LOCATION KENTONMILL              CA

Established Series
JCR/LJL/ET
09/2015

KENTONMILL SERIES


The Kentonmill series consists of very shallow and shallow to bedrock, somewhat excessively drained soils that formed in residuum and colluvium from basalt with eolian material influence. Kentonmill soils are on summits of lava flows and have slopes of 0 to 2 percent. The mean annual precipitation is about 4 inches and the mean annual air temperature is about 72 degrees F.

TAXONOMIC CLASS: Loamy, mixed, superactive, nonacid, hyperthermic Lithic Torriorthents

TYPICAL PEDON: Kentonmill-Lava flows complex, 0 to 2 percent slopes, at an elevation of 1900 feet. (Colors are for dry soil unless otherwise noted.) The surface is covered by approximately 70 percent gravel, 15 percent cobbles and trace of stones.

A--0 to 2 inches; light gray (10YR 7/2) extremely gravelly fine sandy loam, brown (10YR 4/3) moist; moderate thick platy structure; slightly hard, very friable, nonsticky and nonplastic; common very fine and fine vesicular pores; electrical conductivity 1 dS/m; sodium adsorption ratio 11; 60 percent gravel, 15 percent cobbles and trace of stones; noneffervescent to very slightly effervescent (4 percent calcium carbonate equivalence); strongly alkaline (pH 8.8); abrupt smooth boundary. (1 to 3 inches thick).

A/Btn--2 to 4 inches; pale brown (10YR 6/3) loam, dark yellowish brown (10YR 4/4) moist; strong very thick platy structure; moderately hard, very friable, slightly sticky and slightly plastic; few very fine and fine roots; common very fine and fine vesicular pores; 75 percent continuous prominent clay films on faces of peds and pores; electrical conductivity 2 dS/m; sodium adsorption ratio 18; trace of gravel; very slightly effervescent (4 percent calcium carbonate equivalence); strongly alkaline (pH 8.6); abrupt smooth boundary. (2 to 6 inches thick).

Bkn--4 to 7 inches; light yellowish brown (10YR 6/4) loam, dark yellowish brown (10YR 4/4) moist; massive; slightly hard, very friable, slightly sticky and slightly plastic; few very fine and fine roots; common very fine and few fine interstitial and tubular pores; 10 percent disseminated pockets of lime; electrical conductivity 2 dS/m; sodium adsorption ratio 23; trace of gravel; strongly effervescent (10 percent calcium carbonate equivalence); strongly alkaline (pH 9.0); abrupt smooth boundary. (1 to 5 inches thick).

R--7 inches; hard basalt bedrock.

TYPE LOCATION: San Bernardino County, California; about 8.5 miles southwest of Ludlow, Calilifornia; 800 feet south and 400 feet west of the northeast corner of section 22 , T. 7 N., R. 6 E.; 34 degrees, 41 minutes, 16.0 seconds north latitude and 116 degrees, 19 minutes, 47.5 seconds west longitude; Lavic Lake quadrangle; UTM 11S, 0561386e 3838429n; NAS-C.

RANGE IN CHARACTERISTICS:

Soil moisture - usually dry, moist in some part for short periods during winter and early spring and for 10 to 20 days cumulative between July and October following convection storms. The soils have a Typic-Aridic moisture regime.

Soil Temperature: 72 to 77 degrees F.

Depth to bedrock: 4 to 14 inches.

Organic matter: 0 to 0.5 percent.


Particle-size control section - Rock fragments: averages 5 to 20 percent.

Clay content: 6 to 12 percent.


A horizon - Value: 6 or 7 dry.

Chroma: 2, 3 or 4 dry, 3 or 4 moist.

Rock fragments: 60 to 80 percent.

Texture: fine sandy loam and loam.

Structure: Moderate or strong, medium through very coarse.

Consistence: Soft through moderately hard.

Effervescence: Non-effervescent through strongly effervescent.

Reaction: strongly to very strongly alkaline.

Electrical conductivity: 1 to 4 dS/m.

Sodium adsorption ratio: 5 to 13.

Calcium carbonate equivalence: 0 to 5 percent.


Atn horizon - Value: 6 or 7 dry.

Chroma: 2, 3 or 4 dry, 3 or 4 moist.

Rock fragments: 0 to 10 percent.

Texture: fine sandy loam and loam.

Structure: Moderate or strong, medium through very coarse.

Consistence: Soft through moderately hard.

Effervescence: Non-effervescent through strongly effervescent.

Electrical conductivity: 1 to 4 dS/m.

Sodium adsorption ratio: 13 to 25.

Calcium carbonate equivalence: 0 to 5 percent


Bkn horizon - Texture: fine sandy loam and loam.

Rock fragments: 0 to 10 percent.

Effervescence: Strongly effervescent or violently effervescent.

Electrical conductivity: 1 to 4 dS/m.

Sodium adsorption ratio: 13 to 25.

Calcium carbonate equivalence: 5 to 15 percent.

COMPETING SERIES: There are no competing series at this time.

GEOGRAPHIC SETTING: Kentonmill soils are on summits of lava flows. Slopes are 0 to 2 percent. These soils formed residuum and colluvium from basalt with eolian material influence. Elevations are 1850 to 1950 feet. The climate is arid with hot, dry summers and warm, moist winters. The mean annual precipitation is 2 to 6 inches; mean annual air temperature is 69 to 74 degrees F., and the frost-free season is 300 to 360 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Haleburu and Sunrock soils. Haleburu and Sunrock soils have loamy-skeletal textural control sections. Haleburu soils have mean annual soil temperatures of 66 to 71 degrees F.

DRAINAGE AND PERMEABILITY: Somewhat excessively drained; negligible runoff; moderate permeability over impermeable bedrock.

USE AND VEGETATION: Kentonmill soils are used for military exercises and wildlife habitat. The present vegetation is mainly desert holly, Anderson wolfberry and white bursage.

DISTRIBUTION AND EXTENT: Mojave desert of southeastern California, U.S.A.; MLRA 30. These soils are of small extent.

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

SERIES ESTABLISHED: San Bernardino County, California, Marine Corps Air/Ground Combat Center Soil Survey Area, 2000. The name is coined from a nearby abandoned mill site.

REMARKS: Diagnostic horizons and features recognized in the profile are:

1. Ochric epipedon -- 0 to 4 inches (A and Atn horizons).
2. Particle-size control section -- 0 to 7 inches (A, Atn and Bk horizons).

Responsibility for this series was transferred from Davis to Phoenix 9/2015. The last revision to the series was 1/2002. ET


National Cooperative Soil Survey
U.S.A.