LOCATION HOLSTON TN+AL AR GA KY MDEstablished Series
TAXONOMIC CLASS: Fine-loamy, siliceous, semiactive, thermic Typic Paleudults
TYPICAL PEDON: Holston loam - cultivated. (Colors ae for moist soil unless otherwise stated.)
Ap--0 to 8 inches; brown (10YR 5/3) loam; weak medium granular structure; very friable; many roots; strongly acid; clear smooth boundary. (5 to 10 inches thick)
BE--8 to 14 inches; yellowish brown (10YR 5/4) loam; weak medium subangular blocky structure; friable; common roots; 5 percent by volume rounded and angular sandstone fragments up to 1 inch in diameter; very strongly acid; gradual smooth boundary (0 to 10 inches thick)
Bt1--14 to 32 inches; yellowish brown (10YR 5/6) clay loam; moderate medium and fine subangular blocky structure; friable; common roots; few faint clay films; 5 percent by volume rounded and angular fragments of sandstone up to 2 inches in diameter; very strongly acid; gradual smooth boundary.
Bt2--32 to 44 inches; yellowish brown (10YR 5/6) clay loam; moderate medium and fine subangular blocky structure; friable; few roots; common distinct clay films; 10 percent by volume rounded and angular fragments of sandstone up to 2 inches in diameter; very strongly acid; gradual wavy boundary.
Bt3--44 to 62 inches; yellowish brown (10YR 5/6) clay loam; common fine and medium faint pale brown (10YR 6/3) and few fine and medium distinct yellowish red (5YR 5/6) mottles; moderate medium subangular blocky structure; friable; few roots; common distinct clay films; 10 percent by volume fragments of sandstone up to 3 inches in diameter; few small black concretions; very strongly acid; gradual wavy boundary.
Bt4--62 to 75 inches +; strong brown (7.5YR 5/6) clay loam; common fine to coarse distinct pale brown (10YR 6/3), yellowish red (5YR 5/6) and few medium distinct yellow (2.5Y 7/4) mottles; weak medium subangular blocky structure; few distinct clay films; 10 percent by volume fragments of sandstone and chert up to 3 inches across, a few up to 5 inches across; few small black concretions; very strongly acid. (Combined thickness of the Bt horizons is more than 50 inches thick)
TYPE LOCATION: Coffee County, Tennessee; 6 miles east of Manchester; 0.6 mile south of Ragsdale School and 100 feet west of gravel road.
RANGE IN CHARACTERISTICS: Thickness of the solum is more than 60 inches. Depth to bedrock is greater than 5 feet. The soil is strongly acid or very strongly acid except for the surface layer where limed. Fragments of sandstone or chert ranges from 0 to 15 percent to a depth of about 40 inches and 0 to 40 percent below. Some pedons have a stone line at the base of the alluvial deposit.
The Ap horizon has hue of 10YR or 2.5Y, value of 4 or 5 and chroma of 2 to 4 or value of 3 and chroma of 4.. Some pedons have a thin A horizon with hue of 10YR, value of 3 or 4 and chroma of 2 or 3. Texture is loam, fine sandy loam, or sandy loam.
The E horizon has a hue of 10YR or 2.5Y, value of 5 or 6, and chroma of 2 to 4. It is loam, fine sandy loam, or sandy loam.
Some pedons have a transitional horizon between the A or E horizon and Bt horizons.
The Bt horizon has hue of 7.5YR to 2.5Y, value of 4 to 6 and chroma of 4 to 8. It is dominantly loam or clay loam and is rarely sandy clay loam or silty clay loam. Below about 40 inches the Bt horizon also has hue of 5YR and texture of clay. Mottles are in shades of brown, yellow and red and the lower part may have a few gray mottles.
COMPETING SERIES: These are the Addielou, Allen, Avilla, Boma, Etowah, Leesburg, Minvale, Nella, Noboco, Octavia, Orangeburg, Pikeville, Ruston and Warnock soils in the same family and Claiborne, Nolichucky, Norfolk and Smithdale soils in closely related families. Addielou soils have an E horizon greater than 16 inches thick. Allen, Avilla, Boma, Nella, Orangeburg, Pikeville, Ruston and Smithdale soils have hue of 5YR or redder in the major part of the B horizon. Etowah soils have an Ap horizon with value of 3. Leesburg and Minvale soils have more than 15 percent rock fragments in the upper part of the B horizon. Noboco soils have low chroma mottles in the lower Bt horizons. Norfolk is a very close competitor that formed in Coastal Plain sediments and typically has a higher sand content throughout. Octavia soils have a clayey 2Bt horizon. Claiborne and Nolichucky soils have hue of 5YR or redder and are mesic. Warnock soils have brittle lower Btx horizons containing plinthite.
GEOGRAPHIC SETTING: Holston soils are on nearly level to moderately steep stream terraces that are commonly rather high above the floodplains, and on foot slopes and benches in the uplands. Slopes range from 0 to 25 percent. The soil formed in several feet of loamy alluvium or colluvium. At the type location, mean annual air temperature is about 59 degrees F. and mean annual precipitation is approximately 50 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Allen and Leesburg series and the Waynesboro soils on adjacent high terraces, and Sequatchie and Whitwell soils on adjacent low terraces. Waynesboro soils have red clayey B horizons, Sequatchie soils have dark brown A horizons over brown B horizon; and Whitwell soils have gray mottles in the B horizon.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; moderate permeability.
USE AND VEGETATION: Mostly cleared and used for general farm crops including small grains, tobacco, cotton, hay, and pasture. Originally, forests were mixed hardwoods and pines chiefly oak species, hickory, dogwood, yellow-poplar, elm, beech, and shortleaf, loblolly, and Virginia pines.
DISTRIBUTION AND EXTENT: Great Valley and Highland Rim areas in Tennessee, northern Alabama, northwestern Georgia, and Boston Mountains area of Arkansas. The series is of large extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Morgantown, West Virginia
SERIES ESTABLISHED: Grainger County, Tennessee; 1905.
REMARKS: Diagnostic horizons recognized in this pedon are:
Ochric epipedon - from 0 to 8 inches (Ap horizon)
Argillic horizon - from 14 to 75 inches (Bt1 - Bt4 horizons)