Common (Translated Scientific) Name: Rock Spikemoss - Little Bluestem - Orange-grass - Dense-tuft Hairsedge Rocky Grassland

Colloquial Name: Appalachian Low-Elevation Granitic Dome

Hierarchy Level:  Association

Type Concept: This association includes vegetation found on granitic exfoliation domes of the Piedmont and lower elevation portions of the Blue Ridge. It occurs on gently sloping to steep exposures of smooth, exfoliating granite or similar massive igneous or metamorphic rock, such as granitic gneiss. The substrate has few cracks or irregularities for soil accumulation, and most of the areal extent is bare rock. This association typically occurs at elevations below 915 m (3000 feet) but may be found at slightly higher elevations. This community occurs in large patches, ranging in size from a few acres to over 100 acres. Vegetation consists primarily of lichens on bare rock or of shallow mats generally dominated by Selaginella rupestris occurring with other distinctive species. Woody species from adjacent woodlands and shrublands may be scattered components, rooted in deeper soil pockets, older stable vegetation mats, and in marginal zones between the exposed rock and adjacent forests. Selaginella rupestris is almost always a major dominant of the vegetation mats. However, distribution of Selaginella rupestris can be spotty, so there are examples of this association that do not contain this species. Other characteristic herbaceous species are Baptisia tinctoria, Cheilanthes lanosa, Coreopsis major, Corydalis sempervirens, Danthonia sericea, Lindernia monticola, Phlox nivalis, Schizachyrium scoparium, Scleria triglomerata, and Phemeranthus teretifolius. Common woody species include Carya pallida, Chionanthus virginicus, Fraxinus americana, Juniperus virginiana, Kalmia latifolia, Pinus echinata, Pinus rigida, Quercus montana, Rhododendron minus, Ulmus alata, and Vaccinium stamineum.

Diagnostic Characteristics: No Data Available

Rationale for Nominal Species or Physiognomic Features: No Data Available

Classification Comments: Occurrences of this community have structural and compositional similarities to ~Selaginella tortipila - Krigia montana - Houstonia longifolia Rocky Grassland (CEGL004283)$$, which is typically at higher elevations (over 915 m [3000 feet]) and contains a suite of species not found at lower elevations. Occurrences vary locally based on slope steepness, aspect, age of vegetation mats, and smoothness of rock substrate. Some occurrences may be difficult to distinguish from ~Selaginella rupestris - Schizachyrium scoparium - Hylotelephium telephioides - Allium cernuum Granitic Glade Vegetation (CEGL004991)$$, which is characterized by the presence of plants characteristic of higher pH conditions, better developed soils, and flat to gently sloping rock surfaces. This community is floristically similar to granitic flatrock communities which are scattered throughout the Piedmont from Virginia to Alabama. However, the steep domes described here lack the shallow pools and other microhabitats characteristic of the fractured rock in granitic flatrock communities, and thus have different vegetative components.

In an 1134-plot regional analysis (Georgia, North Carolina, Tennessee, Virginia) for the Southern Appalachian portion of the Appalachian Trail, two plots from Union County, GA, were classified as this association. Both plots are at an unusually high elevation for the type and may be transitional to a higher-elevation association, but contain the characteristic species Selaginella rupestris, Schizachyrium scoparium, and Bulbostylis capillaris, along with Danthonia spicata, Deschampsia flexuosa, Hypericum prolificum, and Croton michauxii var. ellipticus (Fleming and Patterson 2009a).

Similar NVC Types: No Data Available

note: No Data Available