LOCATION SAPEHA COEstablished Series
TAXONOMIC CLASS: Clayey-skeletal, smectitic, frigid Typic Haplustolls
TYPICAL PEDON: Sapeha very cobbly loam - native rangeland. (Colors are for dry soil unless otherwise noted.)
A1--0 to 5 inches; gray (10YR 5/1) very cobbly loam, black (10YR
2/1) moist; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; 15 percent pebbles, 35 percent cobbles, and 10 percent stones; neutral (pH 7.0); clear smooth boundary. (4 to 14 inches thick)
A2--5 to 12 inches; gray (10YR 5/1) cobbly clay loam, very dark grayish brown (10YR 3/2) moist; moderate medium subangular blocky structure; very hard, firm, slightly sticky and plastic; 10 percent pebbles, 15 percent cobbles, and 5 percent stones; neutral (pH 7.0); clear smooth boundary. (0 to 8 inches thick)
Bw--12 to 32 inches; yellowish brown (10YR 5/4) very cobbly clay, dark yellowish brown (10YR 4/4) moist; moderate medium subangular blocky structure; very hard, firm, slightly sticky and plastic; 15 percent pebbles, 35 percent cobbles, and 10 percent stones; neutral (pH 7.0); gradual smooth boundary. (10 to 25 inches thick)
C--32 to 60 inches; brown (10YR 5/3) extremely cobbly clay, dark brown (10YR 4/3) moist; massive; very hard, friable, slightly sticky and plastic; 15 percent pebbles, 35 percent cobbles, and 15 percent stones; neutral (pH 7.2).
TYPE LOCATION: San Miguel County, Colorado; 2,350 feet north and 500 feet west of the southwest corner of Sec. 15, T. 43 N., R. 14 W.
RANGE IN CHARACTERISTICS: Mean annual soil temperature ranges from 44 to 46 degrees F., and the mean summer soil temperature ranges from 60 to 64 degrees F. Rock fragments range from 35 to 65 percent. Cobbles are the dominant coarse fragment and pebbles and stones make up about 40 percent.
The A horizon has hue of 10YR or 7.5YR, value of 4 or 5 dry, and 2 or 3 moist, with chroma of 1 or 2.
The Bw horizon has hue of 10YR or 7.5YR, value of 5 or 6 dry, 4 or 5 moist, and chroma of 3 or 4. Textures are gravelly, cobbly, very cobbly, or extremely cobbly clay loam.
The C horizon has hue of 10YR or 7.5YR, value of 4 through 6 dry, and 4 or 5 moist, with chroma of 3 or 4. Textures are very cobbly clay loam or very stony or extremely cobbly clay.
COMPETING SERIES: There are currently no other series in this family.
GEOGRAPHIC SETTING: Sapeha soils are on mesa hillslopes. Slopes range from 15 to 50 percent. This soil formed in colluvium and alluvium derived from mixed igneous sources. Elevation ranges from 7,600 to 8,900 feet. The mean annual precipitation ranges from 16 to 18 inches. Mean annual temperature ranges from 41 to 44 degrees F. The frost-free period is 75 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Barkelew, Dapoin, Emmons, Leaps, Lillylands, Narraquinnep, and Ryman soils. Barkelew soils lack a mollic epipedon. Dapoin soils are not skeletal. Lillylands, Narraquinnep, and Ryman soils have a pachic epipedon. Emmons soils have a calcic horizon and are not skeletal. Leaps soils have a cryic temperature regime.
DRAINAGE AND PERMEABILITY: Well drained; very rapid runoff; moderately slow permeability.
USE AND VEGETATION: This soil is used for late spring, summer, and fall livestock grazing, recreation, and wildlife habitat. Principal native vegetation is Gambel oak, snowberry, Rocky Mountain juniper, yarrow, elk sedge, western wheatgrass, and Kentucky bluegrass.
DISTRIBUTION AND EXTENT: Southwestern Colorado and possibly adjacent parts of New Mexico and Utah. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: San Miguel County (San Miguel Area), Colorado, 1987.