LOCATION HOVENWEEP UTEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, active, mesic Aridic Calciustolls
TYPICAL PEDON: Hovenweep loam, rangeland. (Colors are for dry soil unless otherwise noted.)
A1--O to 2 inches; reddish brown (5YR 4/3) loam, dark reddish brown (5YR 3/3) moist; very weak thin platy structure that parts to weak fine granular; soft, very friable, slightly sticky and slightly plastic; few fine roots; vesicular pores; moderately calcareous; moderately alkaline (pH 8.0); abrupt smooth boundary. (l to 4 inches thick)
A2--2 to 5 inches; reddish brown (5YR 4/3) loam, reddish brown (5YR 4/3) moist, moderate thin platy structure; hard, friable, slightly sticky and slightly plastic; few fine roots; moderately calcareous; slightly alkaline (pH 7.7); gradual wavy boundary. (2 to 3 inches thick)
A3--5 to 10 inches; reddish brown (5YR 4/3) loam, dark reddish brown (5YR 3/3) moist; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few coarse and many fine roots; few fine and coarse pores; strongly calcareous; moderately alkaline (pH 8.0); clear wavy boundary. (4 to 15 inches thick)
Bk--10 to 15 inches; pinkish gray (7.5YR 6/2) clay loam, brown (7.5YR 4/2) moist; weak subangular blocky structure; hard, firm, slightly sticky and slightly plastic; many coarse medium and fine pores; strongly calcareous with common large veins of lime; moderately alkaline (pH 8.1); clear smooth boundary. (5 to 6 inches thick)
2C1--15 to 22 inches; light gray (2.5Y 7/2) clay loam, grayish brown (2.5Y 5/2) moist; weak subangular blocky structure; hard, firm, sticky and slightly plastic; few fine roots; very strongly calcareous; moderately alkaline (pH 8.3); gradual irregular boundary. (7 to 10 inches thick)
2C2--22 to 32 inches; light gray (2.5Y 7/2) clay loam, grayish brown (2.5Y 5/2) moist; massive; very hard, very firm, sticky and slightly plastic; very strongly calcareous; moderately alkaline (pH 8.1); clear wavy boundary. (O to 10 inches thick)
2Cr--32 to 38 inches; weathered shale.
TYPE LOCATION: San Juan County, Utah, 1/4 mile north of U.S. Highway 150 on west Summit Point Road and 100 feet east of road SW1/4 of section 31, T.33S., R.26E.
RANGE IN CHARACTERISTICS:
Thickness of the mollic epipedon: 10 to 18 inches
Depth to the calcic horizon: 10 to 18 inches
Depth to the weathered shale: 20 to 36 inches
Soil moisture: The soils are usually dry during the time that the soil temperature is above 41 degrees F. They are continuously dry in all parts of the moisture control section for 20 to 40 days during the summer solstice. The mean annual soil temperature at depth of 20 inches is 47 to 50 degrees F. Aridic ustic moisture regime.
A horizon
Value: 2 or 3 moist and 4 or 5 dry
Texture: dominantly loam but is marginal to silt loam in some pedons
Carbonates: slightly or moderately calcareous
Reaction: slightly or moderately alkaline.
Bk horizon
Hue: 10YR through 5YR
Value: 4 or 5 moist, 5 through 7 dry
Chroma: 2 through 4
Texture: clay loam, loam or silty clay loam
Carbonates: strongly calcareous
Reaction: slightly or moderately alkaline.
2C horizon
Value: 4 or 5 moist, 6 or 7 dry
Chroma: 2 through 4
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Hovenweep soils are on uplands with slopes of 2 to 10 percent. They formed in eolian deposits over shale. Elevation is 6,500 to 6,800 feet. The mean annual temperature is 45 to 48 degrees F. Average annual precipitation is 12 to 15 inches. The frost-free period is 110 to 130 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Lockerby, Menefee, Monticello, Northdale, and Ucolo soils. Lockerby soils have hue of 10YR throughout and lack calcic horizons. Menefee soils are less than 20 inches deep over shale. Monticello soils are more than 4o inches deep to bedrock and have an argillic horizon. Northdale soils have a lithic contact with sandstone at depths of 20 to 40 inches. Ucolo soils are fine and lack calcic horizons.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; slow permeability.
USE AND VEGETATION: Used for range and nonirrigated cropland. The native vegetation is dominantly pinyon, juniper, western wheatgrass, big sagebrush, black sagebrush, and some mahogany, oakbrush and bitterbrush. Crops grown are mainly winter wheat and pinto beans.
DISTRIBUTION AND EXTENT: Southeastern Utah. These soils are inextensive. MLRAs 35, 39, 48A.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: San Juan County, Utah, 1952.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from 0 to 10 inches (A horizons)
Calcic horizon - The zone from 10 to 15 inches (Bk horizon)
Paralithic contact - at 32 inches (2Cr horizon)
Classified according to Keys to Soil Taxonomy Tenth Edition, 2006