LOCATION SHREWDER OK+TXEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, thermic Typic Haplustepts
TYPICAL PEDON: Shrewder fine sandy loam, on a 1.5 percent slope cultivated to wheat. (Colors are for dry soil unless otherwise stated.)
Ap--0 to 8 inches; reddish brown (5YR 5/4) fine sandy loam, reddish brown (5YR 4/4) moist; weak medium granular structure; slightly hard, very friable; few fine roots; slightly acid; abrupt smooth boundary. (6 to 11 inches thick)
A--8 to 16 inches; reddish brown (5YR 5/4) fine sandy loam, reddish brown (5YR 4/4) moist; weak fine subangular blocky structure; slightly hard, friable; few fine roots; neutral; gradual smooth boundary. (0 to 10 inches thick)
Bw1--16 to 31 inches; red (2.5YR 4/6) loam, dark red (2.5YR 3/6) moist; weak coarse prismatic structure parting to weak medium subangular blocky; slightly hard, friable; few fine roots; neutral; gradual smooth boundary. (13 to 42 inches thick)
Bw2--31 to 49 inches; red (2.5YR 5/6) loam, red (2.5YR 4/6) moist; weak coarse prismatic structure parting to weak medium subangular blocky; slightly hard, very friable; few fine roots; slightly alkaline; gradual smooth boundary. (0 to 22 inches thick)
2BCk--49 to 77 inches; red (2.5YR 5/6) very fine sandy loam, red (2.5YR 5/6) moist; weak coarse prismatic structure; slightly hard, very friable; few fine roots; few fine and medium nodules and masses of calcium carbonate; few threads and films of calcium carbonate; strongly effervescent; moderately alkaline; gradual smooth boundary. (0 to 37 inches thick)
2Cd--77 to 80 inches; red (2.5YR 5/6) noncemented sandstone bedrock; common films of calcium carbonate in seams; moderately alkaline.
TYPE LOCATION: Harmon County, Oklahoma; about 1 3/4 miles southwest of Vinson; 900 feet north and 700 feet east of the southwest corner of sec. 19, T. 5 N., R. 25 N.; Latitude: 34 degrees, 53 minutes, 18 seconds N; Longitude: 99 degrees, 53 minutes, 09 seconds W. Madge, OK topographic quadrangle; NAD 1927.
RANGE IN CHARACTERISTICS:
Particle-size control section (weighted average)
Clay content: 10 to 18 percent
Coarse Fragments: 0 to 1 percent
CEC/clay ratio: more than 0.6
Depth to densic sandstone: 60 to more than 80 inches
Thickness of the solum, 60 to more than 80 inches
Depth to secondary calcium carbonate: 28 to 60 inches
A Horizon
Hue: 5YR or 7.5YR
Value: 4 or 5
Chroma: 3 or 4
Texture: very fine sandy loam, fine sandy loam, or loam
Effervescence: noneffervescent
Reaction: slightly acid to slightly alkaline (6.1-7.8)
Bw Horizon
Hue: 2.5YR or 5YR
Value: 4 or 5
Chroma: 4 to 6
Texture: very fine sandy loam, fine sandy loam, or loam
Clay content: 10 to 18 percent
Coarse fragments: 0 to 1 percent
Calcium carbonate equivalent: 0 to 5 percent
Effervescence: noneffervescent to slightly effervescent
Reaction: neutral to moderately alkaline (6.6-8.4)
BC Horizon
Hue: 2.5YR or 5YR
Value: 4 to 6
Chroma: 6 to 8
Texture: very fine sandy loam, fine sandy loam, or loam
Clay content: 10 to 18 percent
Coarse fragments: 0 to 1 percent
Calcium carbonate equivalent: 1 to 10 percent
Effervescence: noneffervescent to strongly effervescent
Reaction: slightly or moderately alkaline (7.4-8.4)
C Horizon, where present
Hue: 2.5YR or 5YR
Value: 4 to 6
Chroma: 6 to 8
Texture: very fine sandy loam, fine sandy loam, loam, or loamy fine sand
Clay content: 5 to 18 percent
Coarse fragments: 0 to 1 percent
Calcium carbonate equivalent: 1 to 10 percent
Effervescence: slightly to strongly effervescent
Reaction: slightly to moderately alkaline
The 2Cd horizon is reddish noncemented sandstone. Calcium carbonate equivalent ranges from 1 to 8 percent. Fractures are greater than 10 cm apart. The bulk density is high enough to be root restrictive. This material has moderate to high excavation difficulty. Most of this material slakes in water within 15 hours.
COMPETING SERIES: These are
Dill,
Hardeman and
Hext series in the same family.
Dill : These soils sandstone bedrock between 20 to 40 inches.
Hardeman and Hext : These soils have secondary calcium carbonates within 28 inches of the soil surface.
GEOGRAPHIC SETTING:
Parent material: loamy alluvium of Pleistocene age over residuum from sandstone of Permian age
Landform: treads and risers of stream terraces on alluvial plain remnants
Slope: 1 to 8 percent
Mean annual air temperature range: 57 to 64 degrees F.
Mean annual precipitation range: 22 to 30 inches
Frost-free period: 185 to 230 days
Elevation: 1400 to 2100 feet
Thornthwaite annual P-E indices: 33 to 44
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Dodson,
Grandfield,
Hardeman,
Madge,
Paducah, and
Woodward series.
Dodson : These soils have a fine particle-size class, a mollic epipedon, and occur on adjacent less sloping areas.
Hardeman : These soils have secondary calcium carbonates within 28 inches of the soil surface and occur on lower side slopes.
Grandfield and Madge : These soils have a fine-loamy particle-size class, and occur on similar areas.
Paducah : These soils have a fine-silty particle-size class and occur on higher landscape positions.
Woodward : These soils have a coarse-silty particle-size class, bedrock between 20 and 40 inches, and occur on higher summits and lower side slopes.
DRAINAGE AND PERMEABILITY: Well drained; moderately rapid permeability. Runoff is very low on 1 to 5 percent slopes and low on 5 to 8 percent slopes. Depth to a water table is more than 20 feet.
USE AND VEGETATION: Soils are mainly cultivated. Cotton, wheat, sorghums, alfalfa, improved bermudagrass, and weeping lovegrass are the main crops. Native vegetation consists of mid and short grasses.
DISTRIBUTION AND EXTENT: Central Rolling Red Plains (MLRA-78B, 78C) of western Oklahoma and Texas. The series is of minor extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Harmon County, Oklahoma; 1982.
REMARKS: Soil Interpretation Record: Series OK0273.
ADDITIONAL DATA: Oklahoma State University - Lab samples 80-OK-29-5-(1-6) and 80-OK-29-6-(1-4).
The assignment of the cation-exchange activity class is supported by laboratory data number 80-OK-29-5-(1-6) from Harmon county, OK.
Diagnostic Horizons and features recognized in this soil are:
Ochric epipedon- the zone from the surface of the soil to a depth of 16 inches (A horizons).
Cambic horizon- the zone from 16 inches to a depth of 77 inches (Bw and BC horizons).
Densic contact: The contact with noncemented sandstone bedrock at 77 inches. (2Cd horizon)
Moisture regime: Typic-Ustic.
Range Site: 078XY073OK - Sandy Prairie, 078BY088TX - Sandy loam PE 25-36
Taxonomic version: Keys to Soil Taxonomy, Ninth Edition, 2004