LOCATION DOOLIN OKEstablished Series
TAXONOMIC CLASS: Fine, smectitic, thermic Typic Natrustolls
TYPICAL PEDON: Doolin silt loam--on a 0.5 percent slope--rangeland. (Colors are for dry soil unless otherwise stated.)
A--0 to 12 inches; grayish brown (10YR 5/2) silt loam, very dark grayish brown (10YR 3/2) moist; moderate medium granular structure; slightly hard, friable; slightly acid; abrupt smooth boundary. (10 to 15 inches thick)
Btn1--12 to 20 inches; dark brown (7.5YR 4/2) silty clay loam, dark brown (7.5YR 3/2) moist; common fine distinct reddish brown mottles; strong coarse columnar structure parting to moderate medium blocky; hard, firm; thick nearly continuous clay films on faces of peds; few fine dark brown concretions; organic matter staining on faces of peds; exchangeable sodium percentage is 16; neutral; clear smooth boundary. (6 to 14 inches thick)
Btn2--20 to 32 inches; dark brown (10YR 4/3) silty clay loam, dark brown (10YR 3/3) moist; few fine distinct strong brown mottles; moderate medium blocky structure; hard, firm; thin nearly continuous clay films on the faces of peds; organic matter staining between faces of peds; exchangeable sodium percentage is 15; slightly alkaline; gradual smooth boundary. (0 to 21 inches thick)
2Btn3--32 to 48 inches; brown (7.5YR 5/4) clay loam, brown (7.5YR 4/4) moist; many medium prominent strong brown (7.5YR 5/6) and dark yellowish brown (10YR 4/4) mottles; weak coarse prismatic structure; hard, firm; thin patchy clay films on faces of peds; many threads of salts; exchangeable sodium percentage is 18; few medium and fine calcium carbonate concretions; slightly alkaline; gradual smooth boundary. (9 to 30 inches thick)
2Btn4--48 to 68 inches; reddish yellow (7.5YR 6/8) clay loam, strong brown (7.5YR 5/8) moist; many coarse prominent gray (10YR 5/1), light gray (10YR 7/2), and red (2.5YR 4/8) mottles; weak coarse prismatic structure; hard, firm; thin patchy clay films on faces of peds; exchangeable sodium percentage is 18; slightly alkaline; abrupt smooth boundary. (0 to 35 inches thick)
2Cr--68 to 70 inches; strong brown (7.5YR 5/6) sandstone.
TYPE LOCATION: Payne County, Oklahoma; about 10 miles east and 3 miles north of Stillwater; 1,100 feet west and 50 feet south of the northeast corner of sec. 2, T. 19 N., R. 4 E.
RANGE IN CHARACTERISTICS: Depth to secondary carbonates is more than 30 inches. Solum thickness is more than 60 inches and commonly is the same as the depth to bedrock. The exchangeable sodium percentage ranges from 15 to 20 percent in the Btn and 2Btn horizons. The electrical conductivity of saturation extract ranges from 0 to 2 millimhos/cm in the A and Btn horizons and ranges from 2 to 6 millimhos/cm in the 2Btn horizons.
The Ap or A horizon has hue of 7.5YR or 10YR, value of 4 or 5, and chroma of 2. Texture is silt loam, loam, or very fine sandy loam. Reaction ranges from moderately acid to slightly alkaline.
The Btn1 horizon has hue of 7.5YR or 10YR, value of 4 or 5, and chroma of 2 to 6. Some pedons have ped faces with a value and chroma lower than the matrix. Texture is silty clay loam, silty clay, or clay. Rounded dark concretions make up 0 to 5 percent by volume. Reaction ranges from slightly acid to moderately alkaline.
The Btn2 horizon has hue 7.5YR or 10YR, value of 4 to 6, and chroma of 2 to 6. Mottles are in shades of brown. Texture is silty clay loam, clay, silty clay, or clay loam. Reaction is slightly to moderately alkaline.
The 2Btn3 and 2Btn4 horizons have hue of 2.5YR to 7.5YR, value of 4 to 6, and chroma of 3 to 8. Mottles are in shades of red, brown, and gray in the lower part. Texture is clay loam or sandy clay loam. Calcium carbonate concretions are present in the upper part of most pedons. Threads of salts are present in most pedons. Reaction is slightly or moderately alkaline.
The 2Cr horizon consists of red or brown sandstone.
COMPETING SERIES: There are no other series in the same family. Soils in similar families are the Drummond, Foard, Hinkle, Kirkland, Pawhuska, Renfrow, Seminole, Waurika, and Wing soils. Drummond, Pawhuska, and Seminole soils have mixed mineralogy. In addition, Seminole soils lack an abrupt textural change between the A and Btn horizons. Drummond, Hinkle, and Pawhuska soils lack mollic epipedons. In addition, Drummond soils have a solum less than 60 inches thick. Foard soils are dry for longer periods and have secondary carbonates between 12 and 30 inches of the surface. Kirkland, Renfrow, and Waurika soils lack a natric horizon. Wing soils have wetness mottles within 20 inches of the surface.
GEOGRAPHIC SETTING: Doolin soils are on broad, slightly concave, nearly level to very gently sloping summits or divides and interfluves on uplands in the Central Rolling Red Prairies. Slopes range from 0 to 3 percent. The upper part of the soil formed in old alluvium and the lower part formed in sandstone of Permian age. Mean Annual Precipitation: 26 to 40 inches. Mean Annual Temperature: 58 to 64 degrees F. Thornthwaite Annual P-E indices: 44 to 64.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the similar Kirkland, Pawhuska and Renfrow series and the Chickasha and Zaneis series. Chickasha and Zaneis soils lack a natric horizon, have a fine-loamy control section, and occur on side slopes below the Doolin soils. Kirkland and Pawhuska soils are on similar landscapes. Renfrow soils are commonly on upper side slopes below the Doolin soils.
DRAINAGE AND PERMEABILITY: Moderately well drained; very slowly permeable. Runoff is negligible on concave areas, high on 0 to 1 percent slopes and very high on 1 to 3 percent slopes. Wetness characteristics do not reflect current redoxomorphic features, but are relict.
USE AND VEGETATION: Most areas have been cultivated and are now in low condition grasses such as threeawn. These areas are used for rangeland. Some areas are cultivated to small grains or improved pasture. Native vegetation is mainly mid and short grass prairie.
DISTRIBUTION AND EXTENT: Central Rolling Red Prairies (MLRA 80A) of Oklahoma. The series is not extensive.
MLRA OFFICE RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Payne County, Oklahoma; 1983.
REMARKS: These soils were formerly included in the Kirkland series.
Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - the zone from the surface of the soil to a depth of 32 inches (A and Btn horizons).
Argillic horizon - the zone from 12 inches to a depth of 68 inches (Bt horizons).
Natric horizon - the zone from 12 inches to a depth of 68 inches (Btn horizons).
Lithologic discontinuity - contrasting material at a depth of 32 inches.
ADDITIONAL DATA: Sample No. 79-OK-60-5 by Oklahoma State University.