LOCATION COTACO KY+TN VA WVEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, semiactive, mesic Aquic Hapludults
TYPICAL PEDON: Cotaco loam--cultivated--on a smooth concave 1 percent slope. (Colors are for moist soil.)
Ap--0 to 10 inches; dark grayish brown (10YR 4/2) loam; weak fine granular structure; very friable; many fine roots; about 2 percent pebbles; slightly acid; abrupt smooth boundary. (5 to 12 inches thick)
BA--10 to 16 inches; yellowish brown (10YR 5/4) sandy clay loam; weak medium subangular blocky structure; friable; many fine roots; many fine pores; many faint brown (10YR 5/3) iron depletions on ped faces and common medium prominent strong brown (7.5YR 5/6) iron concentrations throughout; few patchy clay films on peds; about 5 percent pebbles; slightly acid; gradual smooth boundary. (0 to 10 inches thick)
Bt1--16 to 23 inches; yellowish brown (10YR 5/4) gravelly sandy clay loam; weak medium subangular blocky structure; friable; thin clay films on peds; common medium prominent light brownish gray (2.5Y 6/2) iron depletions and common medium distinct brown (7.5YR 4/4) and yellowish brown (10YR 5/8) iron concentrations throughout; 15 percent sandstone and shale pebbles and thin flat channers; strongly acid; gradual smooth boundary. (5 to 25 inches thick)
Bt2--23 to 41 inches; grayish brown (2.5Y 5/2) gravelly clay loam; moderate medium subangular blocky structure; friable; thin clay films; many prominent yellowish brown (10YR 5/8) and brown (7.5YR 4/4) iron concentrations throughout; about 30 percent pebbles and dark reddish brown iron and manganese concretions; strongly acid; gradual smooth boundary. (0 to 30 inches thick)
C1--41 to 46 inches; yellowish brown (10YR 5/4) gravelly clay loam; massive; friable; many medium distinct brown (7.5YR 4/4) iron concentrations and light brownish gray (10YR 6/2) iron depletions throughout; about 40 percent pebbles and iron and manganese concretions; strongly acid; gradual smooth boundary. (0 to 20 inches thick)
C2--46 to 66 inches; yellowish brown (10YR 5/6) sandy clay loam; massive; slightly sticky; many fine and medium prominent gray (10YR 6/1) iron depletions and brown (7.5YR 4/4) iron concentrations throughout; 5 percent pebbles; strongly acid.
TYPE LOCATION: Greenup County, Kentucky; on a tributary of East Fork Creek 1/4 mile east of KY 503, and 1 1/4 mile south of junction of KY 207 and KY 503.
RANGE IN CHARACTERISTICS: The solum thickness ranges from 30 to 60 inches, and depth to bedrock is more than 60 inches. Fragments of gravel-sized sandstone, shale, or siltstone range from 0 to 35 percent in the solum, and from 0 to 50 percent in the
C horizon. Unless limed, the reaction ranges from strongly acid to extremely acid.
The A horizon has hue of 10YR or 7.5YR, value of 4 or 6, and chroma of 2 to 4. Fine-earth texture is loam, silt loam, or fine sandy loam. Some pedons have A horizons that have value of 3, but these horizons are generally less than 7 inches thick.
The Bt horizon has hue of 2.5Y to 5YR, value of 4 to 6, and chroma of 3 to 8. Fine-earth texture is silt loam, loam, clay loam, silty clay loam, or sandy clay loam. Redoximorphic features are in shades of gray, brown, and red.
Some pedons have BC horizons with colors like the Bt horizon, and others have lower Btg or BCg horizons that are gleyed. A few pedons have 2B horizons in the lower solum.
The C, Cg or 2C horizon, where present, has hue of 7.5YR to 2.5Y, value of 4 through 8, and chroma of 1 through 8, or is neutral with value of 4 through 8. These horizons are often variegated with redoximorphic features in shades of gray, brown and red, without a clearly dominant matrix color. Fine-earth texture is silt loam, loam, clay loam, silty clay loam, or sandy clay loam. The C horizons in some pedons are stratified.
