LOCATION TOEHEAD UTEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Cumulic Haploxerolls
TYPICAL PEDON: Toehead silt loam--cultivated. (Colors are for air-dry soil unless othewise stated.)
Ap--0 to 7 inches; dark grayish brown (10YR 4/2) silt loam, very dark grayish brown (10YR 3/2) moist; weak medium subangular blocky structure; hard, firm, sticky and plastic; few fine, medium and very fine roots; few fine pores; slightly calcareous, carbonates are disseminated; neutral (pH 7.2); clear smooth boundary. (5 to 7 inches thick)
A--7 to 14 inches; dark grayish brown (10YR 4/2) silt loam, dark brown (10YR 3/3) moist; moderate medium subangular blocky structure; very hard, firm, sticky and plastic; few fine and medium roots; common fine and very fine pores; slightly calcareous, carbonates are disseminated; neutral (pH 7.2); clear smooth boundary. (7 to 11 inches thick)
Bw--14 to 22 inches; brown (10YR 4/3) silty clay loam, dark brown (10YR 3/3) moist; weak medium prismatic structure, parting to moderate medium angular blocky; very hard, firm, sticky and plastic; few very fine roots; common fine pores; slightly calcareous, carbonates are disseminated; moderately alkaline (pH 8.2); gradual wavy boundary. (8 to 10 inches thick)
Bk1--22 to 28 inches; brown (10YR 5/3) silty clay loam, dark brown (10YR 3/3) moist; moderate medium angular blocky structure; extremely hard, firm, sticky and plastic; few fine and very fine roots; few fine and very fine pores; moderately calcareous, carbonates are disseminated and in fine veins; moderately alkaline (pH 8.2); gradual wavy boundary. (0 to 8 inches thick)
Bk2--28 to 41 inches; light brownish gray (10YR 6/2) silty clay loam, dark grayish brown (10YR 4/2) moist; moderate fine angular blocky structure; very hard, firm, sticky and plastic; few very fine roots; few very fine pores; moderately calcareous, carbonates are disseminated and in common fine veins; moderately alkaline (pH 8.4); gradual smooth boundary. (10 to 13 inches thick)
Bk3--41 to 70 inches; light brownish gray (10YR 6/2) silty clay loam, dark grayish brown (10YR 4/2) moist; massive; very hard, firm, sticky and plastic; few very fine and fine roots; few very fine pores; moderately calcareous, carbonates are disseminated and in veins and nodules; moderately alkaline (pH 8.4).
TYPE LOCATION: Sanpete County, Utah; 3 miles north of the town of Fairview, east of Railroad tracks, 1,815 feet east and 330 feet north of the southwest corner of sec. 13, T. 13 S., R. 4 E.
RANGE IN CHARACTERISTICS: The mollic epipedon is 20 to 30 inches thick. Organic matter content decreases irregularly with depth or remains above 0.5 percent above 50 inches. The particle size control section is clay loam to silty clay loam with 27 to 35 percent clay. The mean annual soil temperature at 20 inches ranges from 45 to 47 degrees F. The mean summer soil temperature ranges from 59 to 61 degrees F. In more than 7 out of 10 years the soils are moist in all parts of the moisture control section about 55 percent of the time soil temperature at 20 inches is above 41 degrees F., and are moist for 65 to 75 consecutive days during the 120 days after the winter solstice.
The A and Bw horizons have a value of 2 or 3 moist and 4 or 5 dry, and chroma of 2 or 3. They are neutral to moderately alkaline.
The Bk horizon has hue of 10YR or 7.5YR, value of 5 to 8 dry, 3 to 6 moist, and chroma of 2 to 4. This horizon is mildly alkaline to strongly alkaline.
COMPETING SERIES: These are the Koosharem and Zola series. Koosharem soils are in an aridic moisture regime and have less than 27 percent clay in the particle size control section. Zola soils are moderately well drained and have mottles below 36 inches.
GEOGRAPHIC SETTING: Toehead soils are on alluvial fans at elevations of 5,200 to 6,800 feet. Slope ranges from 2 to 8 percent. Parent materials are alluvium from limestone, quartzite, sandstone, and shale. The climate is dry subhumid and the average annual precipitation ranges from 14 to 18 inches. The mean annual temperature is 42 to 45 degrees F. The mean summer termperature is 63 to 67 degrees F., and the freeze-free period ranges from 90 to 110 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Ant Flat, Ayoub, Canburn and Lizzant soils. Canburn soils are poorly drained and have characteristics of wetness - mottles or low chroma at depths of 20 to 30 inches. Lizzant soils have more than 35 percent coarse fragments in the particle size control section. Ant Flat soils have mollic epipedon less than 20 inches thick. Ayoub soils have bedrock at depths of 20 to 40 inches.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; moderately slow permeability.
USE AND VEGETATION: These soils are used for range and for growing irrigated alfalfa, small grain, and pasture. Vegetation is oakbrush, big sagebrush, and bluebunch wheatgrass.
DISTRIBUTION AND EXTENT: Central Utah; the series is not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Sanpete Soil Survey Area, Utah, 1971.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - the zone from the surface of the soil to a depth of approximately 28 inches. (Ap, A1, Bw, Bk1 horizons)