LOCATION EASPUR OKEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, thermic Fluventic Haplustolls
TYPICAL PEDON: Easpur loam--cultivated. (Colors are for dry soil unless otherwise stated.)
Ap--0 to 11 inches; reddish brown (5YR 4/3) loam, dark reddish brown (5YR 3/3) moist; weak fine granular structure; slightly hard, friable; many fine roots; slightly acid; clear smooth boundary. (8 to 14 inches thick)
Bw1--11 to 19 inches; reddish brown (5YR 5/4) fine sandy loam, reddish brown (5YR 4/4) moist; weak fine granular structure; soft, very friable; many fine roots; neutral; clear smooth boundary. (6 to 24 inches thick)
Bw2--19 to 29 inches; reddish brown (5YR 4/4) clay loam, dark reddish brown (5YR 3/4) moist; moderate fine granular structure; hard, firm; few fine roots; neutral; clear smooth boundary. (0 to 24 inches thick).
C--29 to 41 inches; stratified reddish brown (5YR 5/4) loam, yellowish red (5YR 5/6) fine sandy loam and reddish brown (5YR 4/3) clay loam; massive; slightly hard, friable; few fine roots; strata are 1 to 4 inches thick; slightly alkaline; clear smooth boundary. (0 to 33 inches thick)
2Ab--41 to 62 inches; dark reddish gray (5YR 4/2) silty clay loam, dark reddish brown (5YR 3/2) moist; moderate fine granular structure; hard, firm; slightly alkaline; clear smooth boundary. (10 to 21 inches thick)
2Bwb--62 to 72 inches; reddish brown (5YR 4/4) silty clay loam, dark reddish brown (5YR 3/4) moist; weak medium subangular blocky structure; hard, firm; slightly alkaline.
TYPE LOCATION: Payne County, Oklahoma; about 1/2 mile west of Stillwater, Oklahoma; 2,000 feet east and 1,300 feet north of the southwest corner of sec. 16, T. 19 N., R. 2 E.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 20 to more than 60 inches and commonly is the same as depth to buried horizons. Secondary carbonates are present in some pedons, but are below 50 inches.
The Ap or A horizon has hue of 5YR or 7.5YR, value of 4 or 5, and chroma of 2 or 3. Texture is loam or silt loam. Reaction ranges from moderately acid to moderately alkaline.
The Bw horizon has hue of 2.5YR to 7.5YR, value of 4 to 6, and chroma of 3 to 6. Texture is loam, clay loam, fine sandy loam, or very fine sandy loam. Reaction ranges from slightly acid to moderately alkaline.
The C horizon has hue of 2.5YR to 10YR, value of 4 to 7, and chroma of 3 to 6. It is stratified with thin layers of fine sandy loam to clay loam. Reaction ranges from slightly acid to moderately alkaline.
The 2Ab horizon has hue of 5YR or 7.5YR, value of 3 to 5, and chroma of 2 or 3. Texture is silt loam, silty clay loam, clay loam, or loam. Reaction ranges from slightly acid to moderately alkaline.
The 2Bwb horizon has hue of 5YR to 10YR, value of 4 or 5, and chroma of 2 to 4. Texture is silt loam, silty clay loam, clay loam, or loam. Reaction ranges from slightly acid to moderately alkaline.
COMPETING SERIES: These are the Pursley and Spur series in the same family. Soils in similar families are Asher, Bippus, Bosque, Bunyan, Gageby, Gowen, Kaski, Lamkin, Pocasset, Whitesboro, and Zenda series. Asher and Lamkin soils have a fine-silty control section. Bippus, Bosque, Gageby, Gowen, Kaski and Whitesboro soils have a mollic epipedon more than 20 inches thick. Bunyan soils lack a mollic epipedon. Pocasset soils have a coarse-loamy control section. Pursley soils have subsoils with hue of 10YR or yellower. Spur soils are dry for longer periods and are calcareous within 40 inches. Zenda soils have an apparent water table between 2 and 4 feet.
GEOGRAPHIC SETTING: Easpur soils are on nearly level flood plains of small streams in the Central Rolling Red Prairies. Slopes are 0 to 1 percent. These soils formed in loamy alluvium of Recent age. Mean Annual Precipitation: 26 to 38 inches. Mean Annual Temperature: 58 to 63 degrees F. Thornthwaite Annual P-E indices: 44 to 64. Frost free days range from 200 to 230. Elevation ranges from 700 to 1500 feet.
GEOGRAPHICALLY ASSOCIATED SOILS: These include the Port, Dale, and Pulaski series. Port soils are on similar landscapes as the Easpur soils, but Port soils have a mollic epipedon more than 20 inches thick and have a fine-silty control section. Dale soils are on slightly higher landscapes and are rarely flooded. In addition, Dale soils have a mollic epipedon more than 20 inches thick and have a fine-silty control section. Pulaski soils are typically closer to the stream channel, have a coarse-loamy control section, and lack a mollic epipedon.
DRAINAGE AND PERMEABILITY: Easpur soils are well drained. Runoff is negligible and permeability is moderate. These soils are occasionally flooded for very brief to brief periods during March to October.
USE AND VEGETATION: These soils are mainly cultivated. Alfalfa, small grains, and grain sorghum are the principal crops. Some areas are used for improved pasture or rangeland. Native vegetation is tall grasses with an overstory of pecan, black walnut, bur oak, and Eastern cottonwood trees.
DISTRIBUTION AND EXTENT: Central Rolling Red Prairies (MLRA 80A) of Oklahoma. The soil is of small extent.
MLRA OFFICE RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Payne County, Oklahoma; 1983.
REMARKS: These soils were formerly included in the Port series in earlier surveys.
Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - the zone from the surface of the soil to a depth of 11 inches (A horizon).
Cambic horizon - the zone from 11 inches to a depth of 19 inches (Bw horizon).
Lithologic discontinuity - the contrasting material at a depth of 41 inches.
ADDITIONAL DATA: Sample 79-OK-60-16 was done by Oklahoma State University.