COMPETING SERIES: These are Adelphia, Blairton, Holmdel, Kensington, Trackler, Wharton, Whiteside, and Woodstown series in the same family, and the Delanco, Dillard and tentative Russet series, differing only in cation-exchange activity class. Additionally, series that have not been assigned an activity class include Bigpool, Fenwick and Tuscarawas. Adelphia, Holmdel, Russet, and Woodstown formed from marine, fluvio-marine, or deltaic parent materials. Adelphia and Holmdel soils also contain glauconite. Russett and Woodstown soils also contain quartz pebbles or ironstone fragments. Bigpool overlaps the Cotaco series considerably but generally has a more shallow solum range, lower rock fragment content range and does not allow 2.5Y hues. Blairton and Fenwick are less than 40 inches to bedrock. Delanco, Dillard, and Whiteside are derived from crystalline rocks and have flakes of mica. Kensington soils have a lithologic discontinuity consisting of glacial till over residuum. Trackler soils formed from material weathered from fine-grained igneous rocks and are less than 60 inches to bedrock. Tuscarawas soils have a lithologic discontinuity and have clayey textures in the substratum. Wharton soils are formed from sedimentary residuum and generally have more silt.
GEOGRAPHIC SETTING: Foot slopes, colluvial fans, and low stream terraces with slopes of 0 to 20 percent. The regolith is alluvium of acid sandstone, siltstone, and shale origin. Near the type location, the average annual precipitation is 42 to 54 inches, and average annual air temperature is 47 to 57 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are Allegheny and Monongahela series on stream terraces, Pope and Stendal series on flood plains, and Dekalb, Jefferson, and Shelocta series of the surrounding uplands. Allegheny, Jefferson, and Shelocta soils lack redoximorphic depletions in the upper 24 inches of the argillic horizon. Monongahela soils have a fragipan. Dekalb, Pope, and Stendal soils lack argillic horizons.
DRAINAGE AND PERMEABILITY: Moderately well or somewhat poorly drained. Permeability class is moderate. Runoff class is high or very high in soils with shallow seasonal free water, and negligible to medium where seasonal free water is deeper. Seepage areas are common.
USE AND VEGETATION: Largely used for crops, principally corn, burley, tobacco, small grains, truck, fruit, sorghum, and hay or pasture. Native forest has oak, hickory, elm, beech, sourwood, blackgum, and yellow-poplar as the dominant species.
DISTRIBUTION AND EXTENT: Primarily the Cumberland and Allegheny Plateaus in Kentucky, Tennessee, Virginia, and West Virginia, and the Northern Appalachian Ridges and Valleys in Virginia. Extent is moderate.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Morgantown, West Virginia
SERIES ESTABLISHED: Jackson County, Alabama; 1944.
REMARKS: The 4/2002 revision updates this series to 8th edition Keys to Soil Taxonomy standards. Redoximorphic feature terminology and competing series were also updated at this time. Cation-exchange class placement is based on both pedon S78KY-121-3 and on geographically related soils such as Allegheny. The CEC/clay ratio of .27 for this pedon indicates a semiactive class.
Diagnostic horizons and features recognized in this pedon are:
a. Ochric epipedon - The zone from the surface of the soil to a depth of approximately 10 inches (Ap horizon).
b. Argillic horizon - The zone from approximately 10 to 41 inches (BA, Bt1, Bt2 horizons).
c. Redoximorphic features - occurring within 24 inches of the top of the argillic horizon (Aquic subgroup).
Laboratory data for the series includes pedon S78KY-121-3, analyzed by the University of Kentucky.
MLRAs: 124, 125, 126, 127 and 147.
Revised: 4/94-JHN, CWH, JMR; 4/2002-ABJ, DHK