LOCATION DEVOE WYEstablished Series
TAXONOMIC CLASS: Loamy, mixed, superactive, shallow Ustic Haplocryolls
TYPICAL PEDON: Devoe gravelly loam, grassland. (Colors are for air dry soil unless otherwise noted.)
A--0 to 9 inches; brown (7.5YR 5/3) gravelly loam, dark brown (7.5YR 3/3) moist; strong fine crumb structure; soft, very friable, moderately sticky and slightly plastic; 20 percent gravel and cobbles, mainly concentrated at the surface; calcareous; moderately alkaline (pH 8.0); gradual smooth boundary. (7 to 10 inches thick)
Bw--9 to 15 inches; light reddish brown (5YR 6/4) gravelly loam, reddish brown (5YR 4/4) moist; weak prismatic structure that parts to fine subangular blocks; slightly hard, very friable, moderately sticky and slightly plastic; 15 percent gravel, mostly limestone; calcareous; moderately alkaline (pH 8.2); gradual wavy boundary. (4 to 10 inches thick)
Cr--15 to 20 inches; reddish brown calcareous shale with thin discontinuous lenses of limestone.
TYPE LOCATION: Johnson County, Wyoming; NW1/4 SW1/4 sec. 26, T.45N., R.84W.
RANGE IN CHARACTERISTICS: The mollic epipedon ranges from 7 to 15 inches thick. Depth to calcareous material ranges from 0 to 4 inches, thickness of the solum ranges from 10 to 20 inches and depth to the paralithic contact ranges from 10 to 20 inches. Organic carbon ranges from .7 to 1.5 percent in the surface horizons and decreases uniformly as depth increases. Gravel is 15 to 35 percent and cobbles are 0 to 5 percent. The control section is typically gravelly loam or clay loam, but matrix material ranges in clay from 18 to 35 percent, silt from 20 to 50 percent, and sand from 20 to 50 percent with less than 35 percent fine sand or coarser. The mean annual soil temperature ranges from 32 degrees to 47 degrees F. and the mean summer soil temperature ranges from 40 degrees to 58 degrees F. without an O horizon.
The A horizon has hue of 7.5YR through 2.5YR, value of 4 or 5 dry, 2 or 3 moist, and chroma of 2 or 3. Typically, the horizon has fine crumb structure but has weak subangular blocky in some pedons. It is soft or slightly hard and slightly or moderately alkaline.
The Bw horizon has hue of 5YR through 10YR, value of 5 or 6 dry, 4 or 5 moist, and chroma of 3 through 5. Calcium carbonate equivalent generally ranges from 2 to 6 percent in the matrix material but there is usually evidence of carbonate movement in the form of a coating of lime overlying the surface of the bedrock. The Bw horizon is moderately or strongly alkaline.
COMPETING SERIES: These are the Fifer and Tealson series. Fifer soils have hue no redder than 10YR and contain little or no limestone gravel. Tealson soils have noncalcareous A horizons and lack limestone rock fragments.
GEOGRAPHIC SETTING: The Devoe soils are on mountain ridges and slopes at elevations of 7,500 to 9,000 feet. Slopes are 2 to 40 percent. These soils formed in thin calcareous, reddish brown sediments weathered residually from interbedded redbeds, shales, and limestones. At the type location the average annual temperature is 36 degrees F. and the average summer temperature is 48 degrees F. annual precipitation is about 18 inches with peak periods of precipitation in the spring and early summer.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Amsden and Tripit soils. Amsden and Tripit soils have argillic horizons. also, Tripit soils have a paralithic contact at depths of 20 to 40 inches.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; moderate permeability.
USE AND VEGETATION: These soils are used principally as native pastureland or for recreational purposes. Principal native vegetation is Idaho fescue, bluebunch wheatgrass, and Phlox spp.
DISTRIBUTION AND EXTENT: Mountainous areas of north-central Wyoming. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Southern Johnson County Area, Wyoming, 1971.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 9 inches (A1 horizon).
Cambic horizon - The zone from 9 to 15 inches (B2 horizon).
Paralithic contact - The boundary at 15 inches to underlying (Cr layer).
Particle-size control section - The zone from 10 to 15 inches (B2 horizon).