LOCATION STUBBS WYEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive Pachic Argicryolls
TYPICAL PEDON: Stubbs loam-rangeland. (Colors are for dry soil unless otherwise stated.)
A--0 to 6 inches; dark gray (10YR 4/1) loam, black (10YR 2/1) moist; strong fine granular structure; soft, very friable, moderately sticky and slightly plastic; neutral (pH 6.8); clear smooth boundary. (4 to 8 inches thick)
AB--6 to 16 inches; dark gray (10YR 4/1) loam, black (10YR 2/1) moist; weak medium prismatic structure parting to moderate medium subangular blocky; slightly hard, very friable, moderately sticky and moderately plastic; neutral (pH 7.2); clear smooth boundary. (8 to 12 inches thick)
Bt1--16 to 20 inches; grayish brown (10YR 5/2) clay loam, very dark grayish brown (10YR 3/2) moist; moderate fine prismatic structure parting to moderate fine subangular blocky; very hard, very friable, moderately sticky and moderately plastic; continuous faint clay films on faces of peds and in root channels; neutral (pH 7.2); gradual wavy boundary.
Bt2--20 to 30 inches; brown (10YR 5/3) clay loam, brown (10YR 4/3) moist; moderate fine prismatic structure parting to moderate fine subangular blocky; very hard, very friable, moderately sticky and moderately plastic; continuous faint clay films on faces of peds and in root channels; slightly alkaline (pH 7.4); gradual wavy boundary. (Combined thickness of the Bt horizon is 8 to 24 inches)
Btk--30 to 34 inches; light yellowish brown (2.5Y 6/3) clay loam, light olive brown (2.5Y 5/3) moist; weak medium subangular blocky structure; hard, very friable, moderately sticky and moderately plastic; common faint clay films on faces of peds and in root channels; strongly effervescent, lime in common soft masses; moderately alkaline (pH 8.4); gradual wavy boundary. (0 to 19 inches thick)
Cr--34 to 60 inches; weakly calcareous, soft shale and siltstone.
TYPE LOCATION: Johnson County, Wyoming; NW1/4, NW1/4, sec. 34, T. 45 N., R. 84 W.
RANGE IN CHARACTERISTICS: The mollic epipedon is 16 to 32 inches thick. Depth to calcareous material is 15 to 36 inches. The solum is 20 to 40 inches thick and usually rests on the paralithic contact. Some pedons have a thin C horizon. Depth to the paralithic contact is 20 to 40 inches. The mean annual soil temperature is 38 to 43 degrees F. Small, flat rock fragments range from 0 to 15 percent.
The A horizon has hue of 2.5Y or 10YR, value of 4 or 5 dry and 2 or 3 moist, and chroma of 1 or 2. It has granular or subangular blocky structure. This horizon is neutral or slightly alkaline.
The Bt horizon has hue of 2.5Y through 7.5YR, value of 5 or 6 dry and 3 or 4 moist, and chroma of 2 through 4. It is loam or clay loam which averages 28 to 35 percent clay. This horizon has prismatic or subangular blocky structure. It is neutral or slightly alkaline.
COMPETING SERIES: These are the Bachus, Bavdark, Benteen, Clayburn, Croydon, Crystalbutte, Davtone, Decross, Dehana, Demast, Dranburn, Dranyon, Dry Canyon, Echemoor, Hagenbarth, Millerlake, Pontuge, Senchert, Southmount, Squawval, Thulepah, Vadnais, and Winu series. Bavdark, Croydon, Crystalbutte, Decross, Dehana, Dranburn, Dry Canyon, Pontuge, Millerlake, Southmount, and Thulepah soils are more than 40 inches deep. Bachus, Benteen, Senchert, Winu, and Vadnais soils have a lithic contact at depths of less than 40 inches. Clayburn, Demast, Dranyon, and Hagenbarth soils are noncalcareous throughout. Davtone soils have hue of 5YR or 2.5YR in the Bt horizon. Squawval soils are not effervescent in any part and have paralithic materials consisting of weathered quartz monzonite in the lower part of the series control section.
GEOGRAPHIC SETTING: Stubbs soils are on mountain sides. Slopes are 2 to 25 percent. These soils formed in moderately fine textured sediments weathered residually from underlying calcareous, soft shale and siltstone. Elevation is 8,000 to 9,000 feet. The mean annual precipitation is about 18 to 24 inches, and the mean annual temperature is 35 to 41 degrees F. The frost-free season is less than 80 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Jenkinson and Turk soils. Jenkinson soils lack an epipedon and have very fine textured argillic horizons.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; moderate permeability.
USE AND VEGETATION: These soils are used for range, recreation, and wildlife habitat. Native vegetation is big sagebrush, Idaho fescue, Columbia needlegrass, King fescue, silvery lupine, and thickspike wheatgrass.
DISTRIBUTION AND EXTENT: Big Horn Mountains of north-central Wyoming. The series is of moderate extent.
MLRA OFFICE RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Johnson County (Southern Part Area), Wyoming; 1971.