced competition from ofsite plants may threaten grassy balds (Wear and Greis 2012) . Grassy balds and some of the heath balds are already seriously threatened by invasionfrom native trees and shrubs. Te current invasion of native trees and shrubs, development, and conversion
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2015 NC Wildlife Action Plan
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