LOCATION HILLFIELD UT+IDEstablished Series
TAXONOMIC CLASS: Coarse-silty, mixed, superactive, mesic Typic Calcixerepts
TYPICAL PEDON: Hillfield silt loam - cultivated; (Colors are for dry soil unless otherwise noted.)
Ap--0 to 6 inches; brown (10YR 5/3) silt loam, dark brown (10YR 4/3) moist; moderate medium and fine granular structure; slightly hard, very friable, slightly sticky, slightly plastic; common medium and fine roots; many medium pores; strongly calcareous; slightly alkaline. (pH 7.8); gradual wavy boundary. (2 to 8 inches thick)
Bk1--6 to 12 inches; pale brown (10YR 6/3) silt loam, dark brown (10YR 4/3) moist; weak medium and fine subangular blocky structure; slightly hard, friable, slightly sticky, slightly plastic; common medium and fine roots; many medium pores; strongly calcareous; slightly alkaline (pH 7.8); gradual wavy boundary. (6 to 25 inches thick)
Bk2--12 to 21 inches; pale brown (10YR 6/3) silt loam, dark brown (10YR 4/3) moist; weak medium subangular blocky structure; slightly hard, friable, slightly sticky, slightly plastic; few fine roots; few fine pores; strongly calcareous; moderately alkaline (pH 7.9); gradual wavy boundary. (6 to 18 inches thick)
C--21 to 60 inches; very pale brown (10YR 7/3) stratified very fine sandy loam and clay loam; common medium distinct strong brown mottles, brown (10YR 5/3) moist; moderate thick platy structure; slightly hard, friable, sticky, plastic; few pores; strongly calcareous; moderately alkaline (pH 8.1).
TYPE LOCATION: Davis County, Utah; 850 feet north and 500 feet east of the S 1/4 corner of sec. 14, T.4N., R.lW.
RANGE IN CHARACTERISTICS: The moisture regime is Xeric bordering on Aridic.
The average texture of the 10 to 40 inch control section is silt loam with less than 18 percent clay and less than 15 percent coarser than very fine sand. The laminated lake terrace materials extend to within a few inches of the surface in some pedons.
The A horizon has hue of 10YR or 7.5YR, value of 5 through 7 dry and 3.5 to 5 moist, and chroma of 2 or 3. It is slightly to strongly calcareous. This horizon contains 1 to 3 percent organic matter.
The Bk horizon has hue of 10YR, 7.5YR, or 2.5Y, value of 5 through 8 dry, and 4 through 7 moist, and chroma of 2 through 6.
The C horizon has hue of 10YR, 7.5YR, or 2.5Y, value of 5 through 7 dry, and 4 through 6 moist, and chroma of 2 through 6. It is often quite stratified, ranging from fine sand to clay loam or silty clay loam.
COMPETING SERIES: This is the Heglar (ID) series. Heglar soils contain 20 to 25 percent hard nodules in the Bk horizon and have a cambic horizon.
GEOGRAPHIC SETTING: Hillfield soils are on lake terraces and escarpments with slopes of 4 to 60 percent. They formed in lake sediments from a mixture of rocks, dominantly quartzite, gneiss, granite, limestone, and sandstone. The climate is dry subhumid. The mean annual temperature ranges from 45 to 53 degrees F., and the average summer temperature ranges from 66 to 72 degrees F. The average annual precipitation ranges from 12 to 16 inches. The frost-free season ranges from 100 to 175 days. Elevation is 4,200 to 5,200 feet.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Ackmen, Parleys, and Timpanogas soils. All have mollic epipedons. Parleys soils have silty clay loam argillic horizons. Timpanogos soils have loam argillic horizons. Ackmen soils lack horizons of carbonate accumulation.
DRAINAGE AND PERMEABILITY: Well-drained; medium to rapid runoff; moderate to slow permeability.
USE AND VEGETATION: Rangeland and cultivated land. The cultivated areas are on slopes of up to 30 percent and are used for both dry and irrigated cropland. The dry farmed areas are in alfalfa or small grains. Under irrigation, forage crops and orchards are the principal crops. The native vegetation is mainly big sagebrush, oakbrush, western wheatgrass, Indian ricegrass, three awn grass, sand dropseed, and cheatgrass.
DISTRIBUTION AND EXTENT: These soils are extensive in central and northern Utah and southern Idaho. MLRA 13 and 28A
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Davis County, Utah, 1972.
REMARKS: Diagnostic horizons and features recognized in this pedon:
Calcic horizon - the zone from 6 to 21 inches (Bk, and Bk2 horizons).
The classification is based on the "Keys to Soil Taxonomy, Eighth Edition, 1998". Mottling in the 21 to 60 inch zone is assumed to be relict.