LOCATION OWLSHEAD                CA

Established Series
REV: LJL/PBF/ET
12/2015

OWLSHEAD SERIES

The Owlshead series consists of very shallow and shallow to a duripan, well drained soils that formed in mixed alluvium. The Owlshead soils are on fan remnants. Slope ranges from 2 to 50 percent. The mean annual precipitation is about 5 inches and the mean annual air temperature is about 66 degrees F.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, thermic, shallow Cambidic Haplodurids

TYPICAL PEDON: On Owlshead extremely gravelly sandy loam, 2 to 8 percent slopes at an elevation of about 3,010 feet. (Colors are for dry soil unless otherwise noted.) The surface is covered by approximately 75 percent gravel, 5 percent cobbles, and a trace of stones.

A -- 0 to 2 inches; pale brown (10YR 6/3), extremely gravelly sandy loam, yellowish brown (10YR 5/4) moist; strong very thick platy structure; moderately hard, very friable, slightly sticky and nonplastic; common very fine and fine roots; common very fine, few fine interstitial and vesicular pores; violently effervescent; 75 percent gravel, 5 percent cobbles, and trace of stones; moderately alkaline (pH 8.4); clear smooth boundary. (1 to 4 inches thick)

Bw -- 2 to 6 inches; very pale brown (10YR 7/3), gravelly sandy loam, yellowish brown (10YR 5/6) moist; moderate coarse subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; common very fine and fine, few medium roots; common very fine, few fine interstitial and tubular pores; strongly effervescent; 15 percent gravel; strongly alkaline (pH 8.6); clear wavy boundary. (3 to 12 inches thick)

Bkqm1 -- 6 to 11 inches; very pale brown (10YR 8/2), moderately cemented and fractured duripan, very pale brown (10YR 7/3) moist; very hard, extremely firm, brittle; common very fine, few fine and medium roots widely spaced in fractures; violently effervescent; clear wavy boundary.

Bkqm2 -- 11 to 29 inches; very pale brown (10YR 8/2) and pale brown (10YR 6/3), very weakly cemented and fractured duripan, very pale brown (10YR 7/3) and yellowish brown (10YR 5/4) moist; moderately hard, firm, brittle; few very fine and fine roots; noneffervescent to slightly effervescent; clear wavy boundary. (Combined thickness of the Bkqm horizon is 5 to 25 inches.)

C1 -- 29 to 50 inches; gray (10YR 6/1), gravelly sand, yellowish brown (10YR 5/4) moist; massive; soft, very friable, nonsticky and nonplastic; common very fine and few fine roots; noneffervescent; 25 percent gravel; slightly alkaline (pH 7.8); gradual wavy boundary.

C2 -- 50 to 65 inches; gray (10YR 6/1), very gravelly coarse sand, yellowish brown (10YR 5/4) moist; massive; soft, very friable, nonsticky and nonplastic; noneffervescent; 45 percent gravel; slightly alkaline (pH 7.8).

TYPE LOCATION: San Bernardino County, California; about 50 feet east and 2,050 feet north of the SW corner of proposed sec. 9, T. 14 N., R. 3 E.; 35 degrees, 19 minutes, 16 seconds north latitude, and 116 degrees, 40 minutes, 36 seconds west longitude; Fort Irwin 7.5 minute quadrangle; UTM 11S, 0529397e 3908510n (DTM:NAS-C).

RANGE IN CHARACTERISTICS:

Soil moisture control section - 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: 63 to 72 degrees F.

Organic matter: 0 to 0.5 percent

Surface rock fragments: 50 to 85 percent gravel, 0 to 35 percent cobbles, and 0 to 15 percent stones

Control section -

Rock fragments: 35 to 85 percent

Depth to duripan: 4 to 14 inches

A horizon

Value: 4 or 5 moist

Chroma: 2 to 4 dry, 3 or 4 moist

Texture of the fine earth: sandy loam or loam

Reaction: moderately or strongly alkaline

Clay content: 8 to 18 percent

Rock fragments: 60 to 85 percent; with 35 to 75 percent
gravel, 5 to 35 percent cobbles, and 0 to 2 percent
stones

