LOCATION ROEBUCK OK+LA TXEstablished Series
TAXONOMIC CLASS: Fine, smectitic, thermic Aeric Epiaquerts
TYPICAL PEDON: Roebuck clay--forested. (Colors are for moist soil unless otherwise stated.)
A--0 to 10 inches; dark reddish brown (5YR 3/3) clay, reddish brown (5YR 5/3) dry; common fine distinct yellowish red redoximorphic concentration masses; moderate medium and fine granular structure; very hard, firm; common fine roots; few wormcasts; slightly acid; gradual smooth boundary. (5 to 20 inches thick)
Bw--10 to 45 inches; dark reddish brown (5YR 3/3) clay, reddish brown (5YR 4/3) dry; common fine distinct yellowish red redoximorphic concentration masses; weak medium and coarse blocky structure; very hard, firm; common fine roots; few wormcasts; few slickensides; few fine dark concretions; slightly acid; gradual smooth boundary. (10 to 40 inches thick)
C--45 to 72 inches; reddish brown (5YR 4/4) clay, reddish brown (5YR 5/4) dry; common fine distinct yellowish red redoximorphic concentration masses and few fine distinct gray redoximorphic depletion masses; massive; very hard, firm; few roots; mildly alkaline.
TYPE LOCATION: Okmulgee County, Oklahoma; about 1/2 mile west of Okmulgee; about 200 feet south and 200 feet west of the northeast corner of sec. 11, T. 13 N., R. 12 E.
RANGE IN CHARACTERISTICS: All horizons range from slightly acid through moderately alkaline. Depth to secondary carbonates is greater than 40 inches. Some pedons have buried A horizons below 2 feet.
The A horizon has hue of 2.5YR to 10YR, value of 2 or 3, and chroma of 2 or 3. Redoximorphic concentration masses are in shades of brown or red. This horizon is clay loam, silty clay loam, clay, or silty clay.
The Bw horizon has hue of 2.5YR or 5YR, value of 3 to 5, and chroma of 2 to 6 or hue of 7.5YR, value of 3 or 4, and chroma of 2 to 4. Redoximorphic concentration masses are in shades of brown or red. This horizon is mainly clay or silty clay, but includes clay loam or silty clay loam. The clay content ranges from 35 to 60 percent.
The C horizon is similar in texture and color to the Bw horizon. Redoximorphic concentration masses are in shades of brown or red or redoximorphic depletion masses in shades of gray. Some pedons have a 2C layer stratified with thin layers of silt loam, loam, or fine sandy loam.
COMPETING SERIES: Their are no competing series in the same family.
GEOGRAPHIC SETTING: Roebuck soils occur on level to slightly concave flood plains. Slopes are 0 to 1 percent. They have formed in clayey or loamy alluvium derived mostly from Permian red beds. They are subject to flooding for brief to very long periods during the months of January through July. The climate is moist subhumid to humid; Thornthwaite annual P-E index ranges from 60 to 80; average annual precipitation ranges from 37 to 45 inches; mean annual temperature ranges from 57 to 64 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Boxville, Caspiana, Garton, Karma, Kiomatia, Latanier, Moreland, Oklared, Pledger, Redlake, Redport, Ships, and Whakana series. The Boxville, Karma, and Whakana soils are on distinct higher terraces above flooding and they have an argillic horizon. Caspiana and Garton soils are on slightly higher terraces and have an argillic horizon. Kiomatia and Oklared soils are on lower flood plains and terraces. Kiomatia soils are sandy and Oklared soils are coarse-loamy. Latanier, Moreland, Redlake, Redport, and Ships soils are usually on the same terrace but slightly higher on the landscape and closer to the main stream. Pledger soils are on similar landscapes but the parent material in upper part of the pedon has been derived from sources other than Permian red beds. Redport soils are fine-silty.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained; runoff is high on level surfaces and negligible on concave surfaces; permeability is very slow. Some area are ponded for long periods from 0 to 1.0 foot following wet periods from October to June.
USE AND VEGETATION: Roebuck soils are used for growing cotton, soybeans, wheat, grain sorghum, and tame pasture. Some areas are used for native range, forest, or wildlife. Native vegetation is bottomland hardwoods with an understory of grasses.
DISTRIBUTION AND EXTENT: Western Arkansas, Louisiana, central and eastern Oklahoma, and eastern Texas. The series is moderately extensive.
MLRA OFFICE RESPONSIBLE: Little Rock, Arkansas
SERIES ESTABLISHED: Choctaw County, Oklahoma; 1940.
REMARKS: Soil Interpretation Record: Series OK0164
Diagnostic horizons and features recognized in this pedon are: Mollic epipedon- the zone from the soil surface to a depth of 45 inches (the A and Bw horizons); Episaturation; Cambic horizon - the zone from 10 inches to a depth of 45 inches (the Bw horizon).