Cumberland Plateau Sandstone Outcrop
Cumberland Sandstone Glade & Barrens Ecological System (NatureServe 2015)
Sandstone Outcrops (Schmalzer 1985)
Northeastern Middle-Tennessee (Fentress, eastern Pickett, and northwestern Scott counties) where restricted to tops of cliffs along river gorges.
Shrubs, grasses and forbs, with few trees dominate this small patch community that ranges in height from 0.05 – 3.00 m. It occurs as islands of vegetation whose physiognomy is closely associated with the depth of soil pockets present, with herbs and grasses growing in the shallowest patches and interstices, shrubs, herbs, and grasses growing in yet deeper soils, and trees growing in the deepest, but still relatively shallow, soils (Perkins 1981). Data are lacking to demonstrate effects of groundwater seepage on vegetation of this community.
This community occurs in the Cumberland Plateau level IV ecoregion on base slopes of escarpments, side slopes of interfluves, hillslopes, and ridges, free faces of hillslopes and gorges, and shoulders of gorges from 396-502 m (1300-1650 ft). It occurs generally on rock outcrops with a southerly aspect, but also on east-, southeast-, southwest- and west-facing outcrops from 5 to 70 percent slopes. Perkins (1981) mentions slight community variation on north-facing outcrops due to increased moisture, but this was for a site outside the range of this community. More research may reveal that this community occurs on any aspect. The underlying geology is composed of Pennsylvanian-aged conglomeritic sandstone of the Rockcastle formation transitioning into Pennsylvanian-aged shales, siltstones, and sandstones of the Fentress formation. Much of this bedrock is exposed with islands of shallow soils of various depths. These loams, cobbly-loams, and fine-sandy loams are well-drained to somewhat excessively drained ultisols and inceptisols ranging in pH from 4.6-5.0.
Soil series involved:
- GeF- Grimsley-Jefferson-Rock outcrop complex, 20 to 60 percent slopes; Escarpments- base slope; well-drained; loamy-skeletal, siliceous, mesic Typic Hapludults; pH=5.0; surface texture=cobbly loam
- Jefferson-Ramsey complex, 15-35 percent slopes; Interfluves- side slope; well-drained to somewhat excessively-drained; Fine-loamy, siliceous, mesic Typic Hapludults; pH=5.0; surface texture=loam
- Ramsey-Alticrest-Rock outcrop complex 5 to 20 percent slopes; Hillslopes- sideslope and free face; well-drained to somewhat excessively-drained; Loamy, siliceous, mesic Lithic Dystrochrepts; pH=5.0; surface texture=loam
- Rock outcrop-Ramsey complex, 20 to 70 percent slopes; Gorges- Free face and shoulder; somewhat excessively drained;
- Lily-Ramsey complex 20 to 35 percent slopes; Ridges- sideslopes; well-drained to somewhat excessively drained; Fine-loamy, siliceous, semiactive, mesic Typic Hapludults; pH=4.6; surface texture= fine sandy loam
- Lily-Ramsey complex 12 to 20 percent slopes; Ridges- sideslopes; well-drained to somewhat excessively drained; Fine-loamy, siliceous, semiactive, mesic Typic Hapludults; pH=4.6; surface texture= fine sandy loam
- Lily loam, 5 to 12 percent slopes; Ridges- sideslopes; well-drained; Fine-loamy, siliceous, semiactive, mesic Typic Hapludults; pH=4.6; surface texture=loam
Like other Southern Appalachian rock outcrops, shallow, poor soils, wind, high sunlight, and potentially fire are the main natural processes that affect maintenance of these communities.
Trees: Pinus virginiana (Virginia pine); Subcanopy: Amelanchier arborea (serviceberry); Shrubs: *Aronia arbutifolia (red chokeberry), Aronia melanocarpa (black chokeberry), *Gaylussacia baccata (black huckleberry), *Gaylussacia brachycera (box huckleberry), Kalmia latifolia (mountain laurel), Vaccinium arboreum (farkleberry), and *Vaccinium pallidum (lowbush blueberry). Subshrubs: Gaultheria procumbens (wintergreen); Lianas: *Smilax glauca (cat greenbrier) and Herbaceous Layer: *Andropogon virginicus (broom sedge), *Danthonia compressa (flattened oat grass), *Danthonia sericea (downy danthonia), *Dichanthelium acuminatum ssp. acuminatum (tapered rosette grass), Eurybia surculosa (creeping aster), Liatris microcephala (small-head blazing star), *Schizachyrium scoparium (little bluestem) (Perkins 1981; Schmalzer 1985).
