LOCATION ROADSIDE                CA

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

ROADSIDE SERIES

The Roadside series consists of shallow, well drained soils that formed in residuum and colluvium derived from volcanic rocks with surficial additions of eolian volcanic ash. Roadside soils are on hills and mountains. Slopes are 8 to 75 percent. The mean annual precipitation is about 356 mm and the mean annual temperature is about 6 degrees C.

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

TYPICAL PEDON: Roadside very gravelly ashy loamy sand--rangeland. (Colors are for dry soil unless otherwise noted.) The soil surface is covered with 40 percent gravel, 25 percent cobbles, 10 percent stones, and 2 percent boulders.

A--0 to 8 cm; grayish brown (10YR 5/2) very gravelly ashy loamy sand, very dark grayish brown (10YR 3/2) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; few very fine roots; few very fine interstitial pores; 10 percent subangular cobbles and 45 percent subangular gravel; slightly acid (pH 6.3); clear wavy boundary. (5 to 15 cm thick)

Bt1--8 to 23 cm; brown (10YR 5/3) very gravelly ashy sandy loam, dark brown (10YR 3/3) moist; weak fine and medium subangular blocky structure; soft, very friable, slightly sticky and nonplastic; common very fine to medium roots; few very fine and fine interstitial pores; 5 percent faint clay bridges between sand grains; 5 percent subangular cobbles and 40 percent subangular gravel; slightly acid (pH 6.5); clear wavy boundary. (10 to 23 cm thick)

Bt2--23 to 30 cm; pale brown (10YR 6/3) very gravelly ashy sandy loam, brown (10YR 4/3) moist; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few fine and medium roots; common fine interstitial pores; 5 percent faint clay bridges between sand grains and 5 percent faint clay films lining pores; 2 percent subangular cobbles and 50 percent subangular gravel; neutral (pH 6.7); clear wavy boundary. (5 to 15 cm thick)

Bt3--30 to 46 cm; pale brown (10YR 6/3) very gravelly ashy sandy loam, brown (10YR 4/3) moist; massive; hard, friable, slightly sticky and nonplastic; few very fine and fine roots; common very fine interstitial pores; 5 percent faint clay films lining pores and 5 percent faint clay bridges between sand grains; 45 percent subangular gravel; neutral (pH 6.7); abrupt wavy boundary. (0 to 25 cm thick)

Cr--46 to 53 cm; weathered andesite bedrock.

TYPE LOCATION: Mono County, California; in the Bodie Hills about 2.8 kilometers east of Dog Town; in a nonsectionized township; T. 4 N., R 25 E.; USGS Big Alkali 7.5 minute topographic quadrangle; latitude 38 degrees 10 minutes 24.9 seconds N and longitude 119 degrees 10 minutes 7.2 seconds W; WGS84 Decimal Degrees 38.1735833 latitude, -119.1686667 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist in the moisture control section during winter and spring; usually dry from July through early October; aridic moisture regime that borders on xeric.
Mean annual soil temperature: 7 to 8 degrees C.
Mollic epipedon thickness: 18 to 36 cm; includes the Bt1 horizon and may include the Bt2 horizon in some pedons.
Depth to bedrock: 36 to 50 cm to a paralithic contact. The paralithic materials below the contact are weathered andesitic rock. Hard, unweathered bedrock is typically within 76 cm of the soil surface.

Particle-size control section - Clay content: Averages 12 to 18 percent.
Rock fragments: Averages 35 to 60 percent, mainly gravel and cobbles. Lithology of rock fragments is volcanic rock such as andesite or andesitic tuff.

A horizon
Chroma: 2 or 3, dry or moist.
Organic matter content: 1 to 3 percent.
Reaction: Slightly acid or neutral.
Volcanic glass content: 40 to 70 percent in coarse silt through fine sand fractions.

Bt1 and Bt2 horizons
Hue: 10YR or 7.5YR.
Value: 5 dry in Bt1 horizon, 5 or 6 dry in Bt2 horizon; 3 moist in Bt1 horizon, 3 or 4 moist in the Bt2 horizon.
Chroma: 2 or 3, dry or moist.
Texture: Very gravelly ashy sandy loam or very gravelly ashy loam.
Clay content: 12 to 18 percent.
Rock fragments: 35 to 60 percent.
Organic matter content: 1 to 3 percent; may be less than 1 percent in the Bt2 horizon in some pedons.
Reaction: Slightly acid or neutral.
Volcanic glass content: 30 to 70 percent in coarse silt through fine sand fractions.

Bt3 horizon
Hue: 10YR or 7.5YR.
Chroma: 2 or 3, dry or moist.
Texture: Very gravelly ashy sandy loam or very gravelly ashy loam.
Clay content: 12 to 18 percent.
Rock fragments: 35 to 60 percent.
Organic matter content: 0.5 to 1 percent.
Reaction: Slightly acid or neutral.
Volcanic glass content: 30 to 50 percent in the very fine sand and fine sand fractions.

COMPETING SERIES: These are the Halfash and Harskel series. Both of these soils have more than 18 percent clay in the particle-size control section. In addition, Harskel soils have mollic epipedons more than 36 cm thick.

GEOGRAPHIC SETTING: Roadside soils are on hills and mountains. They typically occur on backslope positions. They formed in residuum and colluvium derived from volcanic rocks such as andesite or andesitic tuff with surficial additions of eolian volcanic ash. The probable sources of the volcanic ash are the Mono Craters and Long Valley Caldera in eastern California. Slopes are 30 to 50 percent. Elevations range from 2,000 to 2,700 meters. The climate is semiarid with cold, moist winters and warm, dry summers. The mean annual precipitation is 350 to 400 mm, the mean annual temperature is 6 to 8 degrees C., and the frost-free period is 40 to 70 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Domehill and Epvip soils and the competing Halfash soil. Domehill soils have lithic contacts within 36 cm of the soil surface and have more than 18 percent clay in the particle-size control section. Epvip soils have a xeric moisture regime and have more than 18 percent clay in the particle-size control section.

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

USE AND VEGETATION: Roadside soils are used for livestock grazing, recreation, watershed, and wildlife habitat. The native vegetation is mainly mountain big sagebrush, antelope bitterbrush, Thurber's needlegrass, Indian ricegrass with scattered singleleaf pinyon and Utah juniper.

DISTRIBUTION AND EXTENT: Eastern California, in the western part of the Great Basin. 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 23 cm (A and Bt1 horizons).
Argillic horizon - The zone from 8 to 46 cm (Bt1, Bt2, and Bt3 horizons).
Vitrandic intergrade feature - The zone from the soil surface to 46 cm (A, Bt1, Bt2, and Bt3 horizons).
Paralithic contact - The boundary at 46 cm to underlying weathered bedrock (Cr layer).
Particle-size control section and ashy-skeletal substitute class with glassy mineralogy - The zone from 8 to 46 cm (Bt1, Bt2, and Bt3 horizons).

ADDITIONAL DATA: User Pedon ID: 2006CA051030.

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National Cooperative Soil Survey
U.S.A.