LOCATION PAVILLION WYEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Typic Haplocambids
TYPIFYING PEDON: Pavillion sandy clay loam, native grassland. (Colors are for dry soil unless otherwise noted.)
A1--0 to 3 inches; light brownish gray (10YR 6/2) sandy clay loam, dark grayish brown (10YR 4/2) moist; moderate fine granular structure; soft, very friable; mildly alkaline (pH 7.8); clear smooth boundary. (2 to 4 inches thick)
B21--3 to 7 inches; brown (10YR 5/3) sandy clay loam, dark brown (10YR 4/3) moist; moderate coarse prismatic structure that parts to moderate medium subangular blocks; hard, friable; mildly alkaline (pH 7.8); gradual wavy boundary. (0 to 8 inches thick)
B22--7 to 22 inches; brown (10YR 5/3) sandy clay loam, dark brown (10YR 4/3) moist; weak coarse prismatic structure that parts to moderate medium subangular blocks; hard, very friable; few thin glossy patches on the vertical faces of peds; few gravel fragments; calcareous; moderately alkaline (pH 8.2); gradual wavy boundary. (11 to 22 inches thick)
C1ca--22 to 32 inches; light brownish gray (10YR 6/2) sandy clay loam, dark grayish brown (10YR 4/2) moist; massive; hard, very friable; few scattered pebbles; some visible secondary calcium carbonate occurring as concretions, and in thin seams and streaks; calcareous; moderately alkaline (pH 8.4); clear wavy boundary. (4 to 27 inches thick)
IIC2--32 to 60 inches; calcareous sedimentary rock, principally sandstone and sandy shale.
TYPE LOCATION: Fremont County, Wyoming; NE1/4 SE1/4 sec. 34, T.3N., R.1E.
RANGE IN CHARACTERISTICS: Usually these soils are leached to a depth of 7 or 8 inches but depth to calcareous material ranges from 0 to 12 inches. Thickness of solum ranges from 15 to 24 inches, and depth to bedrock ranges from 20 to 40 inches. Weighted average organic content of the surface 15 inches ranges from .3 to .5 percent. The sand/clay ratio ranges from 2 to 4. The control section is typically sandy clay loam, but clay ranges from 18 to 35 percent, silt from 5 to 30 percent, and sand from 45 to 70 percent with more than 35 percent fine sand or coarser. Coarse fragments range from 0 to 15 percent but are usually less than 10 percent. Mean annual soil temperature ranges from 47 degrees to 51 degrees F., and mean summer soil temperature from 60 degrees to 68 degrees F. The A1 horizon has hue of 2.5Y or 10YR, value of 6 or 7 dry and 4 or 5 moist, and chroma of 2 or 3. It is neutral to moderately alkaline (pH 7.0 to 8.0). This horizon usually has granular or crumb structure, but it has alkaline (pH 7.0 to 8.0). This horizon usually has granular or crumb structure, but it has hue of 2.5Y through 7.5YR value of 5 or 6 dry and 4 or 5 moist, and chroma of 3 or 4. It is mildly or moderately alkaline (pH 7.8 to 8.4). The Cca horizon has hue of 2.5Y or 10YR. It is moderately or strongly alkaline (pH 8.0 to 8.6), and has 2 to 10 percent calcium carbonate equivalent. There are a few crystals of calcium sulfate immediately above the bedrock in some pedons.
COMPETING SERIES AND THEIR DIFFERENTIAE: These are the Kinnear, Wall, and Saddle series. Kinnear soils lack a paralithic contact at depths of less than 40 inches. Wall soils have a coarse-loamy control section. Saddle soils have an argillic horizon.
SETTING: Pavillion soil are on gently to moderately sloping upland hills and ridges. Slope gradients range from 2 to about 20 percent. They formed in moderately thick, calcareous parent sediments weathered residually from sedimentary bedrock or locally transported and redeposited over bedrock. At the type location, the mean annual precipitation is 7 inches, with peak periods of precipitation in the spring and summer months. Mean annual temperature is 43 degrees F., mean summer temperature is 66 degrees F.
PRINCIPAL ASSOCIATED SOILS: These are the Apron, and Griffy soils. Apron soils lack bedrock above 40 inches. Griffy soils have an argillic horizon and lack bedrock above 40 inches.
DRAINAGE AND PERMEABILITY: Well-drained; medium runoff; moderate permeability.
USE AND VEGETATION: These soils are used principally as native pastureland or as irrigated cropland. Principal native plants are big sage, needleandthread, and Indian ricegrass.
DISTRIBUTION AND EXTENT: Basin areas of central and northern Wyoming. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Fremont County (Riverton Irrigated Area), Wyoming, 1969.