LOCATION OKRIST UTEstablished Series
TAXONOMIC CLASS: Sandy, mixed, mesic Durinodic Xeric Haplocalcids
TYPICAL PEDON: Okrist sandy loam-rangeland. (Colors are for air-dry soil unless otherwise stated.)
A1--0 to 3 inches; yellowish brown (10YR 5/4) gravelly sandy loam, very dark grayish brown (10YR 3/2) moist; weak medium platy structure; soft, very friable; common very fine and fine roots; common very fine and fine tubular pores; 10 percent pebbles; moderately calcareous; 5 percent carbonates; carbonates are disseminated; moderately alkaline (pH 8.0); clear smooth boundary.
A2--3 to 8 inches; light yellowish brown (10YR 6/4) sandy loam, dark brown (l0YR 4/3) moist; weak medium platy structure; soft, very friable; common very fine and fine roots; many very fine and fine tubular pores; 5 percent pebbles; moderately calcareous (5 percent carbonate); carbonates are disseminated; moderately alkaline (pH 8.2); clear wavy boundary. (Combined thickness of the A horizon is 5 to 10 inches).
Bqk1--8 to 19 inches; light yellowish brown (10YR 6/4) loamy sand, yellowish brown (10YR 5/4) moist; weak medium subangular blocky structure; slightly hard, friable; common very fine and fine roots; many very fine and common fine tubular pores; 5 percent pebbles; 5 percent durinodes; common thin silica coatings on ped faces and the undersides of rock fragments; moderately calcareous (10 percent carbonates); carbonates are disseminated and in thin coatings on the undersides of rock fragments; strongly alkaline (pH 8.6); clear wavy boundary.
Bqk2--19 to 30 inches; very pale brown (10YR 7/4) loamy sand; yellowish brown (10YR 5/4) moist; massive; hard, very firm; few very fine roots; common very fine and fine tubular pores; 5 percent pebbles; common thin silica coatings on the undersides of rocks; brittle matrix; moderately calcareous (10 percent carbonate); carbonates are disseminated and in thin coatings on the undersides of rock fragments; strongly alkaline (pH 8.6); clear wavy boundary. (Combined thickness of the Bqk horizon is 20 to 40 inches)
Ck--30 to 55 inches; light yellowish brown (10YR 6/4) sand, yellowish brown (10YR 5/4) moist; massive; soft, friable; moderately calcareous (12 percent carbonate) carbonates are disseminated; strongly alkaline (pH 8.6) clear way boundary. (0 to 20 inches thick)
C--55 to 60 inches; very pale brown (10YR 7/3) sand, pale brown (10YR 6/3) moist; single grain; loose; moderately calcareous (5 percent carbonate); carbonates are disseminated; strongly alkaline (pH 8.8).
TYPE LOCATION: Box Elder County, Utah; about 1 mile northeast of Birch Canyon; 700 feet north and 2,600 feet east of the southwest corner of sec. 30, T. 6 N., R. 18 W.
RANGE IN CHARACTERISTICS: The particle-size control section ranges from 2 to 10 percent clay and from 0 to 30 percent rock fragments.
The mean annual soil temperature is 48 to 53 degrees F. The moisture control section is usually dry, but is moist in some part 25 to 40 percent of the time the soil temperature is above 41 degrees F. It is dry in all parts for 45 to 60 consecutive days following the summer solstice.
The A horizon has value of 5 to 7 dry, 3 to 5 moist and chroma of 2 to 4. It is mildly alkaline to strongly alkaline.
The B horizon has value of 6 or 7 dry, 4 to 6 moist and chroma of 2 to 4. It is loamy sand, gravelly sand or sand. Durinodes range from 5 to 30 percent about half of which are strongly cemented. Moist consistence in the B horizon ranges from friable to very firm, but is firm and brittle in some part of the horizon when there is less than 20 percent durinodes. It is moderately calcareous or strongly calcareous and moderately alkaline or strongly alkaline.
The C horizon has value of 5 to 7 dry or moist and chroma of 3 or 4. It is gravelly coarse sand, sand, or gravelly sand. The C horizon is moderately calcareous or strongly calcareous and strongly alkaline or very strongly alkaline.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: The Okrist soils are on fan terraces at elevations of 4,500 to 5,200 feet. Slopes are l to l0 percent. These soils formed in sandy, ancient beach deposits. The mean annual temperature is 46 to 51 degrees F. The average annual precipitation is 8 to 12 inches. The freeze-free period is about 120 to 160 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Cliffdown, Hiko Peak, Hiko Springs, Shabliss, and Skumpah soils. The Hiko Peak and Cliffdown soils formed in mixed alluvium on terraced bajadas and have a loamy-skeletal particle-size control section. Hiko Springs soils are coarse-loamy, do not have brittle matrix in any horizon and are on terraced bajadas. The Shabliss soils are on the dissected bajada above the high lake terrace and have a continuously cemented duripan. The Skumpah soils are on a lake plain and have a natric horizion.
DRAINAGE AND PERMEABILITY: Well drained; slow runoff; moderate permeability.
USE AND VEGETATION: These soils are used for rangeland. The potential vegetation is black sagebrush, Wyoming big sagebrush, spiny hopsage, spiny horsebrush and Indian ricegrass.
DISTRIBUTION AND EXTENT: Okrist soils are located in northwest Utah and are of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Box Elder County, Utah-Western Part, 1984
REMARKS: Diagnostic horizons or features recognized in this pedon are:
Calcic horizon - from 8 to 55 inches (Bqk1, Bqk2, Ck horizons).
Durinodic feature - from 19 to 30 inches brittle and very firm (Bqk2 horizon).
The classification is based on the "Keys to Soil Taxonomy, Eighth Edition, 1998".