LOCATION BELMEAR COTentative Series
TAXONOMIC CLASS: Fine, smectitic, frigid Aridic Haplusterts
TYPICAL PEDON: Belmear silty clay, grassland. (Colors are for dry soil unless otherwise noted.)
A1--0 to 10 inches, grayish brown (10YR 5/2) silty clay, very dark grayish brown (10YR 3/2) moist; strong fine granular structure; soft, very friable, slightly sticky and slightly plastic; calcareous; moderately alkaline; clear smooth boundary. (6 to 15 inches thick)
C1--10 to 30 inches; grayish brown (2.5Y 5/2) silty clay, dark grayish brown (2.5Y 4/2) moist; massive; extremely hard, firm, sticky and plastic; few small shiny slickenside surfaces; calcareous; moderately alkaline; gradual wavy boundary. (5 to 34 inches thick)
C2r--30 to 40 inches, calcareous clay shale.
TYPE LOCATION: Montezuma County, Colorado; along the west side of the NW 1/4 of Sec. 2, T. 36 N., R. 14 W.
RANGE IN CHARACTERISTICS: Depth to uniformly calcareous material ranges from 0 to 6 inches, but does not exceed one-half the thickness of the mollic epipedon. Depth to the paralithic contact ranges from 20 to 40 inches. Continuous horizons of calcium carbonate do not occur with the control section although some visible accumulation may occur at any depth. Rock fragments range from 0 to about 5 percent.
The A horizon has hue of 5Y through 7.5YR, value of 4.5 through 5.5 dry, 2 or 3 moist, and chroma of 1 through 3. It is mildly alkaline or moderately alkaline.
The C horizon has hue of 5Y through 7.5YR. It is normally heavy silty clay loam or silty clay but clay ranges from 35 to 50 percent, silt from 25 to 60 percent, and sand from 5 to 35 percent. This horizon is moderately alkaline or strongly alkaline.
COMPETING SERIES: These are the Kildore and Shrine series. Kildore soils have a cryic temperature regime, a cambic horizon, and have continuous genetic horizons of carbonate accumulation. Shrine soils have a fine-loamy control section and have no bedrock above depth of 40 inches.
GEOGRAPHIC SETTING: The Belmear soils are on gently to steep sloping ridges and hillsides. Slopes range from about 2 to 45 percent. The soil formed in moderately thin, calcareous, fine textured material weathered residually or locally transported from clay shale. At the type location the mean annual precipitation is about 16 inches. Mean annual temperature is 42 degrees F., mean summer temperature is 61 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Midway and Hesperus soils. Midway soils are less than 20 inches deep over shale. Hesperus soils are coarser textured, noncalcareous, and have thick mollic epipedons of low chroma.
DRAINAGE AND PERMEABILITY: Well drained; medium to rapid runoff, moderately slow to slow permeability.
USE AND VEGETATION: These soils are used principally as native grazing lands. Native vegetation is mainly pinon, juniper and ponderosa pine, with an understory of western wheatgrass and Indian ricegrass.
DISTRIBUTION AND EXTENT: Southwestern Colorado. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES PROPOSED: Cortez Area, Colorado, 1972.
REMARKS: Last updated by the state 4/76.