LOCATION MIDDLEWOOD WY+UTEstablished Series
TAXONOMIC CLASS: Clayey, smectitic, frigid Lithic Ustic Haplargids
TYPICAL PEDON: Middlewood clay loam-rangeland. (Colors are for dry soil unless otherwise stated.)
A--0 to 4 inches; light brownish gray (10YR 6/2) clay loam, dark brown (10YR 4/2) moist; strong fine granular structure; soft, very friable, sticky and slightly plastic; common fine and very fine roots; 10 percent shale channers; neutral (pH 6.8); clear smooth boundary. (2 to 6 inches thick)
Bt1--4 to 6 inches; light brownish gray (10YR 6/2) clay, dark grayish brown (10YR 4/2) moist; weak medium subangular blocky structure parting to moderate medium granular; slightly hard, friable, sticky and plastic; individual peds are very hard; common fine and very fine roots; few thin clay films on faces of peds; 10 percent shale channers; neutral (pH 6.8); clear smooth boundary. (0 to 4 inches thick)
Bt2--6 to 14 inches; brown (10YR 5/3) clay, dark brown (10YR 4/3) moist; strong fine subangular blocky structure; extremely hard, very firm, sticky and plastic; few fine and very fine roots; continuous thin clay films on faces of peds and in pores; 10 percent shale fragments; neutral (pH 6.8); abrupt wavy boundary. (6 to 16 inches thick)
R--14 inches; hard, noncalcareous, phyllitic shale.
TYPE LOCATION: Carbon County, Wyoming; near the center of sec. 12, T. 17 N., R. 88 W.
RANGE IN CHARACTERISTICS: Depth to bedrock and the lithic contact ranges from 8 to 20 inches. The mean annual soil temperature ranges from 42 to 47 degrees F., and the mean summer soil temperature ranges from 59 to 63 degrees F. The argillic horizon commonly rests directly on the bedrock, but a 2 - Middlewood Series
thin C horizon is in some pedons. Rock fragments commonly are less than 15 percent but range from 0 to 35 percent hard, phyllitic shale channers. EC is 0 to 2 mmhos throughout.
The A horizon has hue of 5Y through 7.5YR, value of 5 through 7 dry, 4 through 6 moist, and chroma of 1 through 6. It is slightly acid through mildly alkaline.
The Bt horizon has hue of 5Y through 7.5YR, value of 5 through 7 dry, 4 through 6 moist, and chroma of 1 through 6. It is clay, channery clay, clay loam or channery clay loam with 35 to 60 percent clay and up to 40 percent silt. It is slightly acid through mildly alkaline.
COMPETING SERIES: There are no other soils in this subgroup.
GEOGRAPHIC SETTING: Middlewood soils are on bedrock-controlled hillslopes, ridges, upper pediments, and dipslopes. They formed in noncalcareous residuum and colluvial slopewash derived from hard, phyllitic shale. Slopes are 2 to 40 percent. Elevations are 6,500 to 7,800 feet. The mean annual precipitation ranges from 9 to 14 inches of which about half falls as snow or rain in April, May, and early June. The mean annual temperature ranges from 38 to 44 degrees F. The frost-free season is estimated to range from 80 to 110 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Boettcher, Cushool, and Kather soils. All of these soils are moderately deep to soft shale.
DRAINAGE AND PERMEABILITY: Well drained; medium or rapid runoff; very slow permeability.
USE AND VEGETATION: Rangeland and wildlife habitat. Native vegetation consists of western wheatgrass, winterfat, bluebunch wheatgrass, big sagebrush, Indian ricegrass, and Gardner saltbush.
DISTRIBUTION AND EXTENT: Southern and south central Wyoming. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Natrona County, Wyoming; 1985.