LOCATION CARUTHERS               CA

Tentative Series
SMR/LJL/ET
05/2023

CARUTHERS SERIES

The Caruthers series consists of deep to a hardpan, well drained soils that formed in alluvium derived from igneous and sedimentary rock. The Caruthers soils are on fan remnants. Slopes range from 1 to 4 percent. The mean annual precipitation is about 175 mm, and the mean annual temperature is about 16 degrees C.

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, thermic Typic Petroargids

TYPICAL PEDON: Caruthers fine sandy loam, on an east facing, 1 percent slope under rangeland at an elevation of 1145 meters. (Colors are for dry soils unless otherwise noted. 8/9/2011 actual site observation date.) The soil surface is covered by approximately 15 percent fine gravel, 5 percent medium and coarse gravel.

A--0 to 5 cm (0 to 2 inches); pale brown (10YR 6/3) fine sandy loam, brown (10YR 4/3), moist; moderate very thick platy structure; soft, very friable, slightly sticky and nonplastic; common very fine roots throughout; common very fine irregular pores; 2 percent fine gravel, 1 percent medium and coarse gravel; neutral (pH 6.8); abrupt smooth boundary.

BA--5 to 14 cm (2 to 6 inches); pale brown (10YR 6/3) sandy loam, brown (10YR 4/3), moist; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky and nonplastic; common very fine roots throughout; common very fine irregular pores; 2 percent fine gravel, 1 percent medium and coarse gravel; neutral (pH 6.9); clear smooth boundary. (The combined thickness of the A and BA horizons is 4 to 20 cm.)

Bt1--14 to 32 cm (6 to 13 inches); brown (10YR 5/3) sandy loam, brown (7.5YR 4/3), moist; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine roots throughout; common fine dendritic tubular and common very fine dendritic tubular pores; 5 percent faint brown (10YR 5/3), dry, clay bridges between sand grains; 4 percent fine gravel, 1 percent medium and coarse gravel; slightly alkaline (pH 7.4); gradual smooth boundary.

Bt2--32 to 67 cm (13 to 26 inches); brown (10YR 5/3) sandy loam, brown (7.5YR 4/3), moist; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky and moderately plastic; few very fine roots throughout; few very fine irregular and common very fine dendritic tubular pores; 20 percent faint brown (10YR 5/3), dry, clay films on surfaces along pores; 4 percent fine gravel, 1 percent medium and coarse gravel; moderately alkaline (pH 7.9); clear smooth boundary. (The combined thickness of the Bt horizons is 20 to 56 cm.)

Btk1--67 to 109 cm (26 to 43 inches); yellowish brown (10YR 5/4) sandy clay loam, brown (7.5YR 5/4), moist; moderate coarse subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; few very fine roots throughout; few very fine irregular pores; 75 percent distinct brown (7.5YR 5/4), dry, clay bridges between sand grains and 90 percent prominent very pale brown (10YR 8/2), dry, carbonate coats on rock fragments; 7 percent fine gravel, 3 percent medium and coarse gravel; slight effervescence; moderately alkaline (pH 8.4); gradual wavy boundary.

Btk2--109 to 122 cm (43 to 48 inches); pale brown (10YR 6/3) gravelly sandy loam, light yellowish brown (10YR 6/4), moist; moderate coarse subangular blocky structure; slightly hard, very friable, moderately sticky and moderately plastic; few very fine roots throughout; few very fine irregular pores; 3 percent prominent very pale brown (10YR 8/2), dry, carbonate coats on surfaces along root channels and 75 percent prominent light brown (7.5YR 6/4), dry, clay bridges between sand grains and 90 percent prominent very pale brown (10YR 8/2), dry, carbonate coats on rock fragments; 23 percent fine gravel, 7 percent medium and coarse gravel; slight effervescence; strongly alkaline (pH 8.7); abrupt wavy boundary. (The combined thickness of the Btk horizons is 20 to 71 cm.)

Bkkq--122 to 155 cm (48 to 61 inches); white (10YR 8/1) cemented sandy loam, very pale brown (10YR 7/3), moist; massive; very hard, very firm, weakly coherent by carbonates, slightly sticky and nonplastic; 20 percent faint very pale brown (10YR 8/3), dry, silica coats on concretions; 5 percent coarse faint platy strongly coherent cemented white (10YR 8/1), dry, carbonate nodules with sharp boundaries at top of horizon; 4 percent fine gravel, 1 percent medium and coarse gravel; violent effervescence (40 percent calcium carbonate equivalence in the fine earth fraction); moderately alkaline (pH 8.3).

TYPE LOCATION: San Bernardino County, California; about 14 miles north-northwest of Goffs, CA, located in the south end of Lanfair Valley; approximately 630 feet west and 1180 feet north of the southeast corner of section 15, T. 12 N., R. 17 E., San Bernardino Baseline and Meridian; USGS Hackberry Mountain, California 7.5 minute topographic quadrangle; 35 degrees, 7 minutes, 0.59 seconds north latitude and 115 degrees, 7 minutes, 45.87 seconds west longitude; UTM zone 11 670462e, 3887600n, NAD83.

