LOCATION ROUGHRIDGE              CA

Established Series
Rev. EWB-JBF-TM
06/2017

ROUGHRIDGE SERIES

The Roughridge series consists of very deep, well drained soils that formed in colluvium derived from volcanic rocks such as andesite with additions of eolian volcanic ash. Roughridge soils are on mountains. Slopes are 15 to 50 percent. The mean annual precipitation is about 430 mm and the mean annual temperature is about 6 degrees C.

TAXONOMIC CLASS: Ashy-skeletal, glassy, frigid Vitritorrandic Argixerolls

TYPICAL PEDON: Roughridge extremely cobbly ashy sandy loam--Rangeland. (Colors are for dry soil unless otherwise noted.) The soil surface is covered with 50 percent gravel, 15 percent cobbles, 10 percent stones and 3 percent boulders.

A--0 to 10 cm; grayish brown (10YR 5/2) extremely cobbly ashy sandy loam, very dark grayish brown (10YR 3/2) moist; weak fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine roots; many very fine interstitial pores; 2 percent subangular andesite stones, 10 percent flat angular andesite flagstones, 25 percent subangular andesite cobbles and 45 percent subangular andesite gravel; neutral (pH 7.2); clear wavy boundary. (5 to 15 cm thick)

Bt1--10 to 28 cm; brown (10YR 5/3) extremely cobbly ashy sandy loam, dark brown (10YR 3/3) moist; weak fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine and fine roots and common medium and coarse roots; many very fine interstitial pores; 5 percent faint clay bridges between sand grains; 2 percent subangular andesite stones, 10 percent flat angular andesite flagstones, 25 percent subangular andesite cobbles and 45 percent subangular andesite gravel; neutral (pH 7.2); clear wavy boundary. (13 to 28 cm thick)

Bt2--28 to 48 cm; pale brown (10YR 6/3) extremely cobbly ashy sandy loam, brown (10YR 4/3) moist; moderate medium subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; many very fine and fine roots and common medium and coarse roots; common fine tubular and many very fine interstitial pores; 5 percent faint clay bridges between sand grains; 2 percent subangular andesite stones, 10 percent flat angular andesite flagstones, 25 percent subangular andesite cobbles and 45 percent subangular andesite gravel; neutral (pH 7.2); clear wavy boundary. (15 to 30 cm thick)

Bkq1--48 to 81 cm; pale brown (10YR 6/3) extremely cobbly ashy coarse sandy loam, brown (10YR 4/3) moist; weak medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine to medium roots; fine silica concretions on bottom of rock fragments and fine carbonate concretions on bottom of rock fragments; 2 percent subangular andesite stones, 10 percent flat angular andesite flagstones, 25 percent subangular andesite cobbles and 50 percent subangular andesite gravel; neutral (pH 7.3); clear wavy boundary. (23 to 43 cm thick)

Bkq2--81 to 150 cm; pale brown (10YR 6/3) extremely cobbly ashy coarse sandy loam, brown (10YR 4/3) moist; massive; soft, very friable, nonsticky and nonplastic; common very fine and fine roots; fine carbonate concretions on bottom of rock fragments and fine silica concretions on bottom of rock fragments; 2 percent subangular andesite stones, 10 percent flat angular andesite flagstones, 25 percent subangular andesite cobbles and 45 percent subangular andesite gravel; moderately alkaline (pH 8.4);

TYPE LOCATION: Mono County, California; in the Bodie Hills about 1.6 miles southwest of Potato Peak; about 300 feet south and 2,300 feet east of the northwest corner of section 1, T. 4 N., R. 26 E.; Bodie USGS 7.5 minute topographic quadrangle; latitude 38 degrees 14 minutes 28.5 seconds N and longitude 119 degrees 03 minutes 31.5 seconds W; WGS84 Decimal Degrees 38.2412500 latitude, -119.0587500 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually dry in the moisture control section; moist fall, winter and early spring; usually dry July through early October; aridic moisture regime bordering on xeric.
Mean annual soil temperature: 7 to 8 degrees C.
Mean summer soil temperature: 15 to 19 degrees C.
Mean winter soil temperature: 0 to 2 degrees C.
Mollic epipedon thickness: 25 to 41 cm, includes the Bt1 horizon, and may include the Bt2 horizon in some pedons.
Depth to secondary silica cementation: 41 to 61 cm.
Depth to secondary calcium carbonate: 41 to 61 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: 1 to 3 percent.
Volcanic glass content: 30 to 75 percent in coarse silt through fine sand fractions.

Bt Horizons
Value: 5 dry in upper part, 5 or 6 dry in lower part, 3 moist in upper part, 3 or 4 moist in lower part.
Chroma: 2 or 3 dry or moist.
Texture: 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: 0 to 2 percent in matrix.
Volcanic glass content: 30 to 75 percent in coarse silt through fine sand fractions.

Bkq Horizons
Chroma: 2, 3 or 4 dry or moist.
Texture: 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: Few to common, fine to coarse coats on undersides of rock fragments.
Calcium carbonate equivalent: 0 to 2 percent.
Reaction: Neutral, slightly alkaline or moderately alkaline.
Organic matter content: 0.5 to 1 percent.
Secondary silica: Few to common, fine to coarse coats on undersides of rock fragments.
Volcanic glass content: 30 to 75 percent in coarse silt through fine sand fractions.

COMPETING SERIES: These are the Cabinspring, Cagas, Derallo, Glassbutte, Jacksplace and Slockey soils.

Cabinspring, Cagas, Derallo, Jacksplace and Slockey soils have bedrock within 150 cm. Glassbutte soils lack accumulations of secondary silica. In addition, all of these soils have more than 18 percent clay in their particle-size control section.

GEOGRAPHIC SETTING: Roughridge soils are on mountains. They typically occur on convex crest, shoulder and backslope positions. The majority of the precipitation occurs as snow, much of which is removed from the surface of the soil through wind action. This removal of snow greatly reduces the effective precipitation on this soil relative to surrounding non-convex areas. They formed in colluvium derived from volcanic rocks such as andesite, with additions of eolian volcanic ash. Slopes are 15 to 50 percent. Elevations range from 2,445 to 3,115 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 C., and the frost-free period is 30 to 60 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Hardshoulder and Lastsummer series. Hardshoulder and Lastsummer soils have xeric soil moisture regimes, cryic soil temperature regimes and have mollic epipedons greater than 41 cm thick.

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

USE AND VEGETATION: Roughridge soils are used for livestock grazing, recreation, watershed, and wildlife habitat. The native vegetation is mainly low sagebrush, buckwheat, pine needlegrass, prairie junegrass, gilia and bluegrass.

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 28 cm (A and Bt1 horizons).
Argillic horizon - The zone from 10 to 48 cm (Bt1 and Bt2 horizons).
Vitrandic intergrade feature - High volcanic glass content in the .02 to 2mm fraction from the mineral soil surface to 150 cm (A, Bt1, Bt2, Bkq1 and Bkq2 horizons).
Particle-size control section - The zone from 10 to 48 cm (Bt1 and Bt2 horizons).

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National Cooperative Soil Survey
U.S.A.