LOCATION FRENTERA                NV

Established Series
Rev. DJ-TM-JVC-JBF
12/2019

FRENTERA SERIES

The Frentera series consists of moderately deep, well drained soils that formed in eolian deposits derived from volcanic ash and colluvium derived from tuff. Frentera soils are on hills and plateaus. Slopes are 15 to 50 percent. The mean annual precipitation is about 330 mm and the mean annual temperature is about 7 degrees C.

TAXONOMIC CLASS: Ashy, glassy, frigid Vitritorrandic Haploxerolls

TYPICAL PEDON: Frentera ashy loam--rangeland. (Colors are for dry soil unless otherwise noted.)

A1--0 to 8 cm; grayish brown (10YR 5/2) ashy loam, very dark grayish brown (10YR 3/2) moist; weak fine granular structure; soft, very friable, slightly sticky and nonplastic; many very fine through medium roots; many fine and very fine interstitial pores; 5 percent gravel; neutral (pH 7.0); clear wavy boundary. (8 to 18 cm thick)

A2--8 to 25 cm; brown (10YR 4/3) gravelly ashy sandy loam, dark brown (10YR 3/3) moist; moderate fine granular structure; soft, very friable, nonsticky and nonplastic; many very fine through medium roots; many fine and very fine interstitial pores; 25 percent gravel; neutral (pH 7.0); abrupt wavy boundary. (18 to 64 cm thick)

Bw1-- 25 to 43 cm; brown (10YR 4/3) ashy sandy loam, dark brown (10YR 3/3) moist; weak fine subangular blocky structure; slightly hard, friable, slightly sticky and nonplastic; many fine roots; few very fine tubular pores; 10 percent gravel; neutral (pH 7.0); clear wavy boundary. (15 to 30 cm thick)

Bw2--43 to 84 cm; brown (10YR 5/3) gravelly ashy sandy loam, dark yellowish brown (10YR 3/4) moist; moderate fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine through medium roots, many fine and very fine tubular pores; 25 percent gravel; neutral (pH 7.0); clear wavy boundary. (15 to 30 cm thick)

2R--84 cm; hard, fractured tuff.

TYPE LOCATION: Humboldt County, Nevada; northwest of Fivemile Flat between the Summit Lake Indian Reservation and the Sheldon National Wildlife Refuge; approximately 150 feet east and 150 feet north of the southwest corner of section 2, T. 42 N., R. 25 E.; USGS Summit Lake 7.5 minute topographic quadrangle; latitude 41 degrees 34 minutes 50 seconds N and longitude 119 degrees 06 minutes 23 seconds W; WGS84 Decimal Degrees 41.5805556 latitude, -119.1063889 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist in winter and spring, dry June through October. They are warmer than 5 degrees C. from April 15 to November 1, and dry after July 1; aridic soil moisture regime that borders on xeric.
Mean annual soil temperature: 7 to 8 degrees C.
Mollic epipedon thickness: 25 to 50 cm, includes the Bw1 horizon in some pedons.
Depth to bedrock: 50 to 100 cm to a lithic contact.

Particle-size control section - Clay content: 12 to 18 percent;
Rock fragments: averages 15 to 35 percent, mainly gravel. Lithology of fragments is volcanic rocks such as rhyolite and tuff;
Volcanic glass content: 30 to 60 percent in coarse silt through fine sand fractions.

A horizons
Value: 2 or 3 moist.
Chroma: 2 or 3 dry.
Organic matter content: 2 to 4 percent.

Bw horizons
Value: 3 or 4 moist.
Texture: Gravelly ashy loam, gravelly ashy sandy loam, or ashy sandy loam.
Rock fragments: 10 to 35 percent.
Organic matter content: 0.5 to 3 percent.
Structure: Weak to moderate subangular blocky structure.
Reaction: Neutral through moderately alkaline.

COMPETING SERIES: These are the Boltz, Bonnick, Borobey, Emamount, Embal, Gardone, Oatmanflat, Picturerock, Stookmoor, Tuffcabin, and Wegert series.

Boltz soils are moderately deep to paralithic contacts. Bonnick, Borobey, Emamount, Embal, Gardone, and Picturerock soils are very deep. Stookmoor soils have firm, brittle horizons within 50 cm of the soil surface. Oatmanflat and Tuffcabin soils are deep to buried duripans. Wegert soils have ashy sandy textures in the particle-size control section and have subhorizons above the lithic contact with greater than 40 percent rock fragments.

GEOGRAPHIC SETTING: Frentera soils are on hills and plateaus. They typically occur on backslope positions. These soils formed in eolian deposits derived from volcanic ash and colluvium derived from tuff. Slopes are 15 to 50 percent. Elevations range from 1,800 to 2,000 meters. The climate is semiarid and characterized by cold, moist winters and warm, dry summers. The mean annual precipitation is 300 to 360 mm, the mean annual temperature is 6 to 7 degrees C, and the frost-free period is 50 to 90 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Tuffo and Wylo soils.

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

USE AND VEGETATION: Frentera soils are used for rangeland and wildlife habitat. The vegetation is mainly Wyoming big sagebrush, Idaho fescue, bluebunch wheatgrass, and Thurber's needlegrass.

DISTRIBUTION AND EXTENT: Northwestern Nevada. These soils are moderately extensive. MLRA 23.

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

SERIES ESTABLISHED: Humboldt County (West Part), Nevada, 1994.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 43 cm (A1, A2, and Bw1 horizons).
Cambic horizon - The zone from 43 to 84 cm (Bw2 horizon).
Vitrandic intergrade feature - The zone from the soil surface to 76 cm (A1, A2, and Bw1 horizons and part of the Bw2 horizon).
Lithic contact - The boundary at 84 cm to underlying hard bedrock (2R layer).
Particle-size control section and ashy substitute class with glassy mineralogy - The zone from 25 to 84 cm (Bw1 and Bw2 horizons).

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National Cooperative Soil Survey
U.S.A.