LOCATION SARCILLO COEstablished Series
TAXONOMIC CLASS: Clayey, smectitic, mesic Lithic Haplustalfs
TYPICAL PEDON: Sarcillo loam, on west convex slope of 3 percent under pinion, juniper and grassland. (Colors are for dry soil unless otherwise noted).
A--0 to 5 inches; brown (7.5YR 5/2) loam, brown (7.5YR 4/2) moist; weak fine granular structure; slightly hard, very friable, slightly sticky and nonplastic; neutral (pH 6.8); clear smooth boundary. (3 to 6 inches thick)
Bt--5 to 8 inches; light brown (7.5YR 6/4) clay loam, brown (7.5YR 4/4) moist; strong fine subangular blocky structure; hard, firm, sticky and plastic; common continuous clay films on ped faces; slightly alkaline (pH 7.4); abrupt smooth boundary. (2 to 4 inches thick)
Btss1--8 to 13 inches; light brown (7.5YR 6/4) clay, brown (7.5YR 5/4) moist; strong medium prismatic structure parting to moderate medium angular blocks; extremely hard, very firm, sticky and plastic; many continuous clay films on peds faces; many slickensides; slightly alkaline (pH 7.4); abrupt boundary. (4 to 7 inches thick)
Btss2--13 to 16 inches; pale brown (10YR 6/3) clay, brown (10YR 5/3) moist; strong medium angular blocky structure; extremely hard, very firm, sticky and plastic; common continuous clay films on ped faces; few slickensides; slightly effervescent; slightly alkaline (pH 7.8); abrupt smooth boundary. (1 to 3 inches thick)
R--16 inches; indurated sandstone.
TYPE LOCATION: Las Animas, Colorado, about 9 miles west of Trinidad and 1.5 miles north of Hwy. 12 off Burro Canyon road; 1,100 feet south and 2,500 feet west of the northeast corner of Sec. 27, T. 33 S., R. 65 W.; Madrid USGS quad; Latitude 37 degrees, 8 minutes, 48 seconds N., longitude 104 degrees, 39 minutes, 26 seconds West.
RANGE IN CHARACTERISTICS:
Soil moisture: moist intermittently April through August, dry December through February. Ustic moisture regime bordering on aridic.
Mean annual soil temperature ranges from 48 to 54 degrees.
Mean summer soil temperature: 64 to 68 degrees f.
Thickness of the solum and depth to lithic contact: 10 to 20 inches.
Depth to uniformly calcareous material: 10 to 20 inches.
A thin C horizon may be present in some pedons.
Particle size control section: (weighted average)
Clay content: 35 to 45 percent
Rock fragment content: 0 to 20 percent, mainly gravel and cobbles
A horizon:
Hue: 10YR or 7.5YR
Value: 4 through 6 dry, 3 or 4 moist
Chroma: 2 through 4
Clay content: 15 to 30 percent
Reaction: slightly acid or neutral.
Bt horizon:
Hue: 2.5Y through 7.5YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 3 through 6
Clay content: 35 to 45 percent
Texture: clay, silty clay, or clay loam
Reaction: neutral to moderately alkaline.
Btss horizon:
Hue: 2.5Y through 7.5YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 3 through 6
Clay content: 40 to 50 percent
Texture: clay, silty clay, or clay loam
Reaction: neutral to moderately alkaline
Slickensides are few to many.
COMPETING SERIES: These are the
Toqui (AZ) series.
Toqui soils: have hues of 5YR or redder in the Bt horizon, have dry soil moisture control sections in
May and June, and have calcium carbonate equivalent of 15 to 45 percent in the Bk horizon.
GEOGRAPHIC SETTING:
Parent material: slope alluvium derived from stratified sandstone and shale, commonly the Raton Formation.
Landform: ridges and hills.
Elevation: 6,500 to 7,800 feet.
Slopes: 2 to 15 percent, but range to 40 percent.
Mean annual precipitation: 15 to 18 inches.
Mean annual air temperature is 48 to 52 degrees F.
Frost-free period is 100 to 125 days
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Lorencito and
Trujillo soils.
Lorencito soils: have a paralithic contact and are on steep backslopes of hills.
Trujillo soils: are very deep, have a mollic epipedon, and are on footslopes and toeslopes of hills.
DRAINAGE AND PERMEABILITY: Well drained; rapid runoff; slow permeability.
USE AND VEGETATION: These soils are used principally as rangeland and wildlife habitat. Principal native vegetation consists of bluestems, blue grama, mountain mahogany, sideoats grama, needleandthread, Gambels oak, pinyon and juniper.
DISTRIBUTION AND EXTENT: Southeastern Colorado foothills. LRR E, MLRA 49. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Las Animas County, Colorado, 2007. The name is from a major drainage area in the foothills of Las Animas County.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: the zone from 0 to 5 inches. (A horizon)
Argillic horizon: the zone from 5 to 16 inches. (Bt, Btss1, and Btss2 horizons)
Lithic contact: hard sandstone at 16 inches. (R horizon)
Other features: slickensides in the zone from 8 to 16 inches. (Btss1 and Btss2 horizons)
Taxonomic Version: Tenth Edition, 2006.