LOCATION REDCO TXEstablished Series
TAXONOMIC CLASS: Very-fine, smectitic, thermic Chromic Dystruderts
TYPICAL PEDON: Redco clay--forested. (Colors are for moist soil unless otherwise stated.)
A--0 to 7 inches; very dark grayish brown (10YR 3/2) clay, dark grayish brown (10YR 4/2) dry; moderate fine subangular blocky structure; very hard, firm; many medium and coarse roots; few fine pores; slightly acid; clear smooth boundary. (1 to 10 inches thick)
Bw--7 to 18 inches; light brownish gray (10YR 6/2) clay, light gray (10YR 7/2) dry; common medium distinct strong brown (7.5YR 5/6) mottles; moderate fine subangular blocky structure; very hard, very firm; many medium and coarse roots; few fine pores; very strongly acid; clear smooth boundary. (5 to 15 inches thick)
Bss1--18 to 40 inches; light gray (2.5Y 7/2) clay, light gray (2.5Y 7/2) dry; common medium distinct strong brown (7.5YR 5/8) mottles; moderate fine structure; very hard, very firm; many medium and coarse roots; many coarse shiny pressure faces; common intersecting slickensides; few fine black concretions; strongly acid; clear smooth boundary. (10 to 25 inches thick)
Bss2--40 to 52 inches; grayish brown (10YR 5/2) clay, light brownish gray (10YR 6/2) dry; few to common fine and medium distinct reddish brown (2.5YR 4/4) mottles; moderate medium blocky structure; very hard, very firm, sticky and plastic; few fine and medium roots; common intersecting slickensides; slightly acid; clear smooth boundary. (10 to 30 inches thick)
Bss3--52 to 72 inches; light gray (2.5Y 7/2) clay, light gray (2.5Y 7/2) dry; many medium distinct yellowish brown (10YR 5/4) mottles; moderate medium and coarse blocky structure; very hard, very firm, sticky and plastic; few fine and medium roots; few fine concretions of calcium carbonate; few coarse slickensides; slightly alkaline.
TYPE LOCATION: Walker County, Texas; 3.7 miles east of the Walker County Courthouse in Huntsville, Texas, on U.S. Highway 190; then south on Farm Road 2929 and the Fournotch Road for 10.3 miles; then east on fire land road 500 feet and north 325 feet in the woods.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 60 to 80 inches. The weighted average clay content of the particle-size control section ranges from 60 to 70 percent. When dry, cracks 1/2 to more than 1 inch wide extend from the surface to a depth of more than 12 inches. Cracks remain open from 60 to 90 cumulativee days in most years. Skickensides and wedge-shaped peds begin at a depth of 10 to 24 inches. Undisturbed areas gave gilgai microrelief with microknolls about 4 to 12 inches above the microdepression. Distance from the center of the microkknoll to the center of the microdepression ranges from 8 to 15 feet. Colors with chroma of 2 or less in the subsoil are conidered to be lith-chromic. Mottles with chroma of 3 or more, or redox concentrations, are considered to be relic or litho-chromic.
The A horizon has colors of brown hue of 10YR or 7.5YR, value of 3 through 5, and chroma of 2 through 4. Mottles in shades of brown, yellow, and red range from none to common. It ranges from strongly acid through slightly acid.
The Bss1 and Bss2 horizons have colors of gray or brown hue of 10YR or 2.5YR, value of 5 through 7, and chroma of 2 through 4. Mottles range from few to many in shades of brown, yellow, olive, and red. Reaction ranges from very strongly acid to modetately acid, but it is very strongly acid throughout more than half of the upper 20 inches.
The Bss3 horizon has colors of the upper Bs horizons. Concretions of calcium carbonate range from none to common. The reaction is moderately acid to slightly alkaline.
COMPETING SERIES: These are the Burkeville and Tahoula series in the same family and the similar Lacerda, Naclina, Raylake, and Woodville series. Burkeville soils are calcareous throughout. Lacerda and Raylake soils contain a horizon that is prominently mottled with with red or yellowish red. Burkeville soils are calcareous to the surface and have colors in hue 10YR to 5Y. Tahoula soils are deep to tuffaceous material. Lacerda and Raylake soils are more acid. Woodville soils have a Bt horizon.
GEOGRAPHIC SETTING: Redco soils occupy nearly level to gently sloping low uplands. Slopes range from 0 to 5 percent. Redco soils formed in acid to alkaline clayey sediments. Climate is warm and humid. At the type location, the mean annual precipitation is about 45 inches. Mean annual temperature is 67 degrees F., and Thornthwaite P-E index is 70.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Annona, Leson, Lufkin, Wiergate, and Woodville series. Annona, and Lufkin soils have loamy surface layers. argillic horizons, and are on similar landscape positions. Leson and Wiergate soils have chroma of less than 1.5 throughout the upper 12 inches of the soil. Woodville soils have argillic horizons and are on slightly higher positions.
DRAINAGE AND PERMEABILITY: Moderately well drained; very slow runoff; very slow internal drainage; very permeability. The soil is wet for several months during the rainy season each year.
USE AND VEGETATION: Used mainly for forest and pasture. Forested areas are mainly loblolly and shortleaf pine. post oak, water oak, willow oak, and sweetgum. Grasses are mainly species of andropogon, paspalum, and panicum. Small areas are cultivates to cotton, soybeans, row feeds, and small grains.
DISTRIBUTION AND EXTENT: The Texas Claypan and Southern Coastal Plain of Southeast Texas. Series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Walker County, Texas; 1975.
REMARKS: The soils were previously included in the Garner series. Formerly classified as Aquentic Chromuderts. 1/94 Series was reclassified from a Hapludert to a Dystrudert in 10/2001 based on lab data from the type location and other pedons.
Diagnostic Horizons:
Ochric epipedon - 0 to 7 inches.
Cambic Horizon - 7 to 72 inches.