LOCATION BENTAXLE UTEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, carbonatic, mesic Lithic Calcixerepts
TYPICAL PEDON: Bentaxle gravelly loam -- rangeland. Gravel and cobbles cover 25 percent of the surface. (Colors are for air-dry soil unless otherwise noted.)
A1--0 to 3 inches; brown (10YR 5/3) gravelly loam; very pale brown (10YR 7/4) dry; weak medium subangular blocky structure parting to moderate medium granular; soft, friable, slightly sticky, slightly plastic; few fine roots, and common very fine roots; violently effervescent; moderately alkaline (pH 8.4); 55 percent calcium carbonate equivalent; 20 percent gravel; clear smooth boundary.
A2--3 to 5 inches; pale brown (10YR 6/3) gravelly loam; very pale brown (10YR 7/4) dry; moderate medium subangular blocky structure; hard, friable, slightly sticky, slightly plastic; few very fine roots; few very fine tubular pores; violently effervescent; strongly alkaline (pH 8.6); 60 percent calcium carbonate eqivalent; carbonates are disseminated; 20 percent gravel; clear wavy boundary.
Bk1--5 to 14 inches; pale brown (10YR 6/3) very cobbly loam; very pale brown (10YR 8/4) dry; weak medium subangular blocky structure; slightly hard, firm, moderately sticky, moderately plastic; few very fine roots; violently effervescent; strongly alkaline (pH 8.8); 70 percent calcium carbonate equivalent; calcium carbonates are in concretions and filaments; 35 percent gravel; 25 percent cobbles; gradual smooth boundary.
Bk2--14 to 19 inches; very pale brown (10YR 7/3) very gravelly fine sandy loam; very pale brown (10YR 8/4) dry; weak fine subangular blocky structure; slightly hard, firm, slightly sticky, slightly plastic; few very fine roots; violently effervescent; strongly alkaline (pH 8.8); 75 percent calcium carbonate equivalent; calcium carbonates are segregated in filaments and masses; 30 percent gravel; 15 percent cobbles; abrupt wavy boundary.
R--19 inches; fine grained calcareous sandstone.
TYPE LOCATION: Millard County, Utah; 10 miles west of Nephi; about 200 feet south and 1200 feet west of the northeast corner of Section 27, T. 17 S., R. 2 W.
RANGE IN CHARACTERISTICS: Mean annual soil temperature is 47 to 51 degrees F. These soils are moist, in the soil moisture control section, more than one-half the time that the soil temperature is above 41 degrees F.; but are dry for 60 or more consecutive days in the 4 months following the summer solstice in 6 or more of 10 years. The soil moisture regime is Xeric bordering on aridic.
The depth to bedrock ranges from 10 to 20 inches. The particle size control section contains 18 to 27 percent clay and 35 to 60 percent rock fragments. Calcium carbonate equivalent is 40 to 80 percent.
The A horizon has value of 5 through 7 dry, 3 through 5 moist, and chroma of 2 to 4. Texture is gravelly loam or stony loam. Rock fragment content is 15 to 35 percent. Reaction is moderately or strongly alkaline.
The Bk horizon has hue of 7.5YR or 10YR, value of 6 through 8 dry, 4 through 7 moist, and chroma of 2 to 4. Texture is very gravelly loam, very cobbly loam, very gravelly fine sandy loam, or very cobbly fine sandy loam. Rock fragment content is 35 to 60 percent. Calcium carbonate equivalent is 40 to 80 percent. Reaction is moderately alkaline or strongly alkaline.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Bentaxle soils are on hill slopes, mountain slopes and ridges at elevations of 5,300 to 6700 feet. Slopes are 15 to 70 percent. The soils formed in residuum and colluvium from limestone and sandstone. Mean annual temperature is 45 to 49 degrees F. and average annual precipitation is 12 to 16 inches. Frost-free period is 90 to 130 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Borvant, Donnardo, Lodar, and Spager soils. The Borvant soil has a mollic epipedon and a petrocalcic horizon within 20 inches of the soil surface. The Donnardo soil has a mollic epipedon and is very deep. The Lodar soil has a mollic epipedon. The Spager soil has a petrocalcic horizon within 20 inches of the soil surface.
DRAINAGE AND PERMEABILITY: Somewhat excessively drained; rapid runoff; moderately rapid permeability.
USE AND VEGETATION: Used for rangeland and grazed woodland. Potential vegetation is singleleaf pinyon pine, Utah juniper, black sagebrush, bluebunch wheatgrass, Indian ricegrass, and needleandthread.
DISTRIBUTION AND EXTENT: Western Utah. MLRA 28A. This series is of moderate 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 that are recognized in this pedon are:
Ochric epipedon - the layer from the soil surface to a depth of 5 inches. (A1, A2 horizons)
Calcic horizon - the layer from 5 to 19 inches. (Bk1, Bk2 horizons)
Lithic contact - bedrock contact at 19 inches. (R horizon)
The classification is based on the "Keys to Soil Taxonomy, Eighth Edition, 1998".