LOCATION WHEELRIDGE CATentative Series
TAXONOMIC CLASS: Mixed, thermic Xeric Torripsamments
TYPICAL PEDON: Wheelridge gravelly loamy sand in an almond orchard, with a north-facing slope of 2.5 percent, at an elevation of 1,200 feet. (Colors are for dry soil unless otherwise stated. When described on March 6, 1989, the soil was moist throughout).
Ap--0 to 7 inches; grayish brown (10YR 5/2) gravelly loamy sand, dark brown (10YR 3/3) moist; weak fine and medium subangular blocky structure parting to weak medium platy; soft, very friable, nonsticky and nonplastic; common very fine and few fine and medium roots; common very fine interstitial pores; 20 percent gravel 2 to 35 mm in diameter; very slightly effervescent; disseminated carbonates; neutral (pH 7.2); abrupt smooth boundary. (6 to 10 inches thick)
A--7 to 13 inches; grayish brown (10YR 5/2) gravelly loamy sand, dark brown (10YR 3/3) moist; weak fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; few very fine, fine, medium, and coarse roots; many very fine interstitial pores; 25 percent gravel 2 to 35 mm in diameter; slightly effervescent disseminated carbonates; moderately alkaline (pH 8.4); clear smooth boundary. (0 to 8 inches thick)
Bk1--13 to 27 inches; light brownish gray (10YR 6/2) gravelly loamy sand, dark brown (10YR 4/3) moist; massive; soft, very friable, nonsticky and nonplastic; few very fine, fine, medium and coarse roots; many very fine interstitial pores; 25 percent gravel 2 to 35 mm in diameter; strongly effervescent disseminated carbonates and segregated as thin pendents on coarse fragments; strongly alkaline (pH 8.6); clear wavy boundary.
Bk2--27 to 44 inches; light brownish gray (10YR 6/2) cobbly loamy sand, dark brown (10YR 4/3) moist; massive; soft, very friable, nonsticky and nonplastic; few very fine, fine, medium, and coarse roots; many very fine and few fine interstitial pores; 15 percent cobbles and 15 percent gravel; strongly effervescent disseminated carbonates and segregated as thin pendents on coarse fragments; strongly alkaline (pH 9.0); abrupt wavy boundary. (Combined thickness of the Bk horizons is 28 to 52 inches)
2Bk3--44 to 65 inches; very pale brown (10YR 7/3) extremely gravelly sand, brown (10YR 5/3) moist; single grain; loose, nonsticky and nonplastic; few very fine, fine, and medium roots; many very fine and few fine interstitial pores; 65 percent gravel 2 to 75 mm in diameter; violently effervescent disseminated carbonates and segregated as thin pendents on coarse fragments; strongly alkaline (pH 9.0); clear wavy boundary.
TYPE LOCATION: Kern County, California; about 28 miles south of downtown Bakersfield, 3,000 feet east of Interstate 5 and 1,250 feet north of the California Aqueduct; 1,500 feet north and 1,350 feet east of the southwest corner of Sec. 5, T. 10 N., R. 19 W., SBB&M; 34 degrees, 58 minutes, 27 seconds north latitude and 118 degrees, 55 minutes, 50 seconds west longitude; Grapevine quadrangle.
RANGE IN CHARACTERISTICS:
Soil temperature - Average annual: 61 to 65 degrees F and the soil temperature is never below 47 degrees F.
Soil moisture - dry throughout from mid May to mid December and is never moist more than 90 consecutive days.
It is moist 90 to 110 cumulative days.
Electrical conductivity: 0 to 2 mmhos/cm throughout
Sodium absorption ratio: less than 5 throughout
Ap and A horizons
Value: 5 or 6 dry, 3 or 4 moist
Chroma: 2, 3, or 4
Clay content: 2 to 8 percent
Organic matter: 0.5 to 0.8 percent
Rock fragments: 15 to 35 percent gravel
Effervescence: noneffervescent to slightly
Reaction: neutral to moderately alkaline
Bk horizons
Value: 6 or 7 dry, 4 or 5 moist
Chroma: 2, 3 or 4
Clay content: 2 to 8 percent
Rock fragments: 15 to 35 percent including 10 to 35 percent gravel and 0 to 20 percent cobbles
Effervescence: strongly or violently
Reaction: moderately alkaline or strongly alkaline
2Bk horizon
Value: 6 or 7 dry, 4 or 5 moist
Chroma: 3 or 4
Clay content: 0 to 5 percent
Rock fragments: 60 to 80 percent with 60 to 75 percent gravel and 0 to 5 percent cobbles
Effervescence: strongly or violently
Reaction: moderately alkaline or strongly alkaline
COMPETING SERIES: These are the Cinco and Whitewolf series. Cinco soils are on very steep uplands and have soil temperatures below 47 degrees F. during the winter. Whitewolf soils do not have segregated carbonates and they have less than 15 percent gravel throughout.
GEOGRAPHIC SETTING: Wheelridge soils are on fan terraces. Slopes are 0 to 5 percent. The soils formed in alluvium derived from mixed rock sources. Elevations are 950 to 1500 feet. The climate is arid with hot dry summers and cool, somewhat moist winters. The mean annual precipitation is 6 to 9 inches. The mean annual temperature is 60 to 64 degrees F. Mean January temperature is about 46 degrees F. and mean July temperature is about 84 degrees F. The frost-free season is 250 to 300 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Whitewolf soils and the Guijarral (T), Hesperia, and Premier soils. Guijarral soils are on similar landforms and are coarse-loamy. Hesperia and Premier soils are on nearby alluvial fans and are coarse-loamy.
DRAINAGE AND PERMEABILITY: Somewhat excessively drained; slow runoff; rapid permeability.
USE AND VEGETATION: Used primarily for irrigated crops such as almonds, grapes, oranges, grapefruit, lemons, and wheat. Native vegetation includes allscale saltbush, red brome, fillaree, and other annual grasses and forbs.
DISTRIBUTION AND EXTENT: Along the rim of the Southern San Joaquin Valley of California. The series is not extensive. MLRA is 17.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES PROPOSED: Kern County, California, 1990. The name is from nearby Wheeler Ridge.
REMARKS: Diagnostic horizons and features recognized in the profile are:
Ochric epipedon -- the zone from the soil surface to 13 inches (Ap, A).
Particle size control section - the zone from 10 to 40 inches.