LOCATION FORAKER OKEstablished Series
TAXONOMIC CLASS: Fine, smectitic, thermic Udertic Argiustolls
TYPICAL PEDON: Foraker silty clay loam - rangeland. (Colors are for dry soil unless otherwise stated.)
A--0 to 8 inches; very dark gray (10YR 3/1) channery silty clay loam, black (10YR 2/1) moist; strong medium granular structure; hard, friable; about 10 percent by volume of flat limestone fragments 2 mm. to 75 mm. in length and about 8 percent by volume of flat limestone fragments greater than 75 mm. in length; calcareous, moderately alkaline; clear smooth boundary. (4 to 9 inches thick)
BA--8 to 11 inches; dark gray (10YR 4/1) channery silty clay loam, very dark gray (10YR 3/1) moist; weak medium blocky structure parting to moderate medium granular structure; very hard, very firm; about 15 percent by volume of flat limestone fragments 2 mm. to 75 mm. in length; calcareous, moderately alkaline; clear smooth boundary. (0 to 6 inches thick)
Btk--11 to 26 inches; gray (5Y 5/1) silty clay, dark gray (5Y 4/1) moist; few fine distinct yellowish brown redox iron concentrations; moderate medium blocky structure; very hard, very firm; nearly continuous clay films on faces of peds; few non-intersecting slickensides; 5 percent calcium carbonate concretions; about 2 percent by volume of shale fragments 2 mm. to 75 mm. in length; calcareous, moderately alkaline; gradual wavy boundary. (5 to 15 inches thick)
BCk--26 to 38 inches; light olive gray (5Y 6/2) silty clay with soft shale fragments, olive gray (5Y 5/2) moist; common fine and medium distinct yellowish brown (10YR 5/8) redox iron concentrations; weak medium blocky structure; very hard, very firm; nearly continuous clay films on faces of peds; about 30 percent by volume of shale fragments 2 mm. to 75 mm. in length; 5 percent by volume of calcium carbonate concretions; calcareous, moderately alkaline; gradual wavy boundary. (5 to 30 inches thick)
Cr--38 to 48 inches; olive gray (5Y 5/2), gray (5Y 5/1), and yellowish brown (10YR 5/8) soft laminated shale; calcareous, moderately alkaline.
TYPE LOCATION: Osage County, Oklahoma; about 8 miles north and 1 mile east of Foraker; 2,200 feet west and 1,000 feet south of the northeast corner of sec. 16, T. 29 N., R. 7 E.
RANGE IN CHARACTERISTICS: Solum thickness and depth to shale bedrock range from 20 to 40 inches. Stony phases are recognized. This soil has cracks during summer months in most years, one-half inch or more wide and at least 20 inches in length at a depth of 20 inches, has a linear extensibility of more than 2.5 inches and a COLE of 0.07 or more in some horizon. It is calcareous and moderately alkaline in all horizons. The low chroma colors are dominantly inherited from the parent material.
The A horizon has hue of 10YR or 2.5Y, value of 3 to 5, chroma of 1 or 2. It is silty clay loam and contains flat limestone fragments greater than 75 mm. in length that range from 0 to 50 percent by volume and flat limestone fragments from 2 mm. to 75 mm. in length that range from 0 to 30 percent by volume.
The BA horizon has hue of 10YR or 2.5Y, value of 4 or 5, and chroma of 1 or 2. It is silty clay loam and contains flat limestone fragments greater than 75 mm. in length that range from 5 to 20 percent by volume and flat limestone fragments from 2 mm. to 75 mm. in length that range from 0 to 25 percent by volume.
The Btk horizon has hue of 10YR or 2.5Y, value of 4 to 6, and chroma of 1 to 4 or hue of 5Y, value of 5 and chroma of 1. Some pedons have grayish, brownish, yellowish, or reddish redox depletions or iron concentrations. This horizon is silty clay loam or silty clay. The clay content of the control section ranges from 35 to 55 percent, averaging about 40 percent. Fragments of shale and calcium carbonate concretions from 2 mm. to 75 mm. in diameter range from 0 to 15 percent by volume.
The BCk horizon has hue of 2.5Y or 5Y, value of 5 or 6, and chroma of 2 to 4. Some pedons have grayish, brownish, or yellowish mottles. This horizon is silty clay loam or silty clay. Shale fragments and calcium carbonate concretions from 2 mm. to 75 mm. in diameter range from 5 to 75 percent by volume.
The Cr horizon is dominantly coarsely mottled in shades of gray, brown, or olive; which colors are inherited from the shale parent material. It is mainly laminated silty shale interbedded with limestone, but some areas are compact silty clay. Some pedons have films of calcium carbonate in between the rock structure of the shale.
COMPETING SERIES: These are the Benchley, Caradan, Durant, Flatonia, and Tabler series. Benchley, Caradan, Durant, Flatonia, and Tabler soils all have a solum more than 40 inches thick. In addition, Benchley, Caradan, and Flatonia soils have mean annual temperature over 64 degrees F.
GEOGRAPHIC SETTING: The Foraker soils occur on convex moderately steep or steep slopes of prairie uplands. Slopes range from 3 to 25 percent. These soils have formed in material weathered from alkaline shales interbedded with thin layers of limestone of Pennsylvanian age. The climate is moist subhumid. Thornthwaite annual P-E index ranges from 54 to 64; average annual precipitation ranges from 31 to 38 inches; and the annual mean temperature ranges from 58 degrees to 63 degrees F. Frost free days range from 200 to 220 days. Elevation ranges from 700 to 1200 feet.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Grainola series on similar landscapes, and the Apperson and Shidler series. Apperson soils are on broad, smooth ridges and gently sloping side slopes and have a solum 40 to 60 inches thick over hard limestone. Shidler soils are on higher landscapes, do not have a Bt horizon, have a fine-silty control section, and are less than 20 inches to hard limestone.
DRAINAGE AND PERMEABILITY: Moderately well drained; medium to rapid runoff; slow permeability. A perched water table ranges from near the surface to 2.0 feet sometime during the period of November through April in most years.
USE AND VEGETATION: Nearly all used for native range. The native vegetation is tall grass prairie.
DISTRIBUTION AND EXTENT: North central Oklahoma and possibly south central Kansas. The series is moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Osage County, Oklahoma; 1975.
REMARKS: The Foraker soils were formerly included in the Clime series. Diagnostic horizons and features in this pedon are:
Mollic epipedon 0 to 11 inches.
Argillic horizon 11 to 38 inches.
Paralithic contact at 38 inches.
Ustic moisture regime: Moisture control section is dry in some part more than 90 days per year.
Udertic: Moisture control section is dry in some part from 90 to 135 days per year; cracks greater than 1 cm wide and 30 inches deep are present during dry periods.
ADDITIONAL DATA: Laboratory data for this pedon was done by O.S.U., Sample 73-OK-57-22(1-5).
Soil Interpretation Record: Foraker Series OK0171