LOCATION STEPHENVILLE OK KS TX

Established Series
Rev. CRC:CS:CEW:WJG
02/2014

STEPHENVILLE SERIES

The Stephenville series consists of moderately deep, well drained, soils formed in material weathered from sandstone of Permian age. These soils are on very gently sloping to moderately steep side slopes of hills in the North Cross Timbers (MLRA 84A). Slopes range from 1 to 25 percent. Mean annual precipitation is about 810 mm (32 inches). Mean annual air temperature is about 16 degrees C (61 degrees F).

TAXONOMIC CLASS: Fine-loamy, siliceous, active, thermic Ultic Haplustalfs

TYPICAL PEDON: Stephenville loamy fine sand, on a east-facing, convex, 5 percent slope in bermuda grass pasture, at an elevation of 375 m (1,230 feet). (Colors are for dry soil unless otherwise stated.)

A--0 to 13 cm (0 to 5 inches); grayish brown (10YR 5/2) loamy fine sand, very dark grayish brown (10YR 3/2) moist; weak very fine granular structure; soft, very friable; many very fine and fine and few medium and coarse roots; moderately acid; clear smooth boundary. (8 to 20 cm [3 to 8 inches] thick)

E--13 to 38 cm (5 to 15 inches); light brown (7.5YR 6/4) loamy fine sand, brown (7.5YR 5/4) moist; weak fine granular structure; soft, very friable; common very fine and fine and few medium roots; strongly acid; abrupt wavy boundary. (0 to 33 cm [0 to 13 inches] thick)

Bt1--38 to 64 cm (15 to 25 inches); red (2.5YR 5/6) sandy clay loam, red (2.5YR 4/6) moist; moderate medium subangular blocky structure; very hard, firm; common very fine and fine and few medium roots; common distinct continuous clay films on faces of peds; clean sand grains along root channels; strongly acid; gradual wavy boundary.

Bt2--64 to 84 cm (25 to 33 inches); light red (2.5YR 6/6) sandy clay loam, red (2.5YR 5/6) moist; weak coarse subangular blocky structure; hard, firm; few very fine and medium, common fine and very few coarse roots; common distinct patchy clay films on faces of peds; clean sand grains along root channels; strongly acid; clear wavy boundary. (Combined thickness of Bt horizon is 33 to 76 cm [13 to 30 inches])

Cr1--84 to 102 cm (33 to 40 inches); red (2.5YR 5/6) weakly cemented fine-grained sandstone, red (2.5YR 4/6) moist; common fine and few medium roots in fractures; strongly acid; clear wavy boundary.

Cr2--102 to 130 cm (40 to 51 inches); light red (2.5YR 6/8) weakly cemented fine-grained sandstone, red (2.5YR 5/8) moist; common fine and few medium roots in fractures; strongly acid.

TYPE LOCATION: Oklahoma County, Oklahoma; about 2.5 miles east and 1 mile north of Spencer, Oklahoma; located about 750 feet south and 450 feet east of the northwest corner of sec. 8, T. 12 N., R. 1 W. Spencer, OK USGS Topographic Quadrangle; Latitude 35 degrees, 32 minutes, 6 seconds N; Longitude 97 degrees, 20 minutes, 2.4 sec. W. NAD 83.

RANGE IN CHARACTERISTICS:
Depth to paralithic contact: 51 to 102 cm (20 to 40 inches)

A horizon
Hue: 5YR to 10YR
Value: 3 to 5 moist, 5 to 7 dry
Chroma: 2 to 6 moist or dry
Texture: loamy fine sand or fine sandy loam
Reaction: strongly acid to slightly acid (upper part of the A horizon of some pedons are neutral due to liming)

E horizon
Hue: 5YR to 10YR
Value: 4 to 6 moist, 5 to 7 dry
Chroma: 2 to 6 moist or dry
Texture: loamy fine sand or fine sandy loam
Reaction: strongly acid to slightly acid

