LOCATION LAMBMAN WYEstablished Series
TAXONOMIC CLASS: Loamy, mixed, superactive, mesic, shallow Aridic Argiustolls
TYPICAL PEDON: Lambman loam-rangeland. (Colors are for dry soil unless otherwise stated.)
A--0 to 3 inches; dark grayish brown (10YR 4/2) loam, very dark grayish brown (10YR 3/2) moist; moderate fine and very fine granular structure; slightly hard, very friable, slightly sticky and slightly plastic; common fine and very fine roots; common fine interstitial pores, few fine random tubular pores; neutral (pH 7.3); clear smooth boundary. (1 to 5 inches thick)
Bt1--3 to 10 inches; brown (10YR 4/3) clay loam, dark brown (10YR 4/3) clay loam, dark brown (10YR 3/3) moist; strong coarse and medium subangular blocky structure; hard, friable, sticky and plastic; common fine and very fine roots; few fine random tubular pores; common thin clay films on faces of peds; mildly alkaline (pH 7.5); clear smooth boundary.
Bt2--10 to 14 inches; brown (10YR 5/3) clay loam, brown (10YR 4/3) moist; strong medium and fine subangular blocky structure; hard, friable, sticky and plastic; few fine roots; few fine random tubular pores; common thin clay films on faces of peds; mildly alkaline (pH 7.6); gradual wavy boundary. (8 to 16 inches thick)
Bw--14 to 18 inches; brown (10YR 5/3) loam, brown (10YR 4/3) moist; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; mildly alkaline (pH 7.7); abrupt wavy boundary. (0 to 5 inches thick)
Cr--18 to 60 inches; weakly consolidated, noncalcareous sandstone many feet thick.
TYPE LOCATION: Goshen County, Wyoming; 265 feet east and 1,520 feet north of the SW corner of sec. 2, T. 30 N., R. 65 W.
RANGE IN CHARACTERISTICS: Depth to bedrock and paralithic contact ranges from 10 to 20 inches. The mollic epipedon ranges from 5 to 14 inches thick. The mean annual soil temperature is 49 to 53 degrees F. The soils are dry for more than 60 consecutive days and 80 cumulative days in the moisture control section during July 15 through October 31. Coarse fragment content is less than 15 percent throughout the profile. These soils typically lack salts more soluble than gypsum throughout but EC may range from 0 to 2 in some subsoils and substrata.
The A horizon has hue of 10YR or 2.5Y, value of 4 or 5 dry, 2 or 3 moist, and chroma of 2 or 3. It is neutral through moderately alkaline.
The Bt horizon has hue of 10YR, 2.5Y, or 7.5YR, value of 4 through 6 dry, 2 through 4 moist, and chroma of 2 or 3. Texture is clay loam, sandy clay loam, or loam with 20 to 35 percent clay. It is neutral through moderately alkaline.
The Bw, Bc, or Bk horizons, if present, have hue of 10YR, 2.5Y, or 7.5YR, value of 4 through 6 dry, 3 through 6 moist, and chroma of 2 through 4. Carbonates range from 0 to 10 percent. Textures are clay loam, loam, or sandy loam with some pedons having a thin loam sand immediately above the bedrock. It is neutral through moderately alkaline.
The bedrock consists of either calcareous or noncalcareous, weakly consolidated sandstone many feet thick. The soil-bedrock interface inhibits root penetration and is considered to be a paralithic contact.
COMPETING SERIES: There are no other soils in this class.
GEOGRAPHIC SETTING: Lambman soils are on uplands. They formed in mixed slope alluvium and residuum derived from weakly consolidated sandstone. Slopes are 0 to 20 percent. Elevations are 3,500 to 5,900 feet. The mean annual precipitation ranges from 10 to 17 inches of which about half falls as snow or rain in late March, April, May, and early June. The frost-free season is estimated to range from 110 to 137 days.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; moderately slow permeability.
USE AND VEGETATION: Rangeland and wildlife habitat. Native vegetation consists of western wheatgrass, blue grama, bluebunch wheatgrass, needleandthread, and threadleaf sedge.
DISTRIBUTION AND EXTENT: North central and southeastern Wyoming. The series is of limited extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Goshen County (Northern Part), Wyoming; 1974.
REMARKS: Diagnostic horizons and properties recognized in this pedon are:
1. Mollic epipedon - 0 to 10 inches (A, Bt1)
2. Argillic horizon - 3 to 14 inches (Bt1, Bt2)
3. Paralithic contact - 18 inches (Cr)
4. Soil temperature at a depth of 20 inches is 41 degrees or warmer from May 15 to October 15 in most years.