LOCATION WYVA                    NV

Established Series
Rev. DJM/RLB/JBF
07/2016

WYVA SERIES

The Wyva series consists of shallow, well drained soils that formed in residuum and colluvium derived from volcanic rocks. The Wyva soils are on mountains and hills. Slopes are 15 to 50 percent. The mean annual precipitation is about 280 mm and the mean annual temperature is about 13 degrees C.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic Lithic Ustic Haplargids

TYPICAL PEDON: Wyva very cobbly sandy loam--rangeland. (Colors are for dry soil unless otherwise noted.) The surface is partially covered with 30 percent cobbles and 25 percent gravel.

A--0 to 5 cm; brown (10YR 5/3) very cobbly sandy loam, dark brown (10YR 3/3) moist; moderate fine granular structure; soft, very friable, slightly sticky and slightly plastic; many very fine roots; many very fine and fine interstitial pores; 25 percent cobbles and 20 percent gravel; slightly alkaline (pH 7.6); abrupt smooth boundary. (5 to 8 cm thick)

Bt1--5 to 20 cm; brown (7.5YR 5/4) very cobbly loam, dark brown (7.5YR 3/4) moist; moderate fine subangular blocky structure; hard, friable, moderately sticky and moderately plastic; many very fine and fine roots; many very fine and fine tubular pores; common distinct clay films lining pores and on faces of peds; 30 percent cobbles and 20 percent gravel; slightly alkaline (pH 7.6); clear smooth boundary. (13 to 22 cm thick)

Bt2--20 to 38 cm; brown (7.5YR 5/4) extremely cobbly clay loam, brown (7.5YR 4/4) moist; moderate fine and medium subangular blocky structure; hard, friable, very sticky and very plastic; common very fine and fine and few medium roots; common fine tubular pores; many distinct clay films lining pores and on faces of peds; 50 percent cobbles, 20 percent gravel; slightly alkaline (pH 7.6); abrupt wavy boundary. (10 to 22 cm thick)

R--38 cm; rhyolite.

TYPE LOCATION: Lincoln County, Nevada; approximately 475 feet south and 5 feet west of the northeast corner of section 24, T. 4 S., R. 64 E.; USGS Pahroc Spring SE 7.5 minute topographic quadrangle; latitude 37 degrees 35 minutes 29 seconds N and longitude 114 degrees 45 minutes 5 seconds W; WGS84 Decimal Degrees xx.xxxxxx latitude, xxx.xxxxxx longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually dry, moist in late summer; aridic soil moisture regime bordering on ustic.
Mean annual soil temperature: 12 to 14 degrees C.
Depth to bedrock: 36 to 50 cm.

Particle-size control Section - Clay content: Averages 27 to 35 percent. Sand: Less than 50 percent.
Rock fragments: Averages 35 to 65 percent.

A horizon
Value: 4 or 5 dry.
Chroma: 2 or 3 moist.

Bt1 horizon
Hue: 10YR or 7.5YR.
Value: 4 or 5 dry, 3 or 4 moist.
Clay content: 20 to 35 percent.
Texture: Loam or clay loam.
Rock fragments: 35 to 55 percent, cobbles and gravel.
Structure: Moderate fine granular or subangular blocky.

Bt2 horizon
Hue: 10YR or 7.5YR.
Chroma: 3 or 4 moist.
Clay content: 27 to 35 percent.
Rock fragments: 40 to 75 percent.
Structure: Moderate or strong subangular blocky.

COMPETING SERIES: These are the Fourmilebench, Puertecito, Quazo and Roygorge soils.

Fourmilebench have 12 to 20 percent clay in the particle-size control section. Puertecito soils have 8 to 13 percent calcium carbonate equivalent in the lower part of the Bt horizon. Quazo soils are moist for 30 to 40 days during the summer months and contains more than 50 percent sand in the particle-size control section. Roygorge soils have an average sand content of greater than 50 percent in the particle-size control section and are moist more than 60 consecutive days, April through September.

GEOGRAPHIC SETTING: Wyva soils are on mountains and hills. These soils formed in rhyolite, andesite, and volcanic tuffs. Slopes are 15 to 50 percent. Elevations are 1,260 to 1,925 meters. The climate is semi-arid with cool moist winters and warm dry summers. The mean annual precipitation is 250 to 300 mm, the mean annual temperature is 10 to 13 degrees C, and the frost-free season is 120 to 180 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Slidymtn, Hollace, Rochpah, Winklo, and Kanesprings soils. Slidymtn soils have a mollic epipedon. Hollace soils are shallow over a petrocalcic horizon. Rochpah soils lack an argillic horizon. Winklo soils have a fine particle-size control section and are moderately deep to bedrock. Kanesprings soils are shallow over a duripan.

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

USE AND VEGETATION: Rangeland and wildlife habitat. The present vegetation is mainly Wyoming big sagebrush, green ephedra, blue grama, and bluegrass.

DISTRIBUTION AND EXTENT: Southeastern Nevada. Wyva soils are of moderate extent. MLRA 29.

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

SERIES ESTABLISHED: Lincoln County, Nevada, (South part), 1992.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 5 cm (A horizon).
Argillic horizon - The zone from 5 to 38 cm (Bt1 and Bt2 horizons)
Ustollic feature - Meets organic carbon requirement for "Ustollic".
Lithic contact - The contact with hard rock at 38 cm (R layer)
Particle-size control section - The zone from 5 to 38 cm (Bt horizons).

ADDITIONAL DATA: Characterization data on a similar pedon available for samples S86NV-017-006(1-3).

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National Cooperative Soil Survey
U.S.A.