LOCATION SPLITRO WY+ID MTEstablished Series
TAXONOMIC CLASS: Loamy, mixed, superactive Lithic Haplocryolls
TYPICAL PEDON: Splitro sandy loam, on a west facing 7 percent slope in grassland. (Colors are for dry soil unless otherwise stated).
A--0 to 8 inches; brown (7.5YR 5/3) sandy loam, dark brown (7.5YR 3/3) moist; moderate fine granular structure; soft, very friable, nonsticky and nonplastic; many fine and very fine roots; many fine and very fine pores; scattered sandstone fragments on the surface; neutral (pH 6.8); clear smooth boundary. (6 to 15 inches thick)
Bw--8 to 16 inches; brown (7.5YR 5/4) fine sandy loam, brown (7.5YR 4/4) moist; moderate coarse subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic 5 percent sandstone gravel; neutral (pH 6.8); abrupt smooth boundary. (4 to 10 inches thick)
R--16 inches; hard quartzitic sandstone.
TYPE LOCATION: Johnson County, Wyoming; NE1/4, NE1/4, Sec. 30, T45N, R85W. Tabletop Quadrangle. 43 degrees 50 minutes 38 seconds north latitude and 107 degrees 6 minutes 34 seconds west longitude.
RANGE IN CHARACTERISTICS: The mollic epipedon ranges from 7 to 15 inches thick, the solum ranges from 10 to 20 inches thick, and depth to bedrock ranges from 10 to 20 inches. The particle size control section is sandy loam or fine sandy loam. Rock fragments range from 0 to 35 percent. The average annual soil temperature ranges from 38 degrees to 43 degrees F. and mean summer soil temperature from 45 degrees to 59 degrees F.
The A horizon has hue of 10YR or 7.5YR, value of 3 through 5 dry, 2 or 3 moist, and chroma of 2 or 3. It is slightly acid to slightly alkaline.
The Bw horizon, has hue of 10YR through 5YR, value of 4 through 6 dry, 3 through 5 moist, and chroma of 2 through 5. This horizon is slightly acid to slightly alkaline.
COMPETING SERIES: These are the Dickle, Hanagita, Hazton, Heisspitz, Jenkinson, Lotex, Paddy, Skisams, Spliten, Taylow, Trump, Tuggle, and Udelope series. Dickle and Paddy soils are 25 to 35 percent clay throughout. Jenkinson and Trump soils have calcium carbonate accumulations in some part of the profile. Hanagita soils have silt loam textures. Hazton soils have a high percentage of medium and coarse angular granitic sand and have C horizons that are very hard when dry. Heisspitz and Skisams soils have more than 18 percent clay in the particle size control section. Lotex soils have hue of 5YR or redder. Spliten and Udelope soils receive most of their moisture in the winter and early spring. Taylow soils have a xeric moisture regime. Tuggle soils have a paralithic contact above the lithic contact.
GEOGRAPHIC SETTING: Splitro soils are on upland hillslopes, mountain slopes, structural benches and ridges. Slope gradients range from 0 to 65 percent. These soils formed in medium textured alluvium, residuum, and eolian materials derived dominantly from sandstone. In Colorado some areas are derived from basalt. Precipitation is 18 to 25 inches, with peak periods of precipitation occurring in the spring and early summer. Mean annual temperature is 36 to 40 degrees F. Elevation is 6,500 to 9,200 feet. The frost-free season is 60 to 90 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Passcreek and Sawcreek soils. Both of these soils are moderately deep and occur on lowland hillslope positions and broad summits.
DRAINAGE AND PERMEABILITY: Well drained; slow to rapid runoff; moderate to rapid permeability.
USE AND VEGETATION: These soils are used principally as native pastureland or for recreational purposes. Native vegetation is green needlegrass, Idaho fescue, and yarrow. May have scattered ponderosa pine and quaking aspen.
DISTRIBUTION AND EXTENT: The Bighorn Mountain areas of north-central Wyoming and the western slope of Colorado. The series is of moderate extent.
MLRA OFFICE RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Lower Colorado Area, Colorado 1970.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
mollic epipedon - 0 to 8 inches (A)
cambic horizon - 8 to 16 inches (Bw)
lithic contact - 16 inches (R)
MLRR- E
SIR- WY0062, WY0845, WY1390