LOCATION WALKERIVER              NV

Established Series
Rev. JBF-JVC
05/2016

WALKERIVER SERIES

The Walkeriver series consists of very deep, well drained soils that formed in volcanic ash and alluvium derived from mixed igneous rocks. Walkeriver soils are on stream terraces. Slopes are 0 to 4 percent. The mean annual precipitation is about 130 mm and the mean annual temperature is about 13 degrees C.

TAXONOMIC CLASS: Sandy, mixed, mesic Vitrandic Torrifluvents

TYPICAL PEDON: Walkeriver ashy loamy fine sand--irrigated cropland. (Colors are for dry soil unless otherwise noted.)

Ap--0 to 15 cm; brown (10YR 5/3) ashy loamy fine sand, dark brown (10YR 3/3) moist; weak thin platy structure parting to moderate medium subangular blocky; soft, very friable, nonsticky and nonplastic; few very fine and fine roots; few fine tubular and common fine interstitial pores; neutral (pH 7.0); clear smooth boundary. (10 to 15 cm thick)

A--15 to 28 cm; brown (10YR 5/3) ashy fine sandy loam, brown (10YR 4/3) moist; moderate medium subangular blocky structure; soft, very friable, slightly sticky and nonplastic; few very fine and fine roots; few fine tubular pores; neutral (pH 7.0); clear smooth boundary. (2 to 15 cm thick)

C1--28 to 56 cm; brown (10YR 5/3) ashy sand, brown (10YR 4/3) moist; single grain; loose, nonsticky and nonplastic; few very fine and fine roots; common very fine and fine interstitial pores; neutral (pH 7.0); clear smooth boundary.

C2--56 to 66 cm; light brownish gray (10YR 6/2) ashy very fine sandy loam, brown (10YR 4/3) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; common very fine interstitial pores; 10 percent fine and medium distinct brownish yellow (10YR 6/6) moist relict masses of iron accumulation; neutral (pH 7.2); clear smooth boundary.

C3--66 to 99 cm; pale brown (10YR 6/3) ashy sand, dark grayish brown (10YR 4/2) moist; single grain; loose, nonsticky and nonplastic; few fine roots; common very fine interstitial pores; 2 percent fine distinct brownish yellow (10YR 6/6) moist relict masses of iron accumulation; neutral (pH 7.2); abrupt smooth boundary.

C4--99 to 152 cm; pale brown (10YR 6/3) stratified ashy silt loam to ashy sand, dark grayish brown (10YR 4/2) moist; massive and single grain; slightly hard and loose, very friable and loose, slightly sticky and slightly plastic, loamy strata are nonsticky and nonplastic sandy strata; few fine roots; common very fine tubular and interstitial pores; 2 percent fine distinct brownish yellow (10YR 6/6) moist relict masses of iron accumulation; slightly alkaline (pH 7.4). (Combined thickness of the C horizons is 122 to 140 cm)

TYPE LOCATION: Mineral County, Nevada; on the Walker River Indian Reservation about 4.75 miles southeast of Schurz; approximately 1,760 feet east and 2,400 feet north of the southwest corner of section 16, T. 12 N., R. 29 E.; USGS Gillis Canyon NW 7.5 minute topographic quadrangle; 38 degrees 54 minutes 08.3 seconds north latitude and 118 degrees 44 minutes 56.9 seconds west longitude; WGS84 Decimal Degrees 38.9023056 latitude, -118.7491389 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist in some part of the moisture control section for short periods during winter and early spring, dry from later spring through fall unless irrigated; Typic torric moisture regime.
Mean annual soil temperature: 12 to 14 degrees C.
Depth to seasonal high water table: Greater than 150 cm.
Reaction Neutral through moderately alkaline.
Other features Organic carbon decreases irregularly with depth due to stratification of textures; Relict masses of iron and manganese accumulation are common in most pedons.

Particle-size control section - Clay content: Averages 2 to 10 percent; Volcanic glass content: Averages less than 30 percent in coarse silt through very coarse sand fractions.

Ap and A horizons
Value: 2 or 3 moist.
Chroma: 2 or 3, dry or moist.
Volcanic glass content: 10 to 30 percent in coarse silt through fine sand fractions.
Oxalate aluminum plus one-half oxalate iron: 0.1 to 0.4 percent.

C horizons
Hue: 10YR or 2.5Y.
Value: 5 through 7 dry, 3 through 5 moist.
Chroma: 2 through 4, dry or moist.
Texture: Stratified coarse sand to ashy silt loam.
Salinity (EC): 0 to 4 mmhos/cm.
Sodicity (SAR): 0 to 5.
Volcanic glass content: 5 to 30 percent in coarse silt through fine sand fractions.
Oxalate aluminum plus one-half oxalate iron: 0.1 to 0.4 percent.

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

GEOGRAPHIC SETTING: Walkeriver soils are on stream terraces. They formed in volcanic ash and alluvium derived from mixed igneous rocks such as granodiorite and andesite. Slopes are 0 to 4 percent. Elevations range from 1,200 to 1,310 meters. The climate is arid with cool, moist winters and hot, dry summers. The mean annual precipitation is 100 to 150 mm, the mean annual temperature is 11 to 13 degrees C., and the frost-free period is 130 to 150 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Schurz and Slawmaster soils. Schurz soils are ashy and average 8 to 18 percent clay in the particle-size control section. Slawmaster soils are fine-silty.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; very low or low surface runoff; high saturated hydraulic conductivity. These soils are susceptible to rare flooding year-round.

USE AND VEGETATION: Walkeriver soils are used mainly for irrigated cropland, rangeland, wildlife habitat, and some urban development. Alfalfa hay is the main crop. The vegetation in rangeland is mainly black greasewood, Torrey quailbush, and rabbitbrush.

DISTRIBUTION AND EXTENT: Western Nevada. These soils are not extensive with about 2,900 acres of the series mapped to date. MLRA 27.

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

SERIES ESTABLISHED: Mineral County Area, Nevada, 2005.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 18 cm (Ap and part of the A horizons).
Vitrandic intergrade feature - The zone from the soil surface to 152 cm (Ap, A, C1, C2, C3 and C4 horizons).
Particle-size control section - The zone from 25 to 100 cm (C1, C2, and C3 horizons and parts of the A and C4 horizons).

ADDITIONAL DATA: Volcanic glass content determined locally by optical grain count with a polarizing petrographic microscope.

---

National Cooperative Soil Survey
U.S.A.