130B—Southern Blue Ridge

This MLRA (shown in red in the figure above) is in North Carolina (51 percent), Tennessee (18 percent), Georgia (17 percent), Virginia (10 percent), and South Carolina (4 percent). It makes up about 16,080 square miles (41,665 square kilometers). It is locally known as the Southern Appalachians. It includes Lenoir, Morganton, Marion, Hendersonville, Waynesville, and Asheville, North Carolina; Gatlinburg, Tennessee; Damascus and Galax, Virginia; Walhalla, South Carolina; and Cleveland, Dahlonega, and Ellijay, Georgia. Interstate 40 crosses the parts of the area in Tennessee and North Carolina. Interstate 77 crosses the part in Virginia. Many national forests are in the area, including the Jefferson, Cherokee, Nantahala, Pisgah, and Chattahoochee National Forests. The Appalachian Trail begins on Springer Mountain in Georgia, near Amicalola State Park. The Great Smoky Mountains National Park is in this MLRA. The Mount Rogers National Recreation Area is in the part of the MLRA in Virginia. The Cherokee Indian Reservation is west of Waynesville, North Carolina.

Physiography

This MLRA is mainly in the Southern Section of the Blue Ridge Province of the Appalachian Highlands. The southern tip of the MLRA and two protruding areas to the east are in the Piedmont Uplands Section of the Piedmont Province of the Appalachian Highlands. This MLRA consists of several distinct topographic areas, including the Blue Ridge Escarpment on the eastern edge of the area, the New River Plateau on the northern end, interior low and intermediate mountains throughout the MLRA, intermountain basins between the major mountains, and the high mountains making up the bulk of the MLRA. Elevation ranges from about 900 feet (275 meters) at the south and southwest boundaries of the area to more than 6,600 feet (2,010 meters) at the crest of the Great Smoky and Black Mountain ranges.

The extent of the major Hydrologic Unit Areas (identified by four-digit numbers) that make up this MLRA is as follows: Upper Tennessee (0601), 46 percent; Kanawha (0505), 13 percent; Middle Tennessee-Hiwassee (0602), 12 percent; Edisto-Santee (0305), 9 percent; Alabama (0315), 8 percent; Ogeechee-Savannah (0306), 6 percent; Pee Dee (0304), 4 percent; Chowan-Roanoke (0301), 1 percent; and Apalachicola (0313), 1 percent. From north to south, the major rivers in this area are the New River in Virginia; the Yadkin, Catawba, French Broad, Little Tennessee, and Hiwassee Rivers in North Carolina; the Saluda, Seneca, Chattooga, and Tugaloo Rivers in South Carolina; and the Toccoa and Coosawattee Rivers in Georgia. The Tugaloo River is a headwater stream of the Savannah River, and the French Broad, Little Tennessee, Hiwassee, and Ocoee Rivers also flow into Tennessee in this area. The Hiwassee River in Tennessee and the Conasauga River in Georgia have been designated National Wild and Scenic Rivers in this area. The Chattooga River in South Carolina is a National Scenic River.

Geology

The bedrock geology in this area consists mostly of Precambrian metamorphic rock formations with a few small bodies and windows of igneous and sedimentary rocks. The degree of metamorphism varies but generally decreases westward. The higher grade metamorphic rocks include formations of gneiss, schist, and amphibolite. Low-grade metamorphic formations in the southwestern part of the MLRA include distinct and interbedded bodies of metasandstone, slate, phyllite, metasiltstone, and metaconglomerate. Surficial deposits include colluvial material on fans and aprons along the ridges and alluvial material along the major streams.

Climate

The average annual precipitation in this area generally is 36 to 60 inches (915 to 1,525 millimeters), generally increasing with elevation. It is 60 to 90 inches (1,525 to 2,285 millimeters) in southwestern North Carolina and northeastern Georgia and can be as much as 119 inches (3,025 millimeters) on the higher peaks in the MLRA. Much of the precipitation occurs as snow at the higher elevations. The amount of precipitation is lowest in the fall. The average annual temperature ranges from 46 to 60 degrees F (8 to 16 degrees C), decreasing with elevation. The freeze-free period averages 185 days and ranges from 135 to 235 days. The freeze-free period is shorter at high elevations and on valley floors because of cold air drainage. Microclimate differences resulting from aspect significantly affect the type and vigor of the plant communities in the area. South- and west-facing slopes are warmer and drier than north- and east-facing slopes and those shaded by the higher mountains.

