LOCATION HARDSHOULDER            CA

Established Series
Rev. EWB-JBF-TM
03/2017

HARDSHOULDER SERIES

The Hardshoulder series consists of very deep, well drained soils that formed in colluvium and residuum derived from volcanic rocks such as andesite, with additions of eolian volcanic ash. Hardshoulder soils are on mountains. Slopes are 4 to 30 percent. The mean annual precipitation is about 430 mm and the mean annual temperature is about 6 degrees C.

TAXONOMIC CLASS: Ashy-skeletal, glassy Vitrandic Argicryolls

TYPICAL PEDON: Hardshoulder very gravelly ashy sandy loam--Rangeland. (Colors are for dry soil unless otherwise noted.) The soil surface is covered with 35 percent gravel, 5 percent cobbles, 3 percent stones and 5 percent boulders.

A--0 to 5 cm; grayish brown (10YR 5/2), very gravelly ashy sandy loam, very dark grayish brown (10YR 3/2), moist; weak fine and medium subangular blocky structure; very friable, soft, nonsticky and nonplastic; common fine roots and many very fine roots; many very fine interstitial pores; 50 percent subangular gravel, 5 percent subangular cobbles; slightly acid, (pH 6.4); clear smooth boundary. (5 to 13 cm thick)

Bt1--5 to 15 cm; brown (10YR 5/3), very cobbly ashy sandy loam, dark brown (10YR 3/3), moist; weak fine and medium subangular blocky structure; very friable, soft, slightly sticky and nonplastic; many very fine roots; common very fine interstitial and tubular pores; 5 percent faint clay bridges between sand grains; 25 percent subangular gravel, 25 percent subangular cobbles; neutral (pH 6.6); clear wavy boundary. (8 to 20 cm thick)

Bt2--15 to 46 cm; brown (10YR 5/3), extremely cobbly ashy sandy loam, dark brown (10YR 3/3), moist; moderate fine and medium subangular blocky structure; very friable, slightly hard, slightly sticky and nonplastic; common very fine to medium roots; common very fine tubular and interstitial pores; 5 percent faint clay bridges between sand grains; 50 percent subangular gravel, 30 percent subangular cobbles, 5 percent subangular stones; neutral (pH 6.8); clear wavy boundary. (20 to 36 cm thick)

Btk1--46 to 61 cm; yellowish brown (10YR 5/4), extremely cobbly ashy sandy loam, dark yellowish brown (10YR 3/4), moist; weak fine and medium subangular blocky structure; very friable, slightly hard, nonsticky and nonplastic; few fine roots and common very fine roots; few fine tubular and common very fine interstitial pores; 5 percent faint clay bridges between sand grains; 25 percent fine carbonate concretions on bottom of rock fragments; 50 percent subangular gravel, 30 percent subangular cobbles, 5 percent subangular stones; neutral (pH 6.7); clear wavy boundary. (10 to 25 cm thick)

Btk2--61 to 84 cm; pale brown (10YR 6/3), extremely cobbly ashy sandy loam, brown (10YR 4/3), moist; weak fine and medium subangular blocky structure; very friable, soft, nonsticky and nonplastic; few fine roots and common very fine roots; few fine tubular and common very fine interstitial pores; 5 percent faint clay bridges between sand grains; 25 percent fine carbonate concretions on bottom of rock fragments; 50 percent subangular gravel, 30 percent subangular cobbles, 5 percent subangular stones; neutral (pH 6.8); clear wavy boundary. (0 to 38 cm thick)

Bkq1--84 to 97 cm; light brownish gray (10YR 6/2), extremely cobbly ashy coarse sandy loam, brown (10YR 4/3), moist; massive; very friable, soft, nonsticky and nonplastic; few very fine roots; common very fine and fine interstitial pores; 20 percent moderately cemented silica concretions; 25 percent fine carbonate concretions on bottom of rock fragments; 50 percent subangular gravel, 30 percent subangular cobbles, 5 percent subangular stones; neutral (pH 6.8); clear wavy boundary. (0 to 25 cm thick)

Bkq2--97 to 152 cm; light brownish gray (10YR 6/2), extremely cobbly ashy coarse sandy loam, brown (10YR 4/3), moist; massive; extremely firm, very hard, nonsticky and nonplastic; few very fine roots; common very fine interstitial pores; 10 percent faint silt coats between sand grains; 40 percent moderately cemented silica concretions; 25 percent fine carbonate concretions on bottom of rock fragments; 50 percent subangular gravel, 30 percent subangular cobbles, 5 percent subangular stones; neutral (pH 7.3).

TYPE LOCATION: Mono County, California; in the Bodie Hills about 1.8 miles northeast of the town of Bodie; about 200 feet north and 1,800 feet east of the southwest corner of section 33, T. 5 N., R. 27 E.; Bodie USGS 7.5 minute topographic quadrangle; latitude 38 degrees 14 minutes 33.4 seconds N and longitude 119 degrees 00 minutes 26.7 seconds W; WGS84 Decimal Degrees 38.2426111 latitude, -119.0074167 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist in the moisture control section; moist fall, winter and spring; usually dry July through early October; xeric moisture regime, bordering on aridic.
Mean annual soil temperature: 7 to 8 degrees C.
Mean summer soil temperature: 12 to 15 degrees C.
Mollic epipedon thickness: 40 to 60 cm.
Depth to secondary silica: 60 to 100 cm.
Depth to seondary calcium carbonate: 40 to 60 cm.
Depth to bedrock: 150 to 200 cm to a paralithic contact. The paralithic materials below the contact are weathered andesitic rock.

