LOCATION LEWKALB                 CA

Established Series
Rev. MV/JFR/KKC/ET
09/2015

LEWKALB SERIES

The Lewkalb series consists of deep, well drained soils that formed in sedimentary and granitic alluvium. Lewkalb soils are on low terraces and have slopes of 0 to 5 percent. The mean annual precipitation is about 7 inches and the mean annual temperature is about 64 degrees F.

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, calcareous, thermic Duric Torriorthents

TYPICAL PEDON: Lewkalb sandy loam - on a slope of less than 1 percent in rangeland at an elevation of 840 feet. Common plants are red brome, Russian thistle, turkey mullein, and filaree. (Colors are for dry soil unless otherwise stated. When described on 11/7/78 the soil was dry throughout the profile.)

A11--0 to 2 inches; light brownish gray (10YR 6/2) sandy loam, dark grayish brown (10YR 4/2) moist; weak thick platy structure; slightly hard, very friable, nonsticky and nonplastic; many very fine roots; common very fine tubular and interstitial pores; about 5 percent pebbles; slightly effervescent, disseminated lime; moderately alkaline (pH 8.2); abrupt smooth boundary. (1 to 2 inches thick)

A12--2 to 23 inches; pale brown (10YR 6/3) sandy loam, brown (10YR 4/3) moist; massive; soft, very friable, nonsticky and nonplastic; common very fine roots; few very fine tubular and many very fine interstitial pores; about 5 percent pebbles; violently effervescent, disseminated lime; moderately alkaline (pH 8.3); abrupt wavy boundary. (9 to 24 inches thick)

C1casi--23 to 40 inches; light gray (2.5Y 7/2) sandy loam, light brownish gray (2.5Y 6/2) moist; white (10YR 8/1) lime coating on peds, light gray (10YR 7/1) moist; strong medium and coarse angular blocky structure; hard, firm, nonsticky and nonplastic; few very fine roots; few very fine tubular and interstitial pores; about 5 percent pebbles; common thin clay films as bridges; brittle and weakly cemented with silica; violently effervescent, lime disseminated and segregated as many fine seams and filaments; strongly alkaline (pH 8.9); gradual wavy boundary. (6 to 25 inches thick)

C2casi--40 to 65 inches; light gray (2.5Y 7/2) loamy sand, light brownish gray (2.5Y 6/2) moist; moderate medium and coarse angular blocky structure; hard, firm, nonsticky; few very fine roots; few very fine interstitial and tubular pores; about 5 percent pebbles; few thin clay films as bridges; brittle and weakly cemented with silica; violently effervescent, lime disseminated and segregated as a few fine seams; slightly alkaline (pH 7.8).

TYPE LOCATION: Kern County, California; about 3 miles west-southwest of Blackwells corner, 1/4 mile east of intersection and 30 feet north of dirt road in the southeast 1/4, southwest 1/4, southwest 1/4 of section 10, T. 27 S., R. 19 E.

RANGE IN CHARACTERISTICS: Depth to the firm brittle layer is 10 to 26 inches and the thickness ranges from 12 to 42 inches. Gravel content throughout the profile is to 15 percent. Pebbles range from 2mm to 20mm in diameter. Mean annual soil temperature is 66 degrees to 68 degrees F. The soil between the depths of 8 and 25 inches is dry all the time from April 1 to December 1 and is moist in some part for less than 90 consecutive days. Organic matter content is less than 0.5 percent. The particle-size class control section averages 6 to 18 percent clay.

The A horizon has dry color of 10YR 5/3, 6/2, or 6/3 and moist color of 10YR 4/2, 4/3, 4/4, 5/3, or 5/4. It is sandy loam or loam. Structure ranges from weak platy in the surface to weak subangular blocky below the surface or are structureless. EC is greater than 2.

The C horizon has dry color of 2.5Y 7/2, 7/3, 10YR 6/4, 7/3, or 7/4 and moist color of 2.5Y 6/2, 6/3, 10YR 5/4, or 6/4. The firm brittle layer crushes to a sandy loam, loam, or loamy sand. Peds do not slake in 1N HCL. This firm layer is weakly cemented with silica. Some pedons lack thin clay films that coat sand grains. Textures below the firm layer are sandy loam or loam. The C horizon is nonsaline to moderately saline and is sometimes alkali. The SAR is 0 to 30. Some areas of this soil are underlain by a buried sandy loam or loam B horizon.

COMPETING SERIES: These are the Bubus, Domez, and Valmy series in other families. Bubus and Valmy soils are mesic. Domez soils are fine-loamy and mesic.

GEOGRAPHIC SETTING: Lewkalb soils are on low terraces with slopes of less than 5 percent. The soils formed in alluvium from sedimentary and granitic rock. Elevations are 300 to 1,000 feet. The climate is hot and dry in the summer with cool, somewhat moist winters. Mean annual rainfall is 6 to 8 inches. Mean January temperature is 46 degrees F., mean July temperature is 85 degrees F. Mean annual temperature is 64 degrees to 66 degrees F. Frost-free season is 250 to 300 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Kimberlina, Milham, and Panoche soils. Kimberlina soils lack a brittle weakly silica cemented horizon. Milham soils have an argillic horizon. Panoche soils are fine-loamy and lack a firm, brittle weakly silica cemented horizon.

DRAINAGE AND PERMEABILITY: Well drained; very slow or slow runoff; permeability is moderate or moderately rapid in the surface horizons and slow in the underlying silica cemented horizons.

USE AND VEGETATION: Used mainly for range. When water is available, irrigated crops such as cotton, alfalfa, sugar beets, potatoes, and carrots are grown. Vegetation is mainly red brome, foxtail fescue, and filaree and is within the California prairie vegetation type in the Kuchler map.

DISTRIBUTION AND EXTENT: West and east sides of the southern San Joaquin Valley of California. The soil is not extensive.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: PHOENIX, ARIZONA

SERIES ESTABLISHED: Kern County, Northwestern Part, California, 1982.

REMARKS: The classification was updated in February 2001 using the Eighth Edition to Soil Taxonomy. This series was formerly classified as coarse-loamy, mixed, calcareous, thermic Duric Torriorthents. Competing series were not checked at that time.

Responsibility for this series was transferred from Davis to Phoenix 9/2015. The last revision to the series was 3/2001. ET

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National Cooperative Soil Survey
U.S.A.