LOCATION TEPHZITE                CA

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

TEPHZITE SERIES

The Tephzite series consists of very deep, well drained soils that formed in colluvium and residuum derived from metamorphic rock such as quartzite with surficial additions of eolian volcanic ash. Tephzite soils are on hills and mountains. Slopes are 4 to 30 percent. The mean annual precipitation is about 380 mm and the mean annual temperature is about 6 degrees C.

TAXONOMIC CLASS: Ashy-skeletal over loamy-skeletal, glassy over mixed, semiactive, frigid Vitrandic Argixerolls

TYPICAL PEDON: Tephzite very gravelly ashy very fine sandy loam--rangeland. (Colors are for dry soil unless otherwise noted.) The soil surface is covered with 40 percent gravel, 5 percent cobbles, and 1 percent stones.

A1--0 to 10 cm; brown (10YR 5/3) very gravelly ashy very fine sandy loam, dark brown (10YR 3/3) moist; weak fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine and fine roots; many very fine interstitial pores; 45 percent angular gravel; slightly acid (pH 6.4); clear wavy boundary. (5 to 15 cm thick)

A2--10 to 18 cm; brown (10YR 5/3) very gravelly ashy sandy loam, dark brown (10YR 3/3) moist; moderate fine and medium subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; common very fine and fine roots; many very fine interstitial and common very fine tubular pores; 10 percent angular cobbles and 40 percent angular gravel; neutral (pH 6.7); clear wavy boundary. (0 to 15 cm thick)

Bt1--18 to 33 cm; brown (10YR 5/3) extremely gravelly ashy loam, dark brown (10YR 3/3) moist; strong fine and medium subangular blocky structure; hard, friable, moderately sticky and moderately plastic; common very fine to medium roots; common very fine interstitial and tubular pores; 10 percent faint clay bridges between sand grains; 15 percent angular cobbles and 50 percent angular gravel; neutral (pH 6.7); clear wavy boundary. (10 to 23 cm thick)

Bt2--33 to 61 cm; brown (10YR 5/3) extremely gravelly ashy loam, dark brown (10YR 3/3) moist; strong fine and medium subangular blocky structure; hard, friable, moderately sticky and moderately plastic; few fine and medium roots and common very fine roots; common very fine interstitial and tubular pores; 10 percent distinct clay films on faces of peds, 10 percent distinct clay films lining pores, and 35 percent faint clay bridges between sand grains; 15 percent angular cobbles and 55 percent angular gravel; neutral (pH 6.6); clear wavy boundary. (15 to 30 cm thick)

2Bt1--61 to 89 cm; brown (7.5YR 5/3) extremely gravelly clay loam, dark brown (7.5YR 3/3) moist; strong fine and medium subangular blocky structure; hard, friable, moderately sticky and moderately plastic; few very fine and fine roots; common very fine interstitial and tubular pores; 35 percent distinct clay films on faces of peds and lining pores; 10 percent angular cobbles and 65 percent angular gravel; neutral (pH 6.7); clear wavy boundary. (20 to 38 cm thick)

2Bt2--89 to 163 cm; reddish yellow (5YR 6/6) extremely gravelly clay, yellowish red (5YR 4/6) moist; moderate medium and coarse subangular blocky structure; hard, friable, very sticky and very plastic; few very fine and fine roots; common fine tubular and very fine interstitial pores; 60 percent distinct clay films on faces of peds and lining pores; 15 percent angular cobbles and 70 percent angular gravel; slightly acid (pH 6.5); abrupt wavy boundary. (38 to 102 cm thick)

2R--163 cm; unweathered quartzite bedrock.

TYPE LOCATION: Mono County, California; in the Bodie Hills about 1.6 kilometers southeast of Mormon Meadow; in a nonsectionized township; USGS Bodie 7.5 minute topographic quadrangle; latitude 38 degrees 08 minutes 49.0 seconds N and longitude 119 degrees 07 minutes 13.5 seconds W; WGS84 Decimal Degrees 38.1469444 latitude, -119.1204167 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist in the moisture control section during late fall, winter, and spring; usually dry July through early October; xeric moisture regime that borders on aridic.
Mean annual soil temperature: 7 to 8 degrees C.
Mollic epipedon thickness: 60 to 100 cm; includes the Bt1, Bt2, and 2Bt3 horizons.
Depth to major lithologic discontinuity: 50 to 100 cm.
Depth to bedrock: 150 to 200 cm to a lithic contact.

Particle-size control section - Clay content: Averages 20 to 30 percent;
Rock fragments: Averages 60 to 85 percent, mainly angular gravel. Lithology of rock fragments are metamorphic rocks such as quartzite or slate.

A horizons
Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 2 or 3, dry or moist.
Texture: Very gravelly ashy very fine sandy loam or very gravelly ashy sandy loam.
Organic matter content: 2 or 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
Chroma: 2 or 3, dry or moist.
Clay content: 18 to 27 percent.
Rock fragments: 60 to 85 percent.
Reaction: Slightly acid or neutral.
Organic matter content: 1 to 3 percent.
Volcanic glass content: 30 to 50 percent in very fine sand and fine sand fractions.

2Bt3 horizon
Hue: 10YR or 7.5YR.
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 2 or 3, dry or moist.
Clay content: 27 to 35 percent.
Rock fragments: 60 to 85 percent.
Reaction: Slightly acid or neutral.
Organic matter content: 0.5 to 2 percent.

2Bt4 horizon
Hue: 7.5YR or 5YR.
Value: 5 or 6 dry, 4 or 5 moist.
Chroma: 4 or 6, dry or moist.
Texture: Extremely gravelly clay loam or extremely gravelly clay.
Clay content: 35 to 45 percent.
Rock fragments: 60 to 85 percent.
Reaction: Slightly acid or neutral.

COMPETING SERIES: There are currently no other series in this family.

GEOGRAPHIC SETTING: Tephzite soils are on hills and mountains. They typically occur on backslope positions. They formed in colluvium and residuum derived from metamorphic rocks such as quartzite or slate 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 4 to 30 percent. Elevations range from 2,135 to 2,680 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 7 degrees C., and the frost-free period is 30 to 60 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Hardteph and Quartzhill soils. Hardteph soils are ashy-skeletal and shallow to lithic contacts. Quartzhill soils are shallow to paralithic contacts.

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

USE AND VEGETATION: Tephzite soils are used for livestock grazing, recreation, watershed, and wildlife habitat. The native vegetation is mainly mountain big sagebrush, antelope bitterbrush, western needlegrass, basin wildrye, currant, and prairie junegrass.

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 89 cm (A1, A2, Bt1, Bt2, and 2Bt3 horizons).
Argillic horizon - The zone from 18 to 163 cm (Bt1, Bt2, 2Bt3, and 2Bt4 horizons).
Vitrandic intergrade feature - The zone from the soil surface to 61 cm (A1, A2, Bt1, and Bt2 horizons).
Major lithologic discontinuity - The change to loamy-skeletal material at 61 cm (between the Bt2 and 2Bt3 horizons).
Lithic contact - The boundary at 163 cm to underlying hard bedrock (2R layer).
Particle-size control section - The zone from 18 to 100 cm (Bt1, Bt2, and 2Bt3 horizons and part of the 2Bt4 horizon).

ADDITIONAL DATA: The typical pedon at the series type location has full characterization data by the Soil Survey Laboratory (SSL), Lincoln, NE, as user pedon ID S06CA051004 (pedon # 07N0054). Volcanic glass content also determined locally by optical grain counts using a polarizing petrographic microscope.

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National Cooperative Soil Survey
U.S.A.