Particle-size control section - Clay content: Averages 12 to 18 percent.
Rock fragments: Averages 60 to 85 percent, mainly cobbles. Lithology of rock fragments is volcanic rock such as andesite.

A horizon
Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 2 or 3 dry or moist.
Reaction: Slightly acid or neutral.
Organic matter content: 2 to 4 percent.
Volcanic glass content: 30 to 75 percent in coarse silt through fine sand fractions.

Bt Horizons
Chroma: 2 or 3 dry or moist.
Texture: Extremely cobbly ashy sandy loam or very cobbly ashy sandy loam.
Clay content: Averages 12 to 18 percent.
Rock fragments: Averages 60 to 85 percent.
Reaction: Slightly acid or neutral.
Organic matter content: 1 to 3 percent.
Volcanic glass content: 30 to 75 percent in coarse silt through fine sand fractions.

Btk Horizons
Chroma: 2, 3 or 4 dry or moist.
Texture: Extremely cobbly ashy sandy loam.
Clay content: Averages 12 to 18 percent.
Rock fragments: 60 to 85 percent.
Calcium carbonate equivalent: 1 to 2 percent.
Effervescence: Noneffervescent or slightly effervescent in the matrix.
Identifiable secondary carbonates: Few to common, fine to coarse coats on undersides of rock fragments.
Calcium carbonate equivalent: 0 to 2 percent.
Reaction: Neutral or slightly alkaline.
Organic matter content: 0.5 to 1 percent.
Volcanic glass content: 30 to 75 percent in coarse silt through fine sand fractions.

Bqk Horizons
Chroma: 2, 3 or 4 dry or moist.
Texture: Extremely cobbly ashy coarse sandy loam.
Clay content: Averages 10 to 18 percent.
Rock fragments: 60 to 85 percent.
Calcium carbonate equivalent: 1 to 2 percent.
Effervescence: Noneffervescent or slightly effervescent in the matrix.
Identifiable secondary carbonates: Common to many, fine to coarse coats on undersides of rock fragments.
Calcium carbonate equivalent: 0 to 2 percent.
Reaction: Neutral or slightly alkaline.
Organic matter content: 0.5 to 1 percent.
Secondary silica: 20 to 70 percent strongly to moderately silica cemented concretions.
Volcanic glass content: 30 to 75 percent in coarse silt through fine sand fractions.

COMPETING SERIES: These are the Ashflat, Beechcreek, Boulderfan, Cowbell, Euell, Fendersflat, Paynepeak, Pyropatti, Snag and Tusune series.

Ashflat, Beechcreek Boulderfan, Cowbell, Euell, Fendersflat, Paynepeak, Pyropatti, Snag and Tusune soils lack secondary accumulation of silica. In addition, Ashflat, Beechcreek, Boulderfan, Cowbell, Fendersflat, Paynepeak, Pyropatti, Snag and Tusune soils have more than 18 percent clay in their particle-size control section. Euell soils have bedrock at 100 to 152 cm.

GEOGRAPHIC SETTING: Hardshoulder soils are on mountains. They typically occur on shoulder positions. They formed in colluvium and residuum derived from volcanic rocks such as andesite, with additions of eolian volcanic ash. Slopes are 4 to 30 percent. Elevations range from 2,505 to 3,245 meters. The climate is semi-arid with cool, moist winters and warm, dry summers. The mean annual precipitation is 400 to 500 mm, mean annual temperature is 6 to 7 degrees F., and the frost-free period is 30 to 60 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Atastra, competing Lastsummer and Roughridge series. Atastra soils have less than 35 percent rock fragment in their particle-size control section. Roughridge soils have an aridic soil moisture regime and have a frigid soil temperature regime.

DRAINAGE AND PERMEABILITY: Well drained; medium surface runoff; moderately rapid permeability; high saturated hydraulic conductivity.

USE AND VEGETATION: Hardshoulder soils are used for livestock grazing, recreation, watershed and wildlife habitat. The native vegetation is mainly mountain big sagebrush, gilia, buckwheat, pine needlegrass, prairie junegrass and Indian ricegrass.

DISTRIBUTION AND EXTENT: Eastern California, east of the Sierra Nevada Range. These soils are not extensive. MLRA 26.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California.

SERIES ESTABLISHED: Mono County (Coleville-Bridgeport Area), California, 2010.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 46 cm (A, Bt1 and Bt2 horizons).
Argillic horizon - The zone from 5 to 84 cm (Bt1, Bt2, Btk1 and Btk2 horizons).
Vitrandic intergrade feature -- High volcanic glass content in the .02 to 2mm fraction from the mineral soil surface to 152 cm (A, Bt1, Bt2, Btk1, Btk2, Bkq1 and Bkq2 horizons).
Particle-size control section - The zone from 5 to 55 cm (Bt1, Bt2 and upper Btk horizons).

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National Cooperative Soil Survey
U.S.A.