Salinity: 0 to 4 dS/m

Sodium adsorption ratio: 0 to 5

Bw horizon

Value: 6 or 7 dry, 4 or 5 moist

Chroma: 3 or 4 dry, 4 to 6 moist

Texture of the fine earth: sandy loam or loam

Clay content: 8 to 18 percent

Structure: platy or subangular blocky

Reaction: moderately or strongly alkaline

Salinity: 0 to 4 dS/m

Sodium adsorption ratio: 0 to 5

Rock fragments: 15 to 50 percent; with 15 to 30 percent
gravel, 0 to 15 percent cobbles, and 0 to 2 percent
stones

Bkqm horizon

Value: 6 to 8 moist

Chroma: 1 or 2 dry, 3 to 6 moist

Cementation: very weakly to strongly cemented

Bk horizon (when present)

Hue: 10YR or 7.5YR

Value: 7 or 8 dry, 4 or 6 moist

Chroma: 2 or 3 dry and moist

Texture of the fine earth: coarse sand or loamy sand

Clay content: 2 to 6 percent

Reaction: moderately or strongly alkaline

Salinity: 2 to 8 dS/m

Sodium adsorption ratio: 5 to 12

Rock fragments: 30 to 55 percent gravel, 0 to 15 percent
cobbles, and 0 to 5 percent stones

Calcium carbonate equivalence: 5 to 10 percent

Carbonates: 0 to 20 percent by volume


C horizon

Value: 6 or 7 dry, 4 or 5 moist

Chroma: 1 to 3 dry

Texture of the fine earth: sand, coarse sand, or loamy
sand

Clay content: 2 to 6 percent

Rock fragments: 25 to 70 percent; with 25 to 60 percent
gravel, 0 to 25 percent cobbles, and 0 to 5 percent
stones

Effervescence: noneffervescent to violently effervescent

Reaction: slightly or moderately alkaline

Carbonates: 0 to 20 percent by volume

Durinodes: 0 to 10 percent

Salinity: 0 to 8 dS/m

Sodium adsorption ratio: 0 to 12

COMPETING SERIES: These are the Puelzmine (T NV) and Ustidur (T NV) series. Puelzmine is deeper to a duripan and the duripan overlies bedrock. Ustidur soils have a moisture regime bordering on ustic. Similar soils in a Typic subgroup include the Crosgrain (T NV), Greyeagle (CA), Longjim (NV), and Tumarion (T AZ) series. These soils all have an indurated duripan.

GEOGRAPHIC SETTING: Owlshead soils are on fan remnants. Slopes are 2 to 50 percent. These soils formed in mixed alluvium. Elevations are 1,950 to 3,500 feet. The climate is arid with hot, dry summers and warm, moist winters. The mean annual precipitation is 2 to 7 inches; mean annual air temperature is 61 to 70 degrees F., and the frost-free season is 240 to 340 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Arizo, Crackerjack (T), and Tenwell soils. Arizo soils do not have a duripan, have a sandy-skeletal particle-size control section and are found in inset fans and alluvial fans. Crackerjack soils are on ballenas and similar fan remnants and have a loamy particle-size control section. Tenwell soils are on remnants on lower slopes of ballenas and have fine-loamy particle-size control sections and a duripan below 20 inches.

DRAINAGE AND PERMEABILITY: Well drained; very high to medium runoff; moderately rapid permeability above the duripan.

USE AND VEGETATION: Owlshead soils are used for military exercises and wildlife habitat. The present vegetation is mainly shadscale, creosotebush and white bursage.

DISTRIBUTION AND EXTENT: Mojave Desert of southeastern California. MLRA 30. These soils are of small extent.

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

SERIES ESTABLISHED: San Bernardino County, California, Fort Irwin Soil Survey Area, 2000. The name is from the Owlshead Mountains to the north of the survey area.

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

1. Ochric epipedon -- 0 to 2 inches (A horizon).
2. Duripan -- 6 to 29 inches (Bkqm1 and Bkqm2 horizons).
3. Particle size control section -- 0 to 6 inches (A and Bw
horizons).

Responsibility for this series was transferred from Davis to Phoenix 12/2015. The last revision to the series was 6/2000. ET

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National Cooperative Soil Survey
U.S.A.