Phemeranthus teretifolius (roundleaf fameflower)
Community Variation and Subtypes
Lithophyte zone, Cryptogam-herb zone, shrub-herb zone, tree zone (Perkins 1981)
Associated Natural Communities
Cumberland Plateau Montane Pine Forest, Cumberland Plateau Xeric Acidic Forest, Cumberland Plateau Sandstone Cliff
Cumberland Plateau Sandstone Glade, Cumberland Plateau Riverscour Glade & Outcrop
Presettlement Distribution and Size
The current distribution of this community is the same as presettlement times. The cumulative size of all examples of the community is difficult to estimate because the role of fire in slowing succession of rock outcrops is unknown.
The development of houses on cliff lines, trampling by hikers, and ATV trails in the northern Cumberland Plateau backcountry degrade this community, but many sites are protected by Pickett State Park and Big South Fork National River and Recreation Area, placing the community at vulnerable status.
Scott Co.: John Muir loop trail, Big South Fork NRRA (36.519354, -84.659059)
Pickett Co.: Lookout at Pogue Creek Gorge (36.542072, -84.863630)
Fire suppression, logging, invasive species, ATV traffic, coal mining, trails (and hikers), and development adjacent to cliffs. The combination of these threats with poor understanding of the community, like many communities in the state of Tennessee, is the greatest threat to this community because we can’t protect what we don’t know about.
Though baseline floristic, vegetation, and ecology research is lacking for this community, management for the health of the community should probably consider prescribed fire, removal of invasive species (if present), limiting access by ATVs and hikers, restoration of natural hydrology.
Future Research Needs
Baseline data on sandstone outcrop vegetation and flora of the Cumberland Plateau need to be collected. Fire ecology of sandstone outcrops is unknown and much needed.
Perkins (1981) conducted an ecological study of various sandstone rock outcrop communities of the Cumberland Plateau Physiographic Province. This study compared plant communities at individual sites and across sites from AL, GA, and TN, with references to Kentucky, Ohio, and Indiana.
Allawos J.G. 1994. The vascular flora of North White Oak Creek Gorge, Scott and Fentress Counties, Tennessee. M.S. Thesis, University of Tennessee, Knoxville
Comer, P., D. Faber-Langendoen, R. Evans, S. Gawler, C. Josse, G. Kittel, S. Menard, M. Pyne, M. Reid, K. Schulz, K. Snow, and J. Teague. 2003. Ecological systems of the United States: A working classification of U.S. terrestrial systems. NatureServe, Arlington, VA.
DeSelm, H. R., and N. Murdock. 1993. Grass-dominated communities. Pages 87-141 in: W. H. Martin, S. G. Boyce, and A. C. Echternacht, editors. Biodiversity of the southeastern United States: Upland terrestrial communities. John Wiley and Sons, New York.
Evans, M. 1991. Kentucky ecological communities. Draft report to the Kentucky Nature Preserves Commission. 19 pp
Geology available at Tennesse Spatial Data Server which can be found at http://www.tngis.org/geology.html which links to a USGS Water Resources Division site: http://water.usgs.gov/lookup/getspatial?geo250k Tennessee Spatial Data Server site notes: Thanks goes to Jim Julian for researching this improved geology layer from the Tennessee Division of Geology. **Note** - The Tennessee Division of Geology does not endorse this coverage, stating this version is still incomplete and not fit for distribution.Noss, R. F. 2013. Forgotten grasslands of the South: Natural history and conservation. Island Press, Washington, DC. 317 pp.
NatureServe. 2014. NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia. Available http://explorer.natureserve.org. (Accessed: March 1, 2015).
Perkins, B. E. 1981. Vegetation of sandstone outcrops of the Cumberland Plateau. M.S. thesis, University of Tennessee, Knoxville. xi plus 121 pp.
Quarterman, E., M. P. Burbanck, and D. J. Shure. 1993. Rock outcrop communities: Limestone, sandstone, and granite. Pages 35-86 in: W. H. Martin, S. G. Boyce, and A. C. Echternacht, editors. Biodiversity of the southeastern United States: Upland terrestrial communities. John Wiley and Sons, New York.
Schmalzer PA, Patrick TS, DeSelm HR. 1985. The vascular flora of the obed wild and scenic river, Tennessee. Castanea 50(2): 71-88.
Soil Survey Staff, Natural Resources Conservation Service, United States Department of Agriculture. Web Soil Survey. Available online at http://websoilsurvey.nrcs.usda.gov/. Accessed [02/25/2015].