Bt horizon
Hue: 2.5YR or 5YR
Value: 4 to 6 moist, 5 to 7 dry
Chroma: 3 to 8 moist or dry
Texture: fine sandy loam or sandy clay loam
Reaction: very strongly acid to slightly acid

BC horizon (where present)
Hue of 2.5YR or 5YR
Value: 4 or 5 moist, 5 or 6 dry
Chroma: 4 to 8 moist or dry
Texture: fine sandy loam or sandy clay loam
Coarse fragments: sandstone, less than 76 mm (3 inches) in diameter.
0 to 35 percent by volume
Reaction: very strongly acid to slightly acid

Cr horizon
Hue: 2.5YR or 5YR
Value: 4 or 6 moist, 5 to 7 dry
Chroma: 4 to 8 moist or dry
Paralithic contact: Weakly cemented sandstone. Root restrictive with fractures greater than 10 cm (4 inches) apart.

COMPETING SERIES: These are the, Littleaxe and Weatherford series in the same family. These soils are greater than 102 cm (40 inches) to paralithic contact.

GEOGRAPHIC SETTING:
Parent material: Materials weathered from sandstone of Permian age.
Landscape: Uplands
Landform: Hills
Geomorphic Component: Side slopes
Hillslope Position: Backslopes
Slopes: 1 to 25 percent
Mean annual precipitation: 760 to 1015 mm (30 to 40 inches)
Mean annual air temperature: 13 to 17 degrees C (56 to 63 degrees F)
Frost-free period: 200 to 250 days
Elevation: 229 to 395 meters (750 to 1295 feet)
Thornthwaite annual P-E indices: 48 to 64

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Darnell, Darsil, Harrah, Konawa, and the competing Littleaxe soils.
Darnell and Darsil soils: Less than 50 cm (20 inches) to paralithic contact and occur on crests.
Harrah soils: Greater than 150 cm (60 inches) to paralithic contact and occur on base slopes.
Konawa soils: Greater than 150 cm (60 inches) to paralithic contact and occur on stream terraces.
Littleaxe soils: Occur on similar landform positions.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained. Runoff is low on 1 to 5 percent slopes, medium on 5 to 20 percent slopes and high on slopes greater than 20 percent. Saturated hydraulic conductivity is moderately high in the most restrictive layer above paralithic contact.

USE AND VEGETATION: Used for rangeland. Some areas used for cropland and tame pasture. Native vegetation is mainly post oak, blackjack oak, hickory, and eastern red cedar with an understory of tall and mid grasses. Cultivated crops include grain sorghums, small grains, and peanuts.

DISTRIBUTION AND EXTENT: Central Oklahoma. Land Resource Region H. MLRA 84A (Northern Cross Timbers). The series is extensive.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas.

SERIES ESTABLISHED: Eastland County, Texas; 1916.

REMARKS: Major changes in the OSD were made by Walt Schaefer, as a result of the Soil Data Join Re-correlation Initiative (SDJR) in 06/2013.

Diagnostic horizons and features recognized in this pedon are:

Ochric epipedon - 13 cm (5 inches) (A horizon).

Albic materials (less than 85 percent by volume) - 13 to 38 cm (5 to 15 inches). (E horizon)

Argillic horizon - 38 to 84 cm (15 to 33 inches). (Bt horizons)

Paralithic contact - Sandstone bedrock at a depth of 84 cm (33 inches). (Cr horizon)

ADDITIONAL DATA: Soil Survey Investigation Report No. 11, May 1967, National Soil Survey Lab. Lab No. 17174-17179, 17180-17185, S89OK-083-003, and S91OK-109-002; Oklahoma State University Lab No. 70-OK-55-1.

Taxonomic Version: USDA-NRCS, Keys to Soil Taxonomy, Eleventh Edition, 2010.

National Cooperative Soil Survey
U.S.A.