LOCATION HOBOG UT+NV
Established Series
Rev. RSJ/MJD/WWJ
09/2015
HOBOG SERIES
The Hobog series consists of very shallow and shallow, well drained soils that formed in material weathered from sandstone or limestone. They are on ridges and mesa remnants. Slope is 2 to 50 percent. The mean annual precipitation is about 7 inches and the mean annual temperature is about 64 degrees F.
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, thermic Lithic Haplocalcids
TYPICAL PEDON: Hobog very cobbly loam - rangeland. (Colors are for air dry soil unless otherwise noted.)
A--0 to 4 inches; reddish brown (5YR 5/4) very cobbly loam, reddish brown (5YR 4/4) moist; weak medium subangular blocky structure (topmost 1/4 inch has weak thin platy structure); slightly hard, friable, slightly sticky and slightly plastic; few fine roots; few fine tubular pores; slightly effervescent, carbonates are disseminated; strongly alkaline (pH 8.6); clear smooth boundary. (2 to 6 inches thick)
Bk--4 to 13 inches; reddish yellow (5YR 6/6) very flaggy loam, reddish brown (5YR 4/4) moist; massive; slightly hard, friable, sticky and plastic; few fine roots; few fine tubular pores; moderately calcareous, carbonates are mainly disseminated and as pendants on underside of flagstones; moderately alkaline (pH 8.3); abrupt wavy boundary. (6 to 14 inches thick)
R--13 inches; sandstone.
TYPE LOCATION: Washington County, Utah; about 3 miles southeast of St. George; about 400 feet north and 1,200 feet east of the SE corner of sec. 34, T. 42 S., R 15 W; St. George Quadrangle; lat. 37 degrees 4 minutes 57 seconds N. and long. 113 degrees 31 minutes 37 seconds W.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature: 59 to 67 F.
Mean summer soil temperature: 77 to 82 degrees F.
The soils are dry in all parts of the moisture control section 75 to 85 percent of the time the soil temperature is above 41 degrees F., unless irrigated. The soil moisture regime is Typic Aridic.
Depth to bedrock: 6 to 20 inches
Rock fragments: 35 to 75 percent gravel and flagstones
Reaction: slightly alkaline to strongly alkaline
A horizon
Hue: 5YR or 7.5YR
Value: 5 through 8 dry, 4 or 5 moist
Chroma: 3 or 4
Texture: very cobbly loam to gravelly fine sandy loam.
Bk horizon
Hue: 5YR or 7.5YR
Value: 6 through 8 dry, 4 or 5 moist
Chroma: 3 to 6
Texture: very flaggy loam or very cobbly clay loam.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Hobog soils are on ridges and mesa remnants at elevations of 1,600 to 4,500 feet. Slopes range from 2 to 50 percent. These soils formed in residuum weathered from sandstone or limestone. The mean annual temperature is 57 to 70 degrees F., and the mean summer temperature is 80 to 84 degrees F. The average annual precipitation ranges from 5 to 12 inches. The frost-free period is 180 to 240 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Renbac and
Tobler soils. Renback soils have an argillic horizon and lack a calcic horizon. Tobler soils are more than 40 inches deep to bedrock, have fine sandy loam texture and lack a calcic horizon.
DRAINAGE AND PERMEABILITY: Well-drained; rapid runoff; moderate permeability.
USE AND VEGETATION: Used as rangeland. Vegetation is bursage, blackbrush, creosotebush, Mormon tea, yellowbrush, desert almond, filaree and cheatgrass.
DISTRIBUTION AND EXTENT: Southern Utah, Southern Nevada and Northern Arizona. The series is of small extent. MLRA 30.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: PHOENIX, ARIZONA
SERIES ESTABLISHED: Washington County, Utah, 1972.
REMARKS: Diagnostic horizons and features in this pedon include:
Ochric epipedon - from 0 to 4 inches (A horizon).
Calcic horizon - from 4 to 13 inches (BK horizon).
Classified according to Soil Taxonomy Second Edition, 1999
In Utah this series is correlated with Desert range sites.
The classification was changed from Lithic Calciorthids to Lithic Haplocalcids in June 1994.
Responsibility for this series was transferred from Davis to Phoenix 4/2015. The last revision to the series was 6/2005. ET
National Cooperative Soil Survey
U.S.A.