LOCATION TOBISH UTEstablished Series
TAXONOMIC CLASS: Fine, mixed, superactive, mesic Ustic Haplargids
TYPICAL PEDON: Tobish very cobbly clay loam - rangeland (Colors are for air dry soil unless otherwise noted.)
Al--0 to 1 inches; brown (7.5YR 5/4) very cobbly light clay loam, dark brown (7.5YR 4/3) moist; moderate very fine granular structure; soft, friable, slightly sticky, plastic; many very fine interstitial pores; 75 percent cobbles and gravel; mildly alkaline (pH 7.4); clear smooth boundary. (l to 3 inches thick)
Blt--1 to 5 inches; dark brown (7.5YR 4/4) cobbly heavy clay loam, dark brown (7.5YR 4/4) moist; weak medium prismatic structure that parts to moderate medium and fine angular blocky structure; hard, firm, sticky, plastic; few fine and very fine roots; few very fine tubular, and many very fine interstitial pores; 30 percent cobbles and gravel; few thin clay films on faces of peds; mildly alkaline (pH 7.6); gradual smooth boundary. (2 to 5 inches thick)
B21t--5 to 17 inches; brown (7.5YR 5/4) gravelly heavy clay loam, dark brown (7.5YR 4/4) moist; moderate medium prismatic structure that parts to moderate medium and fine angular blocky structure; hard, very firm, sticky, very plastic; few medium, fine and very fine roots; few fine, common very fine tubular and interstitial pores; 20 percent gravel, common thin clay films on faces of peds and in pores; mildly alkaline (pH 7.4); gradual smooth boundary. (5 to 22 inches thick)
B22t--17 to 31 inches; yellowish red (5YR 5/6) gravelly light clay, yellowish red (5YR 4/6) moist; moderate coarse prismatic structure that parts to moderate coarse angular blocky structure; very hard, very firm, very sticky, very plastic; few fine and very fine roots; common very fine tubular and interstitial pores; 20 percent gravel, many thin clay films on faces of peds and in pores; mildly alkaline (pH 7.4); gradual wavy boundary. (0 to 14 inches thick)
B3--31 to 35 inches; yellowish red (5YR 5/6) sandy clay loam, yellowish red (5YR 4/6) moist; weak coarse subangular blocky structure; very hard, firm, sticky, plastic; few fine and very fine roots; few very fine tubular pores; few thin clay films on faces of peds and in pores; slightly calcareous; moderately alkaline (pH 8.3); gradual smooth boundary. (0 to 6 inches thick)
R--35 inches; weathered sandstone.
TYPE LOCATION: Washington County, Utah; about 1/2 mile north of Diamond Valley; approximately 400 feet east and 160 feet south of the N1/4 corner of sec. 35, T.40S., R.16W.
RANGE IN CHARACTERISTICS: The solum is 22 to 35 inches thick over bedrock. The mean annual soil temperature ranges from 50 to 57 degrees F., and the mean summer soil temperature from 69 to 72 degrees F. The soils are usually dry during the period the soil temperature is above 41 degrees F. They are moist in some parts of the moisture control section for 30 to 40 days during the summer months and are dry for 70 to 85 days during the 120 days following the winter solstice. The soils are mildly or moderately alkaline and are noncalcareous to depths of 30 inches or more.
The Al horizon has hue of 7.5YR or 5YR, value of 3 or 4 moist and chroma of 2 through 4. It ranges from very cobbly light clay loam to very cobbly sandy loam.
The B2t horizon has hue of 7.5YR, 5YR, or 2.5YR, value of 3 through 5 dry, 3 or 4 moist, and chroma of 4 through 6. It ranges from gravelly heavy clay loam to cobbly clay or sandy clay and contains 20 to 40 percent rock fragments. This horizon ranges from 13 to 26 inches thick.
COMPETING SERIES: These are the Bew, Cerrillos, Lonti, Malposa, Norrest, Panky, Poley, Renohill, Silver, and Thurlow series. Bew, Cerrillos, Lonti, Panky, Poley, Silver and Thurlow soils are more than 40 inches deep to bedrock. Malposa soils are calcareous throughout. Bew, Cerrillos, Panky, Renohill, Silver and Thurlow soils have horizons of carbonate accumulation at depths of less than 30 inches. Norrest soils have a paralithic contact at depths of 20 to 40 inches.
GEOGRAPHIC SETTING: Tobish soils are on gently sloping to steep mountain slopes at elevations of 4,100 to 5,000 feet. Slopes range from 2 to 30 percent. These soils formed in residuum weathered from sandstone and shale. The mean annual temperature is 48 to 57 degrees F., and the mean summer temperature is 70 to 73 degrees F. The average annual precipitation is 10 to 13 inches. Frost-free period is 160 to 170 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Yaki soils. Yaki soils lack argillic horizons are are less than 20 inches deep to a lithic contact.
DRAINAGE AND PERMEABILITY: Well-drained; medium runoff; slow permeability.
USE AND VEGETATION: Used as rangeland. Vegetation is blackbrush, sagebrush, pinyon, and juniper.
DISTRIBUTION AND EXTENT: Southern Utah. The series is inextensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Washington County, Utah, 1972.
OSED scanned by NSSQA. Last revised by state 4/72.