LOCATION DELWIN TX+OKEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, active, thermic Typic Paleustalfs
TYPICAL PEDON: Delwin fine sand - cropland. (Colors are for dry soil unless otherwise stated.)
Ap--0 to 5 inches; light brownish gray (10YR 6/2) fine sand, dark grayish brown (10YR 4/2) moist; single grained; loose; slightly acid; clear smooth boundary. (0 to 15 inches thick)
E--5 to 16 inches; brown (7.5YR 5/4) fine sand, brown (7.5YR 4/4) moist; single grained; loose; slightly acid; abrupt wavy boundary. (5 to 17 inches thick)
Bt1--16 to 32 inches; reddish brown (5YR 4/4) sandy clay loam, dark reddish brown (5YR 3/4) moist; moderate medium prismatic structure parting to moderate medium subangular blocky structure; very hard, friable; pockets and streaks of clean sand grains; dark clay films on vertical faces of prisms; few fine quartz pebbles; neutral; diffuse smooth boundary. (10 to 24 inches thick)
Bt2--32 to 45 inches; yellowish red (5YR 5/6) sandy clay loam, yellowish red (5YR 4/6) moist; moderate medium subangular blocky structure; very hard, friable; sand grains coated and bridged with clay; few fine quartz pebbles; neutral; diffuse smooth boundary. (8 to 22 inches thick)
Bt3--45 to 60 inches; yellowish red (5YR 5/6) sandy clay loam, yellowish red (5YR 4/6) moist; moderate fine subangular blocky structure; hard, friable; few distinct clay films on surfaces of peds and bridging sand grains; neutral; gradual smooth boundary. (9 to 22 inches thick)
Bt4--60 to 72 inches; yellowish red (5YR 5/6) sandy clay loam, yellowish red (5YR 4/6) moist; moderate fine subangular blocky structure; hard, friable; few distinct clay films on surface of peds and bridging sand grains; few pockets of loamy sand; neutral; gradual smooth boundary. (0 to 15 inches thick)
BC--72 to 80 inches; yellowish red (5YR 5/6) sandy clay loam, yellowish red (5YR 4/6) moist; weak medium subangular blocky structure; hard, friable; with alternating bands of C material that is reddish yellow (5YR 7/6) sandy loam, reddish yellow (5YR 6/6) moist; structureless; loose; neutral.
TYPE LOCATION: Wheeler County, Texas; from the railroad crossing in Allison (northeast corner of county), 0.3 mile east on county road, 0.9 mile south and 265 feet west in a cultivated field. (from the southeast corner of sec. 21, Robertson and Eddleman Survey, 264 feet west and 100 feet north).
RANGE IN CHARACTERISTICS: Thickness of solum exceeds 80 inches. Depth to secondary carbonates, where present, is greater than 60 inches.
The A horizon has hue of 5YR to 10YR, value of 4 to 7, and chroma of 2 to 4. Texture is sand, loamy sand or fine sand. Loamy fine sand texture is present where plowing has mixed the surface with underlying material. Reaction is slightly acid or neutral.
The Bt horizon has hue of 2.5YR to 7.5YR, value of 4 to 7, and chroma of 3 to 8. Texture is sandy clay loam or fine sandy loam with clay content of 18 to 35 percent in the upper part and 15 to 30 percent in the lower part. Clean sand grains are present on prism faces in Bt1 horizons of some pedons. Reaction is neutral or slightly alkaline.
The BC horizon has color in shades of red, yellow, or brown. The B material has lamellae of sandy clay loam alternating with sandy loam. The C material is mostly sandy loam. Some pedons have prismatic structure that has clean sand on prism surfaces up to 6 mm thick. Reaction ranges from neutral to moderately alkaline.
COMPETING SERIES: These are the Miles and Seagraves(T) series. Similar soils are the Decobb(T), Grandfield, Grandmore, Menard, Rochelle, and Springer series. Miles soils have secondary carbonates within a depth of 37 to 60 inches. Seagraves soils have a calcic horizon at depths of 50 to 80 inches. Decobb soils are underlain by weakly consolidated sandstone below 60 inches. Grandfield and Menard soils have a decrease in clay content from maximum by more than 20 percent within a depth of 60 inches without skeletans or other evidence of eluviation in the zone of clay decrease. Grandmore soils have a discontinuity in the lower part of the solum with a clay increase and low chroma iron depletion colors. Rochelle soils have a gravelly substratum within 60 inches. Springer soils have a coarse-loamy particle-size control section.
GEOGRAPHIC SETTING: The Delwin soils are on nearly level to moderately sloping wind reworked sandsheets on terraces on uplands. Slopes are mostly convex and less than 3 percent but range to 8 percent. The soil formed in sandy and loamy ancient alluvium apparently reworked by wind. Mean annual precipitation is 20 to 25 inches and mean annual temperature is 57 to 64 degrees F. Frost free days range from 190 to 230 days and elevation ranges from 1,500 to 2,550 feet. Thornthwaite P-E index ranges from 30 to 44.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Miles and the Anson, Devol, Eda, Grandfield, Heatly, Nobscot, and Springer series. Miles, Grandfield, and Springer soils occur in similar positions. Anson, Heatly and Nobscot soils have sandy surfaces more than 20 inches thick (arenic) and occur on slightly higher positions. Devol soils occur on similar surfaces and have a coarse-loamy particle-size control section. Eda soils occur on slightly higher areas and have a sandy particle-size control section.
DRAINAGE AND PERMEABILITY: Well drained. Permeability is moderate.
Runoff is negligible on 0 to 1 percent slopes;; low on 1 to 5 percent slopes and medium on 5 to 8 percent slopes.
USE AND VEGETATION: Large areas are cropped to both irrigated and dryland cotton, grain sorghum, alfalfa and small grains. Native vegetation consists of little bluestem, sand bluestem, switchgrass, sideoats grama, and sand dropseed. Shinnery oak, sand sagebrush, juniper and mesquite have invaded some areas.
DISTRIBUTION AND EXTENT: Central Rolling Red Plains (MLRA 78B, 78C) of Texas and Oklahoma. The series is of moderate extent.
MLRA OFFICE RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Cottle County, Texas; 1970.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - the zone from the surface to about 16 inches (Ap and E horizons)
Argillic horizon - the zone from 16 to 72 inches (Bt1, Bt2, Bt3 and Bt4 horizons)
Pale feature - The clay content does not decrease by as much as 20 percent of the maximum within 60 inches.
Soil Interpretation Record: TX0399