LOCATION COCHORA CAEstablished Series
TAXONOMIC CLASS: Loamy, mixed, superactive, calcareous, thermic, shallow Typic Torriorthents
TYPICAL PEDON: Cochora loam, on an east-facing slope of 20 percent under annual grasses and shrubs at an elevation of 1,675 feet. (When described on November 19, 1990, the soil was dry throughout; Colors are for dry soil unless otherwise stated).
A1--0 to 5 cm (0 to 2 inches); light gray (2.5Y 7/2) loam, olive brown (2.5Y 4/4) moist; moderate medium platy structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine roots; common very fine tubular pores; 10 percent gravel; non-effervescent; slightly alkaline (pH 7.5); clear smooth boundary.
Bw--5 to 23 cm (2 to 9 inches); light gray (10YR 7/2) loam, yellowish brown (10YR 5/4) moist; weak medium and coarse angular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine roots; common very fine tubular pores; 10 percent gravel; slightly effervescent disseminated carbonates; moderately alkaline (pH 8.0); clear wavy boundary. (The A horizon is 5 to 23 cm (2 to 9 inches) thick)
C--23 to 38 cm (9 to 15 inches); pale yellow (2.5Y 8/2) sandy loam, light olive brown (2.5Y 5/4) moist; massive; slightly hard, very friable, slightly sticky and slightly plastic; few very fine roots; common very fine tubular pores; 10 percent gravel; strongly effervescent with disseminated carbonates; moderately alkaline (pH 8.0); abrupt wavy boundary. (15 to 36 (6 to 14 inches) thick)
Cr--38 cm (15 inches); massive weakly consolidated sediment; slakes in water within minutes; works up to a silty clay loam; roots do not penetrate, can be dug by a spade; violently effervescent with disseminated carbonates; 10 percent subrounded gravel from shale and chert.
TYPE LOCATION: Kern County, California; on the eastern foothills of the Temblor Range about 9.5 km (6 miles) northwest of the town of Taft; 160 meters (525 feet) north and 260 meters (850 feet) east of the southwest corner of Sec. 6, T. 32 S., R. 23. E, MDB&M; 35 degrees, 9 minutes, 48 seconds north latitude and 119 degrees, 33 minutes, 6 seconds west longitude; Fellows quadrangle.
RANGE IN CHARACTERISTICS:
Soil temperature - Average annual: 17 to 19 degrees C. (62 to 67 degrees F.) and the soil temperature is never below 8 degrees C. (47 degrees F.).
Soil moisture - dry throughout from mid April to mid December and moist in some or all parts during the rest of the year.
Depth to soft bedrock: 36 to 50 cm (14 to 20 inches)
Particle size control section:
Clay content: averages 7 to 18 percent
Rock fragments: 5 to 20 percent
The A horizon has a color of 10YR 6/3, 7/2, 7/3, 8/2, 8/3 or 2.5Y 7/2. Moist color is 10YR 4/3, 5/3, 5/4, 6/4 or 2.5Y 5/4. The texture us predominantly loam, but may also be sandy loam, fine sandy loam, gravelly loam or gravelly sandy loam. It has 10 to 18 percent clay and 0 to 20 percent gravel. Reaction is slightly or moderately alkaline. It is noneffervescent to violently effervescent with disseminated carbonates.
The Bw horizon has a color of 10YR 6/3, 7/2, 7/3, 7/4, 8/2, 8/3 or 2.5Y 7/2 or 8/2. Moist color is 10YR 4/3, 5/3, 5/4, 6/4, 7/4 or 2.5Y 5/4 or 6/4. The texture us predominantly loam, but may also be sandy loam, fine sandy loam, gravelly loam or gravelly sandy loam. It has 10 to 18 percent clay and 0 to 20 percent gravel. Reaction is moderately alkaline. It is strongly or violently effervescent with disseminated carbonates.
The C horizon has a color of 10YR 6/3, 7/2, 7/3, 8/2, 8/3 or 2.5Y 7/2. Moist color is 10YR 4/3, 5/3, 6/3, or 2.5Y 5/4. The texture us loam, sandy loam, gravelly loam or gravelly sandy loam. It has 4 to 18 percent clay and 0 to 20 percent gravel. Reaction is moderately alkaline. It is effervescent to violently effervescent with disseminated carbonates.
COMPETING SERIES: These are the Randsburg and Chinkle soils. Randsburg soils are formed from granite and have segregated or cemented carbonates at the upper boundary of the Cr horizon. Chinkle soils are moist in the control section following summer convection storms, are less than 14 inches deep and have hues of 10YR or redder.
GEOGRAPHIC SETTING: Cochora soils are on summits, shoulders and predominantly south facing backslopes of hills. Slopes range from 9 to 50 percent. The soils formed in soft material weathered from diatomite, sandstone, siltstone, shale or conglomerate. Elevations are 305 to 854 meters (1,000 to 2,800 feet). The climate is semiarid with hot dry summers and cool, moist winters. The mean annual precipitation is 152 to 229 mm (6 to 9 inches). The mean annual temperature is 15 to 18 degrees C. (59 to 64 degrees F.). Mean July temperature is about 27 degrees C. (81 degrees F.), and mean January temperature is about 7 degrees C. (44 degrees F.). The frost-free season is 240 to 300 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bitterwater and Pyxo soils. Bitterwater soils are deep on cooler aspects and toe slopes. Pyxo soils are moderately deep and are on backslopes.
DRAINAGE AND PERMEABILITY: Well drained; medium or rapid runoff; moderate permeability.
USE AND VEGETATION: Used for livestock grazing, oil fields, and wildlife habitat. The vegetation is dominantly red brome, filaree and allscale saltbush.
DISTRIBUTION AND EXTENT: Eastern foothills of the Temblor Range in Southern California. The series is not extensive. MLRA 15.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES PROPOSED: Kern County, California, 1990. The name is from the nearby Cochora Ranch.
REMARKS: Diagnostic horizons and features recognized in the profile are:
Ochric epipedon - 0 to 23 cm (0 to 9 inches) (A1, Bw)
Cambic horizon - 5 to 23 cm (2 to 9 inches) (Bw)
Paralithic contact - 38 cm (15 inches)
The cambic horizon does not extend below 25 cm (10 inches) which excludes the soil from Aridisols.
Particle size control section -- the zone from 25 to 38 cm (10 to 15 inches)