LOCATION GUBEN UT+COEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Aridic Calciustolls
TYPICAL PEDON: Guben gravelly loam--rangeland. (Colors are for air-dry soil unless otherwise stated.)
A1--0 to 1 inch; grayish brown (10YR 5/2) gravelly loam, very dark grayish brown (10YR 3/2) moist; weak fine granular structure; soft, friable, slightly sticky and slightly plastic; common fine roots; common fine interstitial pores; 30 percent gravel; slightly calcareous; neutral (pH 7.0); abrupt smooth boundary. (1 to 4 inches thick)
A2--1 to 4 inches; brown (10YR 4/3) gravelly loam, dark brown
(10YR 3/3) moist, crushed; weak medium platy structure parting to weak very fine granular; soft, very friable; many very fine and fine roots; few very fine pores; 30 percent gravel; slightly calcareous; neutral (pH 7.0); clear smooth boundary. (2 to 4 inches thick)
ABt--4 to 10 inches; brown (10YR 4/3) gravelly loam, dark brown
(10YR 3/3) moist, crushed; weak medium and coarse subangular blocky structure parting to weak fine subangular blocky; slightly plastic; very fine and fine roots; few very fine pores; common thin clay bridges; 30 percent gravel; slightly calcareous; neutral (pH 7.0); clear smooth boundary. (4 to 8 inches thick)
Bt--10 to 14 inches; brown (10YR 5/3) gravelly sandy clay loam,
dark brown (10YR 4/3) moist, crushed; weak coarse and medium subangular blocky structure parting to weak fine subangular blocky; slightly hard, friable, slightly sticky and slightly plastic; common very fine and fine roots; few very fine pores; few thin clay films in pores; 30 percent gravel and 5 percent cobbles; strongly calcareous; mildly alkaline (pH 7.5) gradual wavy boundary. (0 to 9 inches thick)
Btk--14 to 22 inches; grayish brown and light gray (10YR 5/2 and
7/2) extremely gravelly sandy clay loam, dark grayish brown (10YR 4/2) moist, crushed; weak medium angular and subangular blocky structure parting to weak fine subangular blocky; slightly hard, friable, slightly sticky and slightly plastic; common fine and very fine roots; few very fine pores; few thin clay bridges; 50 percent gravel and 20 percent cobbles; strongly calcareous; mildly alkaline (pH 7.5); gradual wavy boundary. (0 to 9 inches thick)
Bk1--22 to 40 inches; light gray (10YR 7/2) very gravelly sandy clay loam, brown (10YR 5/3) moist, crushed; massive; loose, friable; few fine roots; 10 percent cobbles and 50 percent gravel; strongly calcareous; mildly alkaline (pH 7.7); clear smooth boundary. (10 to 20 inches thick)
Bk2--40 to 44 inches; white (10YR 8/2) very gravelly loam, light
gray (10YR 7/2) moist; weak and moderate thin platy structure; laminar in some parts and weakly to strongly cemented; slightly sticky and slightly plastic; few fine roots in fractures; few fine tubular pores; 50 percent gravel and 10 percent cobbles; strongly calcareous; moderately alkaline (pH 8.0); abrupt smooth boundary. (0 to 6 inches thick)
C3--44 to 60 inches; light gray (10YR 7/2) extremely gravelly sandy loam, grayish brown (10YR 5/2) moist, single grain; loose; few very fine roots; common medium and large interstitial pores; 50 percent gravel and 15 percent cobbles; strongly calcareous; moderately alkaline (pH 8.0).
TYPE LOCATION: Garfield County, Utah; Tom Best Spring Road, southeast 1/4, sec. 21, T. 35 S., R. 4 W.
RANGE IN CHARACTERISTICS: The mollic epipedon ranges from 7 to 13 inches thick. The depth to the calcic horizon ranges from 10 to 24 inches. Rock fragments average 35 to 60 percent in the particle size control section. The mean annual soil temperature is about 42 to 47 degrees F, and the mean summer soil temperature at depth of 20 inches is about 59 to 64 degrees F. The soils are moist in some parts of the moisture control section for 50 to 60 percent of the time the soil temperature is above 41 degrees F. These soils are slightly calcareous to strongly calcareous in the A horizon.
The A and ABt horizons have hue of 7.5YR or 10YR, value of 4 or 5 dry, 2 or 3 moist and chroma of 2 to 4 dry and 2 or 3 moist.
The Bt and Btk horizons have hue of 7.5YR or 10YR, value of 4 to 7 dry and 2 or 3 moist and chroma of 2 to 4. They range from gravelly, very gravelly and extremely gravelly sandy loam to gravelly, very gravelly and extremely gravelly clay loam, very stony loam and very cobbly loam. It is mildly alkaline or moderately alkaline.
The Bk horizon has hue of 7.5YR or 10YR, value of 4 to 8 dry and chroma of 2 to 4. It ranges from very gravelly and very cobbly loamy sand to very gravelly, very cobbly sandy clay loam, very stony loam, very cobbly loam, and very cobbly fine sandy loam. It is moderately alkaline or strongly alkaline.
COMPETING SERIES: These are the Eagar, Tosca (T) and Winspect (T) series. Eagar and Winspect soils lack a cambic horizon. Tosca soils contain less than 12 percent clay in the particle size control section.
GEOGRAPHIC SETTING: Guben soils formed on stream terraces and in a thick mantle of mixed volcanic alluvium on pediment surfaces. The relief is nearly level to steep. Elevations range from 5,800 to 9,500 feet. The mean annual precipitation is 12 to 20 inches and the freeze-free period ranges from 60 to 120 days. The mean annual temperature is 38 to 45 degrees F, and the mean summer temperature is 59 to 62 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Circleville, Datino, and Showalter soils. Circleville soils have bedrock between 20 to 40 inches. Datino soils are noncalcareous in the upper part. Showalter soils have an argillic horizon with 35 percent or more clay.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; moderate permeability.
USE AND VEGETATION: Rangeland. Native vegetation is mainly black sagebrush and rabbitbrush.
DISTRIBUTION AND EXTENT: South-central part of Utah and northwestern Colorado. (Approximately 1,757 acres in Rio Blancho County, Colorado) This series is inextensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Paunsaugunt Survey Area, Utah, 1969.
REMARKS: These soils were formerly classified as Calcisols. Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon -the zone from the surface to 10 inches (A1, A2,
ABt horizons)
Calcic horizon -the zone from 14 to 44 inches (Btk, Bk1, Bk2 horizons)
Cambic horizon -the zone from 10 to 14 inches (Bt horizon)