LOCATION FRONTIER WYEstablished Series
TAXONOMIC CLASS: Loamy, mixed, superactive, mesic Lithic Ustic Haplargids
TYPICAL PEDON: Frontier sandy loam--rangeland. (Colors are for dry soil unless otherwise stated.)
A--0 to 4 inches; brown (10YR 5/3) sandy loam, dark brown (10YR 4/3) moist; moderate fine granular structure; soft, friable, nonsticky and nonplastic; many fine roots; slightly alkaline (pH 7.8); clear wavy boundary.
Bt1--4 to 9 inches; brown (10YR 5/3) sandy clay loam, dark brown (10YR 4/3) moist; weak medium prismatic structure parting to moderate medium subangular blocky; slightly hard, friable, slightly sticky and slightly plastic; common distinct clay bridges and few faint clay films on faces of peds; many fine roots; slightly alkaline (pH 7.8); clear wavy boundary.
Bt2--9 to 14 inches; light brown (7.5YR 6/4) clay loam, dark brown (7.5 YR 4/4) moist; weak medium prismatic structure parting to moderate medium subangular blocky; hard, friable, sticky and plastic; common distinct clay films on faces of peds; common fine roots concentrated along vertical ped faces; slightly effervescent, calcium carbonate disseminated; 10 percent angular sandstone gravel; moderately alkaline (pH 8.2); clear wavy boundary. (Combined thickness of Bt horizon is 7 to 13 inches)
Btk--14 to 17 inches; light brown (7.5YR 6/4) clay loam, dark brown (7.5YR 4/4) moist; weak medium prismatic structure parting to moderate medium subangular blocky; very hard, firm, sticky and plastic; few distinct clay films on faces of peds; common fine roots concentrated along vertical ped faces; violently effervescent, few fine threads and soft masses of calcium carbonate; 10 percent angular sandstone gravel; strongly alkaline (pH 8.6); abrupt smooth boundary. (1 to 7 inches thick)
R--17 inches; hard, calcareous, argillaceous sandstone.
TYPE LOCATION: Natrona County, Wyoming; Notches Dome Quadrangle; 880 feet south and 2,500 feet east of the northwest corner of sec. 6, T. 37 N., R. 85 W. 43 degrees 12 minutes 39 seconds north latitude and 107 degrees 5 minutes 31 seconds west longitude.
RANGE IN CHARACTERISTICS: Depth to a lithic contact ranges from 10 to 20 inches. The mean annual soil temperature is 47 to 50 degrees F.
The A horizon has value of 5 or 6 dry, 3 or 4 moist, and chroma of 2 or 3. It is slightly alkaline or moderately alkaline.
The Bt horizon has hue of 7.5YR or 10YR, value of 5 or 6 dry, and chroma of 3 or 4. It is sandy clay loam or clay loam with 25 to 35 percent clay and 30 to 60 percent fine sand or coarser. Rock fragments commonly are less than 15 percent but range to 30 percent in some pedons and are mainly angular sandstone gravel. In some pedons the Bt horizon has hue of 5YR.
The Btk horizon has the same range as the Bt horizon except it has visible accumulations of calcium carbonate and is moderately alkaline or strongly alkaline. Calcium carbonate equivalent is 5 to 15 percent.
COMPETING SERIES: These are the Berto, Bond, Bondman, and Kech series. Berto soils have a calcic horizon. Bond and Bondman soils do not have a horizon of calcium carbonate accumulation and are typically noneffervescent throughout. Kech soils have mean annual soil temperatures of more than 50 degrees F.
GEOGRAPHIC SETTING: Frontier soils are on dipslopes. Slopes range from 6 to 15 percent. They formed in residuum derived dominantly from effervescent argillaceous sandstone. Elevation is 5,500 to 6,700 feet. The mean annual precipitation is 10 to 14 inches, and the mean annual temperature is 42 to 45 degrees F. The frost-free season is 110 to 120 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Threetop and Sunup soils. Threetop soils have a lithic contact at 20 to 40 inches. Sunup soils are loamy-skeletal and do not have an argillic horizon.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; moderate permeability.
USE AND VEGETATION: Frontier soils are used for rangeland and wildlife habitat. Native vegetation is mainly bluebunch wheatgrass, western wheatgrass, mutton bluegrass, and black sagebrush.
DISTRIBUTION AND EXTENT: Central Wyoming and Colorado. The series is of limited extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Natrona County, Wyoming; 1985.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - 0 to 4 inches (A)
Argillic horizon - 4 to 14 inches (Bt1 Bt2)
Lithic contact - 17 inches (R)
MLRR- G
SIR- WY0648