LOCATION CUNNINGHAM GAEstablished Series
The Cunningham series consists of well drained, deep, slowly permeable soils on uplands. These soils have brown loam A horizons, yellowish red clay and clay loam Bt horizons and C horizons of weathered shale. Slopes range from 2 to 25 percent. Near the type location mean annual temperature is 61 degrees F, and mean annual precipitation is 53 inches.
TAXONOMIC CLASS: Fine, mixed, semiactive, thermic Typic Hapludults
TYPICAL PEDON: Cunningham loam--soybeans. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 5 inches; brown (7.5YR 5/4) loam; weak fine granular structure; friable; common fine roots; few fine worm holes; very strongly acid; abrupt smooth boundary. (4 to 9 inches thick)
Bt1--5 to 17 inches; yellowish red (5YR 5/8) clay; moderate medium angular blocky structure; firm; few fine roots and worm holes; common prominent clay films on faces of peds; very strongly acid; clear wavy boundary.
Bt2--17 to 30 inches; yellowish red (5YR 4/6) clay loam; many medium distinct dark red (2.5YR 3/6) and strong brown (7.5YR 5/6) mottles; moderate medium subangular and angular blocky structure; firm; few fine roots and worm holes; common prominent clay films on faces of peds; few shale fragments; very strongly acid; clear wavy boundary. (Combined thickness of the Bt is 18 to 37 inches.)
BC--30 to 36 inches; mottled yellowish red (5YR 4/6), dark red (2.5YR 3/6) and strong brown (7.5YR 5/6) clay loam; weak medium subangular blocky structure; firm; common shale fragments and gravel; extremely acid; abrupt irregular boundary. (0 to 18 inches thick)
C--36 to 46 inches; olive brown (2.5Y 4/4) weathered shale; crushes to a loam texture; very strongly acid; abrupt irregular boundary. (4 to 10 inches thick)
Cr--46 to 60 inches; olive brown (2.5Y 4/4) consolidated shale bedrock.
TYPE LOCATION: Floyd County, Georgia; 3.3 miles west of U.S. Highway 27 on Georgia Highway 53 and U.S. Highway 411, 0.5 mile west of Georgia Highway 53 on Cunningham Road, 25 yards south of road.
RANGE IN CHARACTERISTICS: Solum thickness and depth to weathered shale ranges from 30 to 56 inches. Depth to consolidated shale bedrock ranges from 40 to 60 inches. Reaction of all horizons ranges from strongly acid to extremely acid, except where limed. Base saturation is more than 35 percent in the upper Bt horizon. The content of shale fragments range from 0 to 12 percent in the A and upper Bt horizons, from 10 to 25 percent in the lower Bt horizon, and the BC horizons range up to 50 percent. The weighted average clay content of the upper 20 inches of the Bt horizon ranges from 40 to 65 percent.
The A horizon has hue of 10YR, 7.5YR or 5YR; value of 4 or 5; and chroma of 2, 3, 4, 6 or 8. It is silt loam or loam, fine sandy loam, sandy loam and where eroded, silty clay loam, sandy clay loam or silty clay.
The Bt1 horizon has hue of 7.5YR, 5YR or 2.5YR; value of 4, 5 or 6; and chroma of 6 or 8. It is sandy clay loam, silty clay loam, silty clay, clay loam or clay. The Bt2 horizon has the same colors as above horizon and mottles are none to common in shades of olive, yellow, brown and red. The BC horizon is mottled red, brown, yellow and olive. Texture of the Bt2 and BC horizons is clay, silty clay, clay loam or silty clay loam with channery analogs.
The C horizon is mottled with hue of 5YR to 2.5Y, value of 3 to 6, and chroma of 3 to 6. The Cr horizon is consolidated shale bedrock with colors same as horizon above. Some pedons have interbedded shale and sandstone.
COMPETING SERIES: These are the Albertville, Badin, Brockroad, Carnasaw, Catharpin, Coghill, Corryton, Cuthbert, Kirvin, Luverne, Marbledale (T), Masada, Mayodan, McQueen, Nason, Peakin (T), Sweatman, Tatum, Townley, Uwharrie, and Vance series. Albertville, Carnasaw, Kirvin, and McQueen soils have sola more than 40 inches thick. Badin and Townley soils have Cr horizons within 40 inches of the surface. Catharpin soils have a lithological continuity. Bonwier and Urland soils formed from Coastal Plain sediments of Pleistocene Age. Coghill, Corryton, Luverne, and Marbledale (T) soils are very deep. Cuthbert soils have base saturation less than 35 percent in the upper Bt horizon. Masada, Nason, Tatum, Uwharrie, and Vance soils formed in materials weathered from crystalline rocks of the Piedmont. Mayodan and Peakin (T) soils formed in materials weathered from Triassic rocks. Additionally, Peakin soils have a perched water table 3 to 6 feet deep. Sweatman soils have mica flakes in the profile.
GEOGRAPHIC SETTING: Cunningham soils are very gently sloping to steep with dominant slopes of 2 to 15 percent, but ranging to 25 percent. The soil formed in materials weathered from acid shales containing thin strata of limestone, siltstone or sandstone in some areas. The average annual temperature is 60 to 65 degrees F, and the average annual precipitation is 45 to 55 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Albertville and Townley series, and the Allen, Conasauga, Holston, and Montevallo series. Allen and Holston soils have sola more than 60 inches thick. Conasauga soils have base saturation of more than 35 percent in the lower Bt horizon. Montevallo soils lack argillic horizons.
DRAINAGE AND PERMEABILITY: Well drained; rapid runoff; slow permeability.
USE AND VEGETATION: Principal use is woodland, consisting of mixed hardwood and pine. Some areas are cropped to corn, cotton, or soybeans; others are used for pasture or hay.
DISTRIBUTION AND EXTENT: The Southern Appalachian Ridges and Valleys of Georgia, Alabama, and Tennessee. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Morgantown, West Virginia
SERIES ESTABLISHED: Floyd County, Georgia, 1975; Chattooga, Floyd, and Polk Counties, Georgia survey area.
REMARKS: The 8/01 revision assigns a semiactive CEC activity class to the series.
Diagnostic horizons recognized in this pedon are:
Ochric horizon - the zone from the soil surface to a depth of 5 inches (Ap horizon).
Argillic horizon - the zone from 5 to 36 inches (Bt1, Bt2, and BC horizons).