Water

Following are the estimated withdrawals of freshwater by use in this MLRA:

Public supply—surface water, 4.6%; ground water, 1.8%
Livestock—surface water, 4.4%; ground water, 1.0%
Irrigation—surface water, 0.2%; ground water, 0.1%
Other—surface water, 85.3%; ground water, 2.7%

The total withdrawals average 710 million gallons per day (2,685 million liters per day). About 6 percent is from ground water sources, and 94 percent is from surface water sources. Streams, some ponds, and springs provide water for livestock. Springs also supply some domestic drinking water. The many rivers crossing this area are sources of public supply and industrial water. The Tennessee Valley Authority, Duke Power, and Alcoa operate several reservoirs and dams for electric power production, flood control, water supply, and recreation. Protected watersheds and reservoirs supply water to municipal areas. These watersheds commonly are protected lands managed by the U.S. Forest Service and are sources of high-quality water. Most of the water is of excellent quality and is suitable for most uses. Acid-mine drainage from coal mines in the Appalachian Plateau to the west of the northern end of this area causes some contamination in rivers draining that area. The limestone bedrock underlying these drainages, however, provides enough carbonates in runoff water to mitigate most of the contamination, so this surface water is still usable within this area. Wastewater discharges from textile, wood, and paper mills in North Carolina can cause some local water-quality problems.

Springs and shallow wells provide domestic water in rural areas, but the yields of ground water from wells are generally small and variable. The water is in joints and fractures within the rocks, so deep wells are required to intercept enough openings to obtain a suitable yield. The abundance of ground water depends largely on landscape position and geology. The most abundant sources generally are in coves and valleys. The sources on side slopes and ridge summits are not so abundant or dependable. The primary source of domestic ground water in this area is the Piedmont and Blue Ridge crystalline rock aquifer in Virginia and South Carolina or the Crystalline Rock aquifer in the other States in the area. It consists of intrusive igneous and metamorphic rocks. This water has very low levels of total dissolved solids and is generally soft or moderately hard. In Virginia, it generally is acidic, and the acidity can damage copper and lead in pipes and plumbing connections. The iron content and hardness vary with the mineralogy of the source rocks. Iron levels are generally less than 300 parts per billion (micrograms per liter), which is the national secondary standard (for esthetics) for drinking water. The median level of iron in the ground water in Tennessee is twice the level in the ground water in the other States in the area. Naturally high radiation levels are common in the ground water in Virginia.

Soils

The dominant soil orders in this MLRA are Inceptisols and Ultisols. The soil moisture regime is udic. The soil temperature regime typically is mesic, but it is frigid at elevations above 4,200 feet (1,280 meters). Soil depth ranges from shallow to very deep. The general textural class is loamy or clayey.

In areas at elevations of less than 3,500 feet (1,065 meters), the soils on uplands generally are red, fine-loamy or fine Typic Hapludults (Evard, Junaluska, and Hayesville series). Humic Hapludults (Trimont and Snowbird series) are on north and east aspects. Soils that formed in colluvium in coves are Typic Dystrudepts (Tate, Greenlee, and Northcove series), Typic Hapludults (Lonon and Keener series), or Humic Hapludults (Saunook and Thunder series).

At elevations between 3,500 and 4,200 feet (1,065 and 1,280 meters), the soils on uplands generally are brown, fine-loamy or coarse-loamy Dystrudepts. Humic Dystrudepts (Plott, Porters, and Cheoah series) are common on north and east aspects, and Typic Dystrudepts (Edneyville, Chestnut, Ditney, and Stecoah series) are common on south and west aspects. Soils that formed in colluvium in coves are Humic Dystrudepts (Cullasaja, Spivey, Tuckasegee, and Santeetlah series) or Humic Hapludults (Saunook and Thunder series).