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 September following summer convection storms; typic aridic moisture regime.

Soil temperature: 15 to 19 degrees C (59 to 66 degrees F).
Depth to argillic horizon: 4 to 50 centimeters (2 to 20 inches).
Depth to petrocalcic contact: 110 to 150 centimeters (43 to 60 inches).
Organic matter: 0 to 0.5 percent.

Control section
Rock fragments: averages 5 to 20 percent, ranges from 0 to 35 percent.
Clay content: averages 12 to 18 percent, ranges from 12 to 25 percent.

A horizons
Hue: 10YR or 7.5YR.
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 3 or 4 dry.
Texture of the fine earth fraction: sandy loam or fine sandy loam.
Clay content: 6 to 12 percent.
Rock fragments: 0 to 15 percent.
Reaction: neutral or slightly alkaline.

BA or Bw horizons
Value: 4 or 5 dry.
Chroma: 3 or 4 dry.
Texture of the fine earth fraction: sandy loam or fine sandy loam.
Clay content: 6 to 12 percent.
Rock fragments: 0 to 15 percent.
Reaction: slightly alkaline or moderately alkaline.

Bt horizons
Hue: 10YR or 7.5YR.
Chroma: 3 or 4 dry.
Texture of the fine earth fraction: sandy loam, and fine sandy loam.
Clay content: 12 to 18 percent.
Rock fragments: 0 to 15 percent.
Reaction: slightly alkaline or moderately alkaline.

Btk horizons
Hue: 10YR or 7.5YR.
Value: 4 to 7 dry, 4 to 6 moist.
Chroma: 3 to 6 dry.
Texture of the fine earth fraction: sandy loam or sandy clay loam.
Clay content: 15 to 25 percent.
Rock fragments: 0 to 35 percent.
Effervescence: very slight to strongly effervescent.
Reaction: moderately alkaline or strongly alkaline.

Bkq or Ck horizons (when present)
Hue: 10YR or 7.5YR.
Value: 5 to 7 dry, 5 or 6 moist.
Chroma: 3 to 6 moist.
Clay content: 3 to 12 percent.
Rock fragments: 0 to 35 percent.
Effervescence: slightly or strongly effervescent.
Reaction: slightly alkaline or moderately alkaline.

Bkkq or Bkkqm horizons
Value: 7 to 8 dry, 6 to 8 moist.
Chroma: 1 to 3 dry, 2 to 4 moist.
Clay content: 6 to 12 percent.
Rock fragments: 0 to 35 percent.
Reaction: moderately alkaline or strongly alkaline.
Calcium carbonate equivalence of the fine earth fraction: 30 to 45 percent.
Cementation: weakly to strongly cemented; 50 to 100 percent continuous.

COMPETING SERIES: This is the Rotura (NM) series. Rotura soils have a calcic horizon over an indurated petrocalcic horizon and occur on board basin floors.

GEOGRAPHIC SETTING: The Caruthers soils are on fan remnants. Slopes range from 1 to 4 percent. The soils formed in alluvium derived from igneous and sedimentary rock. Elevation ranges from 1060 to 1400 meters. The mean annual precipitation is 150 to 200 mm. The mean annual air temperature is about 15 to 18 degrees C. The frost-free period is 210 to 280 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Castaneda and Helendale series. The Castaneda and Helendale soils are on similar landforms. Castaneda soils are moderately deep to a petrocalcic horizon and have a fine-loamy particle-size control section. Helendale soils do not have a hardpan.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; low runoff; moderate saturated hydraulic conductivity.

USE AND VEGETATION: Caruthers soils are used for recreation and wildlife habitat. Native vegetation is Cooper's goldenbush, big galleta, Nevada ephedra and Joshua tree.

DISTRIBUTION AND EXTENT: Mojave Basin and Range of California, U.S.A.; MLRA 30. The series is of moderate extent.

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Phoenix, Arizona

SERIES PROPOSED: San Bernardino County, California, Soil Survey of Mojave National Preserve Area, California, 2023. The name is from Caruthers Canyon located in the survey area.

REMARKS: Diagnostic horizons and features in this pedon include:

Ochric epipedon - the zone from 0 to 18 cm. (A and BA horizons)
Argillic horizon - the zone from 14 to 122 cm. (Bt and Btk horizons)
Petrocalcic horizon - the zone from 122 to 155 cm. (Bkkq horizon)
Particle size control section - the zone from 32 to 82 cm. (Bt1 and part of the Bt2 horizons)

ADDITIONAL DATA: NASIS User Site ID: 2011CA071059.

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National Cooperative Soil Survey
U.S.A.