LOCATION DURANT OKEstablished Series
TAXONOMIC CLASS: Fine, smectitic, thermic Udertic Argiustolls
TYPICAL PEDON: Durant loam--cultivated.
(Colors are for dry soil unless otherwise stated.)
Ap--0 to 8 inches; dark grayish brown (10YR 4/2) loam, very dark grayish brown (10YR 3/2) moist; moderate fine granular structure; slightly hard, friable; medium acid; gradual smooth boundary. (6 to 12 inches thick)
BA--8 to 11 inches; brown (10YR 5/3) silty clay loam, dark brown (10YR 3/3) moist; few fine distinct reddish brown mottles; moderate fine and medium subangular blocky structure; hard, firm; medium acid; gradual smooth boundary. (3 to 8 inches thick)
Bt1--11 to 30 inches; light olive brown (2.5Y 5/4) clay, olive brown (2.5Y 4/4) moist; common medium prominent yellowish red (5YR 5/6) mottles; moderate medium subangular blocky structure; very hard, very firm; many shiny faces on peds; common dark stains; medium acid; gradual smooth boundary. (10 to 30 inches thick)
Bt2--30 to 47 inches; brown (10YR 5/3) clay, brown (10YR 4/3) moist; few fine faint light brownish gray mottles; weak medium blocky structure; very hard, very firm; many shiny faces on peds; common dark stains; neutral; gradual smooth boundary. (10 to 20 inches thick)
Bt3--47 to 64 inches; light olive brown (2.5Y 5/4) clay, olive brown (2.5Y 4/4) moist; few fine faint grayish brown mottles; weak coarse blocky structure; extremely hard, very firm; few shiny faces on peds; few fine calcium carbonate concretions; moderately alkaline.
TYPE LOCATION: Bryan County, Oklahoma; about 4 miles west and 1 mile north of Albany; 900 feet north and 150 feet east of the southwest corner of sec. 35, T. 7 S., R. 10 E.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 46 to more than 60 inches. Depth to calcium carbonate concretions or disseminated lime ranges from 30 to 59 inches.
The A horizon has hue of 7.5YR or 10YR, value of 4 or 5, and chroma of 2 or 3. Texture is loam, silt loam, or clay loam. Reaction ranges from strongly acid to slightly acid.
The BA horizon has hue of 7.5YR or 10YR, value of 4 to 6, and chroma of 2 to 4. Those pedons having high values and chromas occur where the A horizon is near the thick end of its range. The BA horizon has mottles in shades of brown, red, or yellow in most pedons. Texture is clay loam, silty clay loam, or clay. Reaction ranges from strongly acid to neutral.
The Bt1 horizon and Bt2 horizon have hue of 7.5YR to 2.5Y, value of 4 to 6, and chroma of 2 to 6. Mottles are in shades of red, yellow, brown, or gray. Some pedons have non-intersecting slickensides in the Bt2 horizon and Bt3 horizon. Reaction ranges from medium acid to mildly alkaline in the Bt1 horizon and ranges from medium acid to moderately alkaline in the Bt2 horizon. Some pedons have an exchangeable sodium percentage of 1 to 14 in the Bt2 horizon.
The Bt3 horizon has hue of 7.5YR to 2.5Y, value of 4 to 7, and chroma of 2 to 6. Mottles are in shades of red, yellow brown, or gray. Reaction ranges from slightly acid to moderately alkaline. Some pedons have an exchangeable sodium percentage of 1 to 14. Some pedons have shale at a depth below 64 inches.
COMPETING SERIES: These are Benchley, Flatonia, Foraker and Tabler series in the same family. Soils in similar families are Agan, Axtell, Aydelotte, Barbarosa, Burleson, Clarita, Crawford, Crockett, Culp, Denton, Heiden, Kirkland, Krum, Lofton, Matoy, Mosheim, Renfrow, Sanger, Tamford, and Watonga series. Agan, Axtell, Aydelotte and Crockett soils do not have a mollic epipedon. In addition, Agan and Aydelotte soils have mixed mineralogy. Barbarosa and Kirkland soils have an abrupt textural change between the A horizon and Bt horizon. Burleson, Clarita, Crawford, Heiden, Krum, Matoy, Sanger, Tamford, and Watonga soils do not have a Bt horizon. Benchley and Flatonia soils have warmer average soil temperatures and longer growing seasons. Culp and Lofton soils have mixed mineralogy. In addition, Lofton soils do not have a Bt horizon. Denton and Mosheim soils have a calcic horizon. Foraker soils have a solum less than 40 inches thick. Renfrow soils have hue of 5YR or redder in the Bt horizon. Tabler soils have a mollic epipedon more than 20 inches thick.
GEOGRAPHIC SETTING: Durant soils are on nearly level to gently sloping upland flats and slightly convex broad ridges in the Grand Prairie. Slopes are 0 to 6 percent. They formed in material weathered from clayey sediments or shale of Cretaceous age. Mean annual precipitation ranges from 32 to 42 inches. Mean annual temperature ranges from 62 to 64 degrees F. Thornthwaite annual P-E indices range from 50 to 70. Frost free days range from 210 to 230 days. Elevation ranges from 500 to 1000 feet.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Burleson, Clarita, Crockett, Heiden series and the Normangee and Wilson series. Burleson, Crockett, Normangee and Wilson soils occur on similar areas of the landscape. Normangee and Wilson soils do not have a mollic epipedon. Wilson soils have a perched water table within 1 foot of the surface. Clarita and Heiden soils usually occur on side slopes below Durant soils.
DRAINAGE AND PERMEABILITY: Moderately well drained, slow or medium runoff; very slow permeability.
USE AND VEGETATION: Used for cotton, small grains, grain sorghums, tame pasture, and range. The native vegetation is tall grass.
DISTRIBUTION AND EXTENT: Grand Prairie of Oklahoma and Texas. The series is of moderate extent.
MLRA OFFICE RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Bryan County, Oklahoma; 1906.
REMARKS: Diagnostic horizon and features in this pedon are:
Mollic epipedon 0 to 11 inches.
Argillic horizon 8 to 64 inches.
Ustic moisture regime: Moisture control section is dry in some part more than about 90 days per year.
Udertic classification: Moisture control section is dry in some part from about 90 days to 135 days per year; cracks greater than 1 cm wide and 30 inches deep are present during dry periods.
ADDITIONAL DATA: Oklahoma State University laboratory data 76-OK-48-6 and State of Oklahoma, Department of Highways,
Materials Division laboratory data S68-OK-010-002.