LOCATION OAKCITY UTEstablished Series
TAXONOMIC CLASS: Fine, mixed, superactive, calcareous, mesic Xerertic Torriorthents
TYPICAL PEDON: Oakcity loam, 0 to 2 percent slopes, rangeland. (Colors are for air-dry soil unless otherwise noted.)
A1--0 to 5 inches; pale brown (10YR 6/3), loam, brown (10YR 4/3) moist; weak fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and common fine roots; common very fine vesicular pores; slightly effervescent; 10 percent calcium carbonate equivalent; strongly alkaline (pH 8.8); abrupt smooth boundary. (2 to 15 inches thick)
A2--5 to 10 inches; very pale brown (10YR 7/3) clay loam, brown (10YR 5/3) moist; moderate fine subangular blocky structure; hard, friable, slightly sticky and slightly plastic; common very fine and common fine roots; common very fine and common fine tubular pores; strongly effervescent; 12 percent calcium carbonate equivalent; strongly alkaline (pH 8.8); abrupt smooth boundary. (0 to 10 inches thick)
Bw1--10 to 15 inches; very pale brown (10YR 7/3) silty clay loam, brown (10YR 5/3) moist; moderate medium subangular blocky structure; hard, firm, sticky and plastic; common very fine and fine roots; common very fine and fine tubular pores; strongly effervescent; 16 percent calcium carbonate equivalent; strongly alkaline (pH 8.8); clear smooth boundary. (0 to 5 inches thick)
Bw2--15 to 31 inches; very pale brown (10YR 7/3) silty clay, pale brown (10YR 6/3) moist; weak fine subangular blocky structure; hard, firm, sticky and plastic; common very fine and fine roots; common very fine tubular pores; strongly effervescent; 17 percent calcium carbonate equivalent; strongly alkaline (pH 8.6); clear smooth boundary. (10 to 18 inches thick)
C1--31 to 47 inches; very pale brown (10YR 7/3) silty clay, light yellowish brown (10YR 6/4) moist; massive; hard, firm, very sticky and very plastic; common very fine and fine roots; common very fine vesicular pores; strongly effervescent; 18 percent calcium carbonate equivalent; strongly alkaline (pH 8.6); clear smooth boundary. (14 to 34 inches thick)
C2--47 to 60 inches; very pale brown (10YR 7/3) silty clay, pale brown (10YR 6/3) moist; massive; hard, firm, very sticky and very plastic; strongly effervescent; 18 percent calcium carbonate equivalent; moderately alkaline (pH 8.4).
TYPE LOCATION: Millard County, Utah; located about 2 miles south of Leamington; 2400 feet north and 1200 feet east of the southwest corner of section 23, Township 15 South, Range 4 West; Lynndyl, Utah quadrangle; latitude: 39 degrees 30 minutes 8 seconds N. and longitude: 112 degrees 16 minutes 7 seconds W.
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 47 to 54 degrees F., and the mean summer soil temperature is 70 to 75 degrees F. The soil moisture regime is Aridic bordering on Xeric.
The particle size control section averages 35 to 50 percent clay. Calcium carbonate equivalent is 15 to 30 percent. Depth to bedrock is more than 60 inches.
The A horizon has hue of 7.5YR or 10YR, value of 6 or 7 dry or 4 or 5 moist, and chroma of 2 through 4 moist or dry. Texture is loam or clay loam. Reaction is moderately alkaline or strongly alkaline.
The Bw and C horizons have hue of 10YR, value of 6 or 7 dry or 5 or 6 moist, and chroma of 2 through 4 moist or dry. Texture is silty clay loam, silty clay, or clay. Conductivity of the saturation extract is 2 to 8 millimhos/cm, but may range as high as 16 millimhos/cm below a depth of 50 inches. Reaction is moderately alkaline through very strongly alkaline. The Bw horizons don't meet the definition of a cambic.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: The Oakcity soils are on lake plains and lake terraces at elevations of 4400 to 5000 feet. Slopes are 0 to 2 percent. The soils formed in alluvium and lake sediments primarily derived from sedimentary rocks. The climate is semiarid. The mean annual air temperature is 45 to 52 degrees F. and the average annual precipitation is 8 to 12 inches. Frost free period is 120 to 140 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Berent, Heist, and Jigsaw soils. The Berent soil is sandy and on semi-stabilized dunes. The Heist soils have less than 18 percent clay in the particle size control section. The Jigsaw soils are on similar landscape positions to the Oakcity soils, but have less than 35 percent clay in the particle size control section.
DRAINAGE AND PERMEABILITY: Well drained, slow runoff, slow permeability.
USE AND VEGETATION: These soils are used for irrigated crop and hayland, a few areas are used for range. Principal crops are alfalfa, small grains, and silage corn. Potential native vegetation is bluebunch wheatgrass and Wyoming big sagebrush.
DISTRIBUTION AND EXTENT: South central Utah; MLRA 28A. Oakcity soils are of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Millard County, Utah; Millard County, Eastern Part Soil Survey, 1995.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - the zone from the soil surface to a depth of 10 inches. (A1, A2 horizons)
Particle size control section - the zone from 10 to 40 inches.
Xerertic subgroup placement is based on an estimated linear extensibility of 6 to 7. The linear extensibility was derived from a nomograph in "Aids for Estimating Soil Properties Significant to Engineering Interpretation - Utah 1973."
The classification is based on the "Keys to Soil Taxonomy, Eighth Edition, 1998".