LOCATION ADELANTO                CA

Established Series
Rev. GAW/LCL/ET
04/2015

ADELANTO SERIES

The Adelanto series consists of very deep, well drained soils that formed in granitic parent material on alluvial fans and plains. Slopes range from 0 to 5 percent. The mean annual precipitation is about 7 inches, and the mean annual temperature is about 65 degrees F. The Adelanto soils have brown and light brown slightly acid and neutral sandy loam A horizons, reddish brown, moderately alkaline somewhat finer textured sandy loam B2t horizons and brown somewhat coarser sandy loam alluvial C horizons.

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, thermic Xeric Haplargids

TYPICAL PEDON: Adelanto coarse sandy loam - desert shrubs and annuals (Colors for dry conditions unless otherwise noted.)

A1--0 to 16 inches; brown (10YR 5/3) coarse sandy loam, dark brown (10YR 4/3) moist; massive; slightly hard, friable, nonsticky, nonplastic; plentiful micro, few very fine and fine roots; common micro interstitial, few micro and very few very fine tubular pores; slightly acid (pH 6.5); gradual wavy boundary. (6 to 17 inches thick)

AB--16 to 27 inches; light brown (7.5YR 6/4) sandy loam, dark brown (7.5YR 4/4) moist; massive; slightly hard, frible, nonsticky, nonplastic; plentiful micro, few very fine roots; common micro interstitial, few micro tubular pores; neutral (pH 7.0); gradual wavy boundary. (0 to 11 inches thick)

Btk--27 to 41 inches; light brown (7.5YR 6/4) sandy loam, dark brown (7.5YR 4/4) moist; massive slightly hard, friable, nonplastic, nonsticky; few micro and very fine roots; common micro interstitial, very few very fine tubular pores; few thin clay films as bridges; strongly effervescent lime that occurs as soft masses; moderately alkaline (pH 8.0); clear wavy boundary. (6 to 16 inches thick)

Bt1--41 to 50 inches; reddish brown (5YR 5/4) heavy sandy loam, reddish brown (5YR 4/4) moist; weak fine and medium angular blocky structure; hard, firm, slightly sticky, slightly plastic; few micro roots; few micro interstitial and very fine tubular pores; few moderately thick clay films on ped faces, common moderately thick clay films as bridges and in pores; has about 10 to 15 percent fine gravels by volume; disseminated lime slightly effervescent; moderately alkaline (pH 8.2); clear wavy boundary. (6 to 10 inches thick)

Bt2--50 to 64 inches; reddish brown (5YR 5/4) heavy sandy loam near loam, reddish brown (5YR 4/4) moist; weak fine and medium angular blocky structure; very hard, firm, slightly sticky, slightly plastic; very few micro roots; very few micro interstitial, few micro and very few very fine tubular pores; has about 14 percent by volume fine gravels; common moderately thick clay films on ped faces; few thin clay films as bridges; strongly effervescent disseminated lime; moderately alkaline (pH 8.4) clear wavy boundary. (6 to 14 inches thick)

Bt3--64 to 80 inches; brown (7.5YR 5/4) heavy sandy loam, dark brown (7.5YR 4/4) moist; massive; hard, firm, slightly sticky, slightly plastic; few micro interstitial pores; about 10 percent fine gravels by volume; few moderately thick clay films on ped faces and a few thin clay films as bridges; strongly effervescent, disseminated lime; moderately alkaline (pH 8.4); clear wavy boundary. (8 to 18 inches thick)

C--80 to 86 inches; brown (7.5YR 5/4) coarse sandy loam, dark brown (7.5YR 4/4) moist; massive; slightly hard, friable, nonsticky, nonplastic; disseminated lime slightly effervescent; moderately alkaline (pH 8.4). (Many feet.)

TYPE LOCATION: Los Angeles County, California; NE 1/4, SE 1/4, Sec. 6 T. 6 N, R. 12 W; intersection of Avenue M-8 and 37th Street West.

RANGE IN CHARACTERISTICS: Adelanto soils have ochric epipedons and argillic subsurface horizons. The solum thickness ranges from 32 to 86 inches, the great variation being due to differences in precipitation and the slow differential accretion of soil material. Coarse fragments of gravel size may range from 1 to 35 percent throughout the profile; 1 to 10 percent fine gravels are common. The soils are usually dry throughout the year. Mean soil temperature ranges from about 65 to 71 F. Mineralogy is mixed.

A hues are usually 10YR and 7.5YR and include 5YR. Chromas are 3 and 4 and may include 2; dry values are 5 and 6 and 4 moist. Organic matter content is very low. Textures of the A may be loamy sand or sandy loam; usually some coarse sand and fine gravel are noticeable. The A may be massive, or may have weak plates near the surface. Dry consistence is soft or slightly hard. Reaction may range from slightly acid to slightly alkaline except where soil manipulation or irrigation water has added lime. An A3 or AB horizon is usually present or the boundary between A and Bt is not abrupt.

Color of the Bt horizon is in hues of 7.5YR and 5YR with chromas of 3 to 6. Textures are a sandy loam, but with less than 18 percent clay and at least 3 percent more clay than the A. Structure is usually weak.

The Bt may be massive or it may have weak to moderate angular blocky or even weak priamatic structure. Dry consistence is hard. Reaction is slightly or moderately alkaline. Usually the Bt is noncalcareous at least in the upper part, but there is much variation and all or none may be calcareous. Usually the uppermost lime is in the form of segregations or soft powdery secondary lime.

The C horizons are usually somewhat stratified coarse sandy loams, and loamy sands with some gravel and sand. Reaction is moderately alkaline and usually the C is weakly calcareous. Lenses with lime segragations and thin seams of weak lime cementation are common.

COMPETING SERIES: These are the Chollawell, Cowspring and Lucerne soils. The Chollawell soils have a mean annual soil temperature of 59 to 64 degrees F. Cowspring soils are moderately deep to partially decomposed granodiorite bedrock. Lucerne soils do not have a Btk horizon and typically have an older buried Bt horizon with an upper boundary at about 60 inches.

GEOGRAPHIC SETTING: Adelanto soils occur on nearly level to gently sloping alluvial fans and plains. The sediments are derived mostly from granite and closely related rocks. The climate is arid. Annual precipitation is about 4 to 9 inches. Winters are cool with occasional gentle rains and a little snow. Summer are hot with very infrequent thunder showers. The mean air temperature is about 65 F; the average July temperature is about 82 F; the average January temperature is about 44 F. The frost-free period is about 250 to 260 days. Elevations range from 2,000 to 2,900 feet.

GEOGRAPHICALLY ASSOCIATED SOILS: Adelanto soils occur in the same general area as Cajon, Hesperia and Mohave. Cajon and Hesperia are young soils lacking argillic horizons.

DRAINAGE AND PERMEABILITY: Well drained; runoff is low to very low; permeability is moderate to moderately rapid.

USE AND VEGETATION: Large areas are used for desert range. With irrigation, alfalfa is the main crop. Native Vegetation is creosote bush, a few annual grasses and forbs, a few perennial grasses, with a little Joshua and juniper trees on the more moist fringes.

DISTRIBUTION AND EXTENT: Mohave Desert area of California and adjoining Southwest (upper desert). The series is extensive. MLRA 30

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

SERIES ESTABLISHED: Victorville Area, California 1921.

REMARKS: The Adelanto series was formerly classified in the Red Desert Group, and Xeralfic Haplargids.

Series reclassified on September, 1997. CEC activity class determined from lab data. Competing series reviewed at that time.

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National Cooperative Soil Survey
U.S.A.