LOCATION CURRENT SPRING UTEstablished Series
TAXONOMIC CLASS: Clayey-skeletal, smectitic, mesic Typic Argixerolls
TYPICAL PEDON: Current Spring gravelly loam. (Colors are for air-dry soil unless otherwise stated)
A1--0 to 5 inches; grayish brown (10YR 5/2) gravelly loam, very dark grayish brown (10YR 3/2) moist; weak fine granular structure; slightly hard, friable, slightly sticky, slightly plastic; many very fine and fine roots; few very fine vesicular pores; 25 percent gravel; neutral (pH 6.8); abrupt smooth boundary. (0 to 5 inches thick)
A2--5 to 13 inches; grayish brown (10YR 5/2) gravelly clay loam, dark brown (7.5YR 3/2) moist; weak fine and medium subangular blocky structure; slightly hard, friable, slightly sticky, slightly plastic; many very fine and fine roots; few very fine tubular pores; 35 percent gravel; neutral (pH 6.8); clear smooth boundary. (2 to 11 inches thick)
Bt1--13 to 24 inches; brown (7.5YR 5/4) very gravelly clay loam; brown to dark brown (7.5YR 4/4) moist; moderate fine subangular blocky structure; hard, firm, moderately sticky, moderately plastic; common very fine and fine roots, and few medium roots; few very fine tubular pores; few thin clay films on ped faces; 35 percent gravel; neutral (pH 7.0); clear smooth boundary. (8 to 24 inches thick)
Bt2--24 to 41 inches; light brown (7.5YR 6/4) very gravelly clay; brown to dark brown (7.5YR 4/4) moist; moderate medium subangular blocky structure; very hard, very firm, moderately sticky, moderately plastic; common very fine and fine roots, and few fine tubular pores; moderate thin clay films on ped faces; 40 percent gravel and 10 percent cobbles; neutral (pH 7.2); clear smooth boundary. (15 to 30 inches thick)
Bt3--41 to 60 inches; light brown (7.5YR 6/4) very gravelly clay loam; brown to dark brown (7.5YR 4/4) moist; weak fine subangular blocky structure; hard, firm, moderately sticky, moderately plastic; few very fine tubular pores; few thin clay films on ped faces; 40 percent gravel and 10 percent cobbles; neutral (pH 7.2).
TYPE LOCATION: Millard County, Utah; 6 miles east of Holden; 2000 feet east and 1500 feet north of the southwest corner of section 10, T.20 S, R.3 W.
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 48 to 54 dgrees F., the mean summer soil temperature is 65 to 72 degrees F. The soil moisture control section is dry for 60 to 90 consecutive following the summer solstice. The moisture regime is xeric bordering on aridic.
The mollic epipedon ranges from 10 to 18 inches. Depth to the argillic horizon is 10 to 20 inches. The particle size control section averages 35 to 50 percent clay and 35 to 50 percent rock fragments.
The A horizon has hue of 7.5YR or 10YR, value of 4 or 5 dry, 2 or 3 moist, and chroma of 2 or 3 dry and moist. It is gravelly loam or cobbly loam with 15 to 35 percent rock fragments. It is neutral to mildly alkaline.
The Bt horizon has hue of 7.5YR or 10YR, value of 5 or 6 dry, 3 to 5 moist, and chroma of 3 or 4 dry and moist. It is very gravelly clay loam, very gravelly clay or very cobbly clay with 35 to 45 percent gravel and 5 to 15 percent cobbles. It is neutral to mildly alkaline.
COMPETING SERIES: These are the Ada (ID), Fiddler (CA), Hiibner (UT), Immig (OR), and Provig (OR) series. Ada soils have sandy C horizons and the combined thickness of the A and B horizons is less than 45 inches. Fiddler and Imig soils have basalt at 20 to 40 inches. Hiibner soils are dry for 60 to 75 consecutive days following the summer solstice and the particle size control section contains more than 60 percent rock fragments. Provig soils have a combined thickness of the A and B horizons of less than 20 inches and a mean annual soil temperature of 54 to 56 degrees F.
GEOGRAPHIC SETTING: Current Spring soils are on alluvial fans and low hillslopes. Slopes are 5 to 50 percent. These soils formed in alluvium primarily from quartzite, conglomerate and limestone. These soils occur at elevations of 5400 to 6500 feet. The climate is subhumid, having a mean annual temperature of 46 to 52 degrees F. The average annual precipitation is 14 to 16 inches. The freeze-free period is 100 to 150 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Borvant, Collard, Donnardo, Flowell, Pavant and Red Butte soils. Borvant and Pavant soils lack a Bt horizon and have a petrocalcic horizon. Collard soils have less than 35 percent clay in the control section. Donnardo and Flowell soils have a calcic horizon. Red Butte soils are cobbly throughout.
DRAINAGE AND PERMEABILITY: Well drained; medium to very rapid runoff; slow permeability.
USE AND VEGETATION: Current spring soils are used mainly for rangeland and wildlife habitat. The potential vegetation is bluebunch wheatgrass, big sagebrush, bluegrasses and needleandthread.
DISTRIBUTION AND EXTENT: Central Utah. MLRA 28A. It is 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:
Mollic epipedon - the zone from the surface of the soil to 13 inches (A1, A2 horizons).
Argillic horizon - the zone from 13 to 60 inches (Bt1, Bt2, Bt3 horizons).
The classification is based on the "Keys to Soil Taxonomy, Eighth Edition, 1998".