LOCATION OLJETO UTEstablished Series
TAXONOMIC CLASS: Sandy-skeletal, mixed, mesic Typic Haplocalcids
TYPICAL PEDON: Oljeto loamy fine sand, rangeland. (Colors are for air dry soil unless otherwise noted.)
C1--O to 20 inches; red (2.5YR 5/6) loamy fine sand; red (2.5YR 4/8) moist; weak medium subangular blocky structure, soft, very friable, nonsticky and nonplastic; few medium, common fine pores; 5 percent fine gravel; moderately alkaline (pH 8.2); clear wavy boundary. (16 to 24 inches thick)
Ck--20 to 40 inches; light red (2.5YR 6/6) very gravelly loamy coarse sand; red (2.5YR 4/8) moist; single grained; loose; few medium and fine roots; few fine pores; 60 percent fine gravel; strongly calcareous lime disseminated and as thin coatings on bottom side of rock fragments; moderately alkaline (pH 8.4); gradual wavy boundary. (16 to 24 inches thick)
C2--40 to 60 inches; red (2.5YR 5/6) very gravelly loamy sand; red (2.5YR 4/8) moist; single grained; loose; few medium and fine roots; few fine pores; 70 percent fine gravel; moderately calcareous, lime disseminated; moderately alkaline (pH 8.4).
TYPE LOCATION: San Juan County, Utah; 2 miles southwest of Oljeto Trading Post; SW1/4 SW1/4 section 26, T.42S., R.14E.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature: 54 degrees to 59 degrees F.
Mean summer soil temperature: 74 degrees to 79 degrees F.
Soil moisture: The soils are dry in all parts above the base of the moisture control section for 75 to 85 percent of the time. Typic aridic moisture regime.
C1 horizon
Color: red to light red
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 6 through 8 moist
Reaction: slightly or moderately alkaline
Gravel content: 0 to 10 percent
Ck horizon
Hue: 2.5YR or 5YR
Value: 6 or 7 dry, 4 or 5 moist
Chroma: 6 through 8 moist
Texture: very gravelly loamy coarse sand to very gravelly sand
Gravel content: 50 to 70 percent
Reaction: moderately or strongly alkaline.
C2 horizon
Hue: 2.5YR or 5YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 6 through 8 moist
Texture: very gravelly loamy sand to very gravelly sand
Gravel content: 50 to 70 percent
Reaction: moderately or strongly alkaline.
COMPETING SERIES: These are the Aysees (NV) and Loray (NV) series. Aysees and Loray soils have hue of 10YR or yellower.
GEOGRAPHIC SETTING: Oljeto soils are on old alluvial fans and terraces at elevations of 4,800 to 5,300 feet. Slope gradients are 1 to 8 percent. These soils formed in mixed alluvium from sandstone and shale. The climate is arid and the average annual precipitation ranges from 6 to 10 inches. The mean annual temperature is 52 degrees to 56 degrees F. The mean summer temperature is 72 degrees to 77 degrees F. and the frost-free period ranges from 150 to 180 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Neskahi, Sheppard, and Nepalto soils. Neskahi, Nepalto and Sheppard soils lack calcic horizons and contain less than 15 percent rock fragments. Neskahi soils average very fine sandy loam in the series control section. Sheppard soils average fine sand in the series control section.
DRAINAGE AND PERMEABILITY: Somewhat excessively drained; medium runoff; rapid permeability.
USE AND VEGETATION: Oljeto soils are used as rangeland. Vegetation is blackbrush, Mormon tea, galleta grass and blue grama grass.
DISTRIBUTION AND EXTENT: Southeastern Utah. Oljeto soils are inextensive.
MLRA 35.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: San Juan County, Utah, 1976.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: The zone from 0 to 20 inches. (C1 horizon)
Calcic horizon: The zone from 20 to 40 inches. (Ck horizon)
Classified according to Soil Taxonomy Second Edition, 1999.