LOCATION LOPWASH                 NV

Established Series
Rev. OAC/RAF/GJS/JBF
11/2016

LOPWASH SERIES

The Lopwash series consist of very deep, well drained soils that formed in alluvium derived from mixed rocks and loess. Lopwash soils are on inset fans and fan skirts. Slopes are 0 to 4 percent. The mean annual precipitation is about 250 mm and the mean annual temperature is about 7 degrees C.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Typic Haplocambids

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

A--0 to 10 cm; pale brown (10YR 6/3) loam, brown (10YR 4/3) moist; weak medium platy structure; slightly hard, friable, nonsticky and nonplastic; few medium and fine roots; many fine and very fine vesicular pores; l0 percent gravel; strongly alkaline (pH 8.6); abrupt smooth boundary. (10 to 23 cm thick)

Bw--10 to 25 cm; light yellowish brown (10YR 6/4) gravelly loam, dark yellowish brown (10YR 4/4) moist; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common medium, fine, and very fine roots; common fine and very fine interstitial pores; 20 percent gravel; strongly alkaline (pH 8.8); clear smooth boundary. (13 to 18 cm thick)

C--25 to 46 cm; light yellowish brown (10YR 6/4) very gravelly coarse sandy loam, dark yellowish brown (10YR 4/4) moist; massive; soft, very friable, nonsticky and nonplastic; few medium and common fine and very fine roots; common fine and very fine interstitial pores; 55 percent gravel; strongly alkaline (pH 8.8); clear smooth boundary. (18 to 36 cm thick)

Ck1--46 to 81 cm dark yellowish brown (10YR 4/4) moist; massive; soft, very friable, nonsticky and nonplastic; common fine and very fine roots; common fine and very fine interstitial pores; 55 percent gravel; slightly effervescent; strongly alkaline (pH 8.6); clear wavy boundary. (36 to 107 cm thick)

Ck2--81 to 150 cm; light yellowish brown (10YR 6/4) very gravelly loamy sand, dark yellowish brown (10YR 4/4) moist; massive; soft, very friable, nonsticky and nonplastic; common fine and very fine roots; common fine and very fine interstitial pores; 50 percent gravel; slightly effervescent; strongly alkaline (pH 8.6)

TYPE LOCATION: Eureka County, Nevada; approximately 26 miles southwest of Eureka in Antelope Valley about the approximate center of section 4, T. l6 N., R. 50 E.; USGS Sullivan Wash 7.5 minute topographic quadrangle; latitude 39 degrees 17 minutes 15 seconds N and longitude 116 degrees 20 minutes 56 seconds W.; WGS84 Decimal Degrees 39.287500 latitude, -116.3488889 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture; Moist in winter and early spring, dry late May through early November; typic aridic soil moisture regime.
Mean annual soil temperature: 7 to 8 degrees C.
Thickness of A and Bw horizons: 25 to 40 cm.
Depth to carbonates: 36 to 50 cm.

Control section - Clay content: 5 to l8 percent.
Rock fragments: Average 35 to 70 percent.

A horizon
Value: 6 or 7 dry, 4 or 5 moist.
Chroma: 2 or 3.
Reaction: Moderately alkaline or strongly alkaline.

Bw horizon
Value: 5 or 6 dry, 4 or 5 moist.
Chroma: 3 or 4 moist.
Texture: Sandy loam, gravelly sandy loam, loam, or gravelly
loam.
Reaction: Moderately alkaline or strongly alkaline.

C horizon
Value: 6 or 7 dry, 4 or 5 moist
Chroma: 2 through 6.
Texture: Commonly sandy loam, lower portion of some pedons is
loamy sand or sand.
Rock fragments: 35 to 70 percent, mostly gravel.
Reaction: Moderately alkaline or strongly alkaline.

COMPETING SERIES: This is the Unson series. Unson soils are l8 to 35 percent clay in the particle-size control section.

GEOGRAPHIC SETTING: Lopwash soils are on inset fans and fan skirts. These soils formed in alluvium derived from mixed rocks and loess. Slopes are 0 to 4 percent. Elevations are 1,830 to 2,075 meters. The climate is cool, semiarid with cool, moist winters and warm, dry summers. The mean annual precipitation is 200 to 300 mm; mean annual temperature is 7 to 8 degrees C, and the frost-free season is 70 to l00 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Beanflat, Pedoli and Silverado soils. All these soils have less than 35 percent coarse fragments in their control sections.

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

USE AND VEGETATION: Rangeland and wildlife habitat. The present vegetation is mainly shadscale, bud sagebrush, low Douglas rabbitbrush, and winterfat.

DISTRIBUTION AND EXTENT: North-central Nevada. These soils are not extensive. MLRA 28B.

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

SERIES ESTABLISHED: Eureka County, Nevada, l983.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the surface to 18 cm (A and part of the Bw horizons).
Cambic horizon - The zone from 10 to 25 cm (Bw horizon).
Particle-size control section - The zone from 25 to 100 cm
(C, Ck1 horizