LOCATION LESWILL COEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, frigid Typic Haplogypsids
TYPICAL PEDON: Leswill clay loam - rangeland. (Colors are for dry soil unless otherwise indicated).
A1--0 to 2 inches; light brownish gray (2.5Y 6/2) clay loam, grayish brown (2.5Y 5/2) moist; weak medium granular structure parting to moderate fine granular; soft, very friable, slightly sticky and plastic; strongly effervescent, mildly alkaline (pH 7.8); abrupt smooth boundary. (1 to 4 inches thick)
A2--2 to 5 inches; light brownish gray (2.5Y 6/2) clay loam, grayish brown (2.5Y 5/2) moist; weak thick platy structure parting to weak fine subangular blocky; slightly hard, friable, slightly sticky and slightly plastic; strongly effervescent; strongly alkaline (pH 8.5); abrupt smooth boundary. (0 to 5 inches thick)
Bw--5 to 14 inches; light brownish gray (2.5Y 6/2) clay loam, grayish brown (2.5Y 5/2) moist; weak medium subangular blocky structure; hard, friable, sticky and plastic; strongly effervescent; strongly alkaline (pH 8.6); clear wavy boundary. (0 to 12 inches thick)
By1--14 to 20 inches; light yellowish brown (2.5Y 6/4) silty clay loam, grayish brown (2.5Y 5/2) moist; weak medium subangular blocky structure; slightly hard, friable, sticky and plastic; 4 percent calcium sulfate; slightly effervescent; moderately alkaline (ph 7.9); clear wavy boundary. (6 to 10 inches thick)
By2--20 to 30 inches; light yellowish brown (2.5Y 6/4) silty clay loam, light olive brown (2.5Y 5/4) moist; weak medium subangular blocky structure; slightly hard, friable, sticky and plastic; 10 percent calcium sulfate; slightly effervescent; moderately alkaline (pH 8.0); clear wavy boundary. (6 to 12 inches thick)
By3--30 to 41 inches; light yellowish brown (2.5Y 6/4) clay loam, light olive brown (2.5Y 5/4) moist; massive; hard, firm, sticky and plastic; 15 percent calcium sulfate; strongly effervescent; moderately alkaline (pH 8.3); clear wavy boundary. (6 to 15 inches thick)
C1--41 to 52 inches; light yellowish brown (2.5Y 6/4) clay loam, olive brown (2.5Y 4/3) moist; massive; hard, firm, sticky and plastic; 3 percent calcium sulfate; strongly effervescent; moderately alkaline (pH 8.3); clear wavy boundary. (0 to 12 inches thick)
C2--52 to 75 inches; light brownish gray (2.5Y 6.2) silty clay loam, grayish brown (2.5Y 5/2) moist; massive; hard, firm, slightly sticky and slightly plastic; 7 percent calcium sulfate; strongly effervescent; moderately alkaline (pH 8.1).
TYPE LOCATION: Moffat County, Colorado; 7 miles south of Hiawatha, 1,000 feet south and 250 feet east of the northwest corner of Sec. 28, T. 11 N., R. 100 W. Latitude 40 degrees, 53 minutes, 19 seconds north. Longitude 108 degrees, 38 minutes, 49 seconds west.
RANGE IN CHARACTERISTICS: Mean annual soil temperature ranges from 42 to 46 degrees F. The product of the percentage of gypsum and the thickness in centimeters above a depth of 60 inches is less than 3,000. Clay content in the particle-size control section is 27 to 35 percent, and the percent fine and coarser sand is less than 15 percent in the particle-size control section. The gypsic horizon is at a depth of 10 to 40 inches and it contains 10 to 25 percent calcium sulfate. The total of calcium sulfate plus calcium carbonate equivalent averages 20 to 39 percent by weight in the control section.
The A horizon has hue of 5Y through 10YR, value of 5 through 7, 4 through 6 moist, and chroma of 2 through 4. Reaction is mildly alkaline to strongly alkaline.
The B horizon, if present, has hue of 5Y through 10YR, value of 4 through 7, 4 through 6 moist, and chroma of 2 through 6. Reaction is moderately alkaline or strongly alkaline. Textures range from clay loam or silty clay loam.
The C horizon has hue of 5Y through 10YR, value of 5 through 7, 4 through 6 moist, and chroma of 2 through 6. Reaction is moderately alkaline or strongly alkaline. Textures are clay loam or silty clay loam.
COMPETING SERIES: There are no known competing soils in this family. The Deseret and Tohona series have mesic temperatures.
GEOGRAPHIC SETTING: Leswill soils are on dissected plateaus and side slopes at elevations of 6,000 to 7,200 feet. Slopes are 0 to 7 percent. These soils formed in residuum from gypsiferous shales. Mean annual precipitation is 7 to 11 inches, and the mean annual temperature is 41 to 45 degrees F. The frost-free period is 75 to 95 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Rogrube and Talamantes series. Rogrube soils lack a gypsic bulge and have fine-loamy particle-size control sections. Talamantes soils lack a gypsic horizon and a cambic horizon and have fine-loamy particle-size control sections.
DRAINAGE AND PERMEABILITY: Well drained; moderate runoff; moderately slow permeability.
USE AND VEGETATION: These soils are used primarily for livestock grazing. Principal native vegetation is gardner saltbrush and Rumex.
DISTRIBUTION AND EXTENT: Northwest Colorado. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Moffat County (Moffat County Area), Colorado, 1991.
REMARKS: The name is coined. Diagnostic features recognized in this pedon are: a gypsic horizon between depths of 20 to 41 inches. Last updated by the state 12/90.