LOCATION COYET              CO+UT WY
Established Series
DLS/GB
10/91

COYET SERIES


The Coyet series consists of very deep or deep, excessively drained soils formed in aeolian deposits, alluvium, and residuum derived from sandstone. Coyet soils are on hillslopes, breaks, alluvial fans, and plateaus. Slopes range from 3 to 50 percent. The mean annual precipitation is about 13 inches and the mean annual temperature is about 43 degrees F.

TAXONOMIC CLASS: Mixed, frigid Ustic Torripsamments

TYPICAL PEDON: Coyet loamy sand, rangeland. (Colors are for dry soil unless otherwise noted.)

A--0 to 6 inches; yellowish brown (10YR 5/4) loamy sand, brown (10YR 4/3) moist; weak medium granular structure parting to weak fine granular; soft, very friable, nonsticky and nonplastic; many fine and medium roots; mildly alkaline (pH 7.6); clear smooth boundary. (4 to 10 inches thick)

Bk1--6 to 22 inches; light yellowish brown (10YR 6/4) loamy sand, dark yellowish brown (10YR 4/4) moist; weak medium subangular blocky structure parting to weak fine subangular blocky; soft, very friable, nonsticky and nonplastic; common fine and medium roots; few fine filaments of calcium carbonate; strongly effervescent, mildly alkaline (pH 7.8); gradual wavy boundary. (0 to 20 inches thick)

Bk2--22 to 60 inches; very pale brown (10YR 7/3) loamy sand, yellowish brown (10YR 5/4) moist; massive; soft, very friable, nonsticky and nonplastic; common fine filaments and masses of calcium carbonate, strongly effervescent; moderately alkaline (pH 8.0).

TYPE LOCATION: Moffat County, Colorado; approximately 6 miles northeast of Maybell, about 1,300 feet north and 1,400 feet east of the southwest corner of Sec. 17, T. 7 N., R. 94 W. Longitude: 107 degrees, 58 minutes, 30 seconds west; latitude: 40 degrees, 33 minutes, 15 seconds north.

RANGE IN CHARACTERISTICS: Mean annual soil temperature ranges from 44 to 47 degrees F., and mean summer soil temperature ranges from 60 to 66 degrees F. The moisture control section is moist in all parts for 45 or more consecutive days immediately following April 1 and dry in all parts for 60 consecutive days immediately following July 1. Depth to lime carbonates ranges from 0 to 10 inches. The particle-size control section has 0 to 15 percent pebbles. A paralithic contact is at a depth of 40 to 60 inches in some pedons. In some pedons the Bk horizons are absent and C horizons are present.

The A horizon has hue of 2.5Y through 7.5YR, value of 4 or 5 dry, 3 or 4 moist, and chroma of 3 or 4. Reaction is mildly alkaline or moderately alkaline.

The Bk1 horizon has hue of 2.5Y through 7.5YR, value of 5 or 6 dry, 4 or 5 moist, and chroma of 3 or 4. It is loamy sand or loamy fine sand. Reaction is mildly alkaline or moderately alkaline. This horizon is absent in some pedons.

The Bk2 horizon has hue of 2.5Y through 7.5YR, value of 6 or 7 dry, 5 or 6 moist, and chroma of 3 or 4. It is loamy sand, loamy fine sand, or sand. Content of rock fragments ranges from 0 to 15 percent. Reaction is moderately alkaline or strongly alkaline. The C horizons, when present, have colors, textures, and reaction which are the same as the Bk horizons.

COMPETING SERIES: These are the Lamarsh (T) (WY), Maybell (T) (CO), Trey (SD), Tusler (ND), Yetull (MT), Zeomont (WY), and Zeona (SD) series. Lamarsh soils have a lithic contact at depths of 20 to 40 inches. Tusler and Trey soils have a paralithic contact at depths of 20 to 40 inches. Maybell, Zeomont, and Zeona soils are noncalcareous to depths of 40 or more inches. Yetull soils are moist in some part of the moisture control section for some period immediately after July 1.

GEOGRAPHIC SETTING: Coyet soils are on hillslopes, breaks, alluvial fans, and plateaus. Slopes range from 3 to 50 percent. The soil formed in aeolian deposits, alluvium, and residuum derived from sandstone. Elevation ranges from 5,800 to 7,200 feet. The average annual precipitation ranges from 10 to 14 inches. Average annual temperature

ranges from 42 to 45 degrees F. The frost-free period is about 60 to 95 days. June and July are the driest months during the growing season.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Crestman, Grieves, Maybell, Rock River, and Ryan Park soils. Crestman soils are shallow to bedrock. Grieves soils are in a coarse-loamy family. Maybell soils are noncalcareous to 40 inches or more. Rock River and Ryan Park soils have argillic horizons and are not in a sandy particle-size class.

DRAINAGE AND PERMEABILITY: Excessively drained; slow runoff; moderately rapid permeability.

USE AND VEGETATION: These soils are used for livestock grazing and wildlife habitat. Native vegetation consists of prairie junegrass, Indian ricegrass, needleandthread, sand dropseed, antelope bitterbrush, and silver sagebrush.

DISTRIBUTION AND EXTENT: These soils occur in northwestern Colorado. The series is of moderate extent. Total area is about 30,000 acres.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana

SERIES ESTABLISHED: Henry's Fork Soil Survey Area in Utah and Wyoming, 1990.

REMARKS: The diagnostic horizon recognized in this pedon is the ochric epipedon - the zone from 0 to 6 inches. Last updated by the state 12/90.


National Cooperative Soil Survey
U.S.A.