In areas at elevations above 4,200 feet (1,280 meters), the soils on uplands generally are brown, fine-loamy or coarse-loamy Humic Dystrudepts with a frigid soil temperature regime (Burton, Oconaluftee, and Breakneck series). Soils that formed in colluvium also are Humic Dystrudepts (Balsam and Chiltoskie series). Soils that formed in alluvium vary with stream gradient, energy, and entrenchment into the valley floor. In the upper reaches of watersheds where flood plains are narrow, the soils are Oxyaquic and Fluvaquentic Dystrudepts (Dellwood, Reddies, and Cullowhee series). In the lower and broader river valleys, Udipsamments (Biltmore series) and coarse-loamy Dystrudepts (Rosman series) are in areas closest to rivers and streams on flood plains. Humaquepts (Ela, Nikwasi, and Toxaway series) are in low-lying, frequently flooded or ponded areas. Ultisols are most common on the more stable stream terraces. Fine-loamy Aquic and Typic Hapludults (Dillard and Statler series) are on low terraces, and fine Typic Hapludults (Braddock and Unison series) are on high terraces.

Biological Resources

This area supports a wide diversity of plant and animal life because of highly varied topography and climatic conditions. The kind of vegetation changes with elevation and slope aspect. At the lower elevations, below 3,000 feet (915 meters), the most common trees are white oak, black oak, scarlet oak, chestnut oak, hickory, eastern white pine, Virginia pine, and pitch pine. Yellow-poplar and northern red oak are common in the northern part of the MLRA. At the middle elevations, the most common trees are yellow-poplar, black cherry, black birch, sugar maple, northern red oak, American basswood, eastern hemlock, and yellow buckeye. At the higher elevations, above 5,000 feet (1,525 meters), red spruce and Fraser fir are the dominant tree species. In some areas at a high elevation, grassy and heath “balds” are evident. These are large meadows or treeless areas. Grassy balds are dominated by grass species and are home to rare shade-intolerant plant varieties. Heath balds support shrubs, such as rhododendron, mountain laurel, blueberry, flame azalea, hawthorn, huckleberry, and sand myrtle.

The diverse plant communities provide habitat for many species of wildlife. Black bear, white-tailed deer, and wild turkey are plentiful. The higher elevations provide suitable habitat for the birds and animals that are common in northern latitudes, such as northern saw-whet owl, Canada warbler, common raven, northern flying squirrel, and red squirrel.

Land Use

Following are the various kinds of land use in this MLRA:

Cropland—private, 4%
Grassland—private, 10%; Federal, 3%
Forest—private, 46%; Federal, 23%
Urban development—private, 8%; Federal, 1%
Water—private, 2%; Federal, 1%
Other—private, 1%; Federal, 1%

More than two-thirds of this area is forestland used for timber production, watershed protection, recreation, and wildlife habitat. The federally owned forestland in the area is mainly U.S. Forest Service or National Park Service land. The small acreage of cropland is used for vegetables, fruit orchards, native ornamental crops, and Christmas trees as well as corn and small grain. About 10 percent of the MLRA is in pastured areas used for dairy, beef, and wool production. The largest urban area in this MLRA is Asheville, North Carolina. The MLRA is a popular area for tourism and retirement living. As a result, steady or rapid urban growth occurs in many areas.

Erosion from poorly constructed and maintained access roads is a major management concern in this area. Sediment from access roads and urban development is the main pollutant of streams in the area.

Poor air quality, especially in summer, is both a health and economic problem. Air pollution flowing from the industrial Midwest affects people who are sensitive to pollutants, such as ozone, and those who suffer from breathing disorders. At high elevations, air pollution and acid deposition are thought to be partially responsible for damage to the spruce and fir forests.

Proper woodland management is extremely important since privately held forestland makes up a significant portion of the land area in this MLRA. Proper design and construction of access roads and stabilization of roadbanks can minimize the impact of timber management on water quality.

Conservation practices in agricultural areas include field borders, grassed waterways, diversions, and riparian buffers along streams. Prescribed grazing and proper forage, nutrient, and pest management practices are critical in maintaining the productivity of grazing land.

In areas where streams have been channelized, riparian areas have been removed, and livestock access is unchecked, streambank erosion is a major concern. Stabilizing streambanks and channels and restoring and maintaining riparian forest buffers can maintain or improve water quality. The condition of streambanks and channels becomes increasingly important in managing the storm-water runoff from growing urban areas.

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