LOCATION JEFFERSON          KY+TN VA WV
Established Series
Rev. JMR-HCD
02/2010

JEFFERSON SERIES


The Jefferson series consists of deep and very deep, well-drained soils on mountain sides and foot slopes. They formed in colluvium from soils formed in residuum of acid sandstone, shale, and siltstone. Permeability is moderately rapid. The average annual precipitation is about 49 inches, and the average annual temperature is about 57 degrees F. Slopes range from 2 to 75 percent.

TAXONOMIC CLASS: Fine-loamy, siliceous, semiactive, mesic Typic Hapludults

TYPICAL PEDON: Jefferson gravelly silt loam--on a convex 20 percent slope on the lower part of a steep mountain side in woods. (Colors are for moist soils.)

A--0 to 3 inches; dark grayish brown (10YR 4/2) gravelly silt loam; moderate fine granular structure; friable; many very fine roots; 20 percent pebbles; strongly acid; clear wavy boundary.

E--3 to 9 inches; yellowish brown (10YR 5/4) gravelly silt loam; weak fine granular structure; friable; common fine roots; 20 percent pebbles; strongly acid; clear wavy boundary. (4 to 9 inches thick)

BE--9 to 23 inches; yellowish brown (10YR 5/6) silt loam; weak very fine subangular blocky structure; friable; common medium roots; 10 percent pebbles; very strongly acid; gradual wavy boundary. (0 to 14 inches thick)

Bt--23 to 40 inches; yellowish brown (10YR 5/6) gravelly loam; moderate fine subangular blocky structure; friable; few fine roots; many thin clay films on faces of peds; 25 percent pebbles; 25 percent pebbles; strongly acid; gradual wavy boundary. (10 to 30 inches thick)

BC--40 to 75 inches; yellowish brown (10YR 5/6) very gravelly loam; many medium distinct light yellowish brown (10YR 6/4) mottles; weak medium subangular blocky structure; friable; few clay films on faces of peds; few fine roots; 40 percent pebbles; strongly acid; gradual smooth boundary. (24 to 40 inches thick)

TYPE LOCATION: Harlan County, Kentucky; 150 feet north of U.S. Highway 119, near borrow pit, 3 1/2 miles northeast of Harlan, about 1 mile east of Rosspoint.

RANGE IN CHARACTERISTICS: Thickness of the solum is more than 40 inches. Depth to bedrock ranges from 50 to more than 80 inches. Content of rock fragments of sandstone range from 5 to 35 percent to a depth of about 40 inches, and below 40 inches from 20 to 80 percent. Some areas are stony to extremely stony. The soil ranges from strongly to very strongly acid, excep the A horizons which range from very strongly acid to neutral.

The A horizon has hue of 10YR, value of 3 to 5, and chroma of 1 to 3. The Ap horizon has hue of 10YR, value of 4 or 5, and chroma of 2 to 4. They are silt loam, loam, fine sandy loam, or sandy loam, or gravelly or cobbly analogs.

The E horizon has hue of 10YR, value of 4 to 6, and chroma of 3 or 4. Texture is similar to the A horizon.

The BE horizon has hue of 10YR, value of 4 to 6, and chroma of 4 to 8. They are silt loam, loam, or sandy loam, or the gravelly or cobbly analogues.

Some pedons have BA horizons similar to the BE horizon.

The Bt horizon has hue of 10YR or 7.5YR, value of 4 to 6, and chroma of 4 to 8. Some pedons have mottles in shades of brown, yellow, red, and the lower part shades of gray. It is loam, sandy loam, sandy clay loam, or clay loam, or the gravelly or cobbly analogues.

The BC horizon is in shades of brown, red, or gray, and are usually mottled. It is very gravelly, very channery, extremely gravelly, or extremely channery analogs of sandy loam, fine sandy loam, sandy clay loam, loam, or clay loam.

The C horizon, where present, has color and texture ranges like the BC horizon. Some pedons have a 2C horizon, below a depth of about 50 inches, that are from shaly material with a higher content of clay.

COMPETING SERIES: These are Lily, Lonewood, Marr, Riney, Sassafras, and Sunnyside series. Lily soils have bedrock at less than 40 inches. Lonewood, Marr, and Sassafras soils lack coarse fragments in the solum. Riney and Sunnyside soils have hue redder than 7.5YR in some part of the Bt horizon.

GEOGRAPHIC SETTING: Jefferson soils are on steep mountain sides and foot slopes, often below sandstone escarpments, with slopes ranging from 2 to 75 percent. These soils formed in colluvium from soils formed in residuum of acid sandstone, shale, and siltstone. Near the type location the average annual precipitation is about 49 inches and the average annual temperature is about 57 degrees F.

GEOGRAPHICALLY ASSOCIATED SOILS: These are Clymer, Dekalb, Gilpin, Muse, Ramsey, Shelocta, and Whitley series. Clymer soils have mixed mineralogy. Dekalb and Ramsey soils lack argillic horizons. Gilpin soils have bedrock at depths of less than 40 inches. Muse soils are clayey, and Whitley soils are fine-silty. Shelocta soils have mixed mineralogy.

DRAINAGE AND PERMEABILITY: Well drained with rapid or medium runoff, depending on slope. Permeability is moderately rapid.

USE AND VEGETATION: Most areas are in forest but less steep areas are used mainly for pasture and crops. The forest vegetation is chiefly yellow-poplar, upland oaks, Virginia and shortleaf pine, hickory, and laurel.

DISTRIBUTION AND EXTENT: Eastern Kentucky, Tennessee, West Virginia, Georgia, and Virginia. The series is extensive.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Morgantown, West Virginia

SERIES ESTABLISHED: Reconnaissance Survey of Southwestern Pennslyvania; 1909.

REMARKS: Jefferson series formerly included Paleudults. Lab data of representative pedon reveal silt loam texture in the A and E horizons.

Diagnostic horizons and features recognized in this pedon are:

Ochric epipedon: 0 to 9 inches (A,E)

Argillic horizon: 9 to 40 inches (BE, Bt)

ADDITIONAL DATA: Characterization sample S84KY-095-001


National Cooperative Soil Survey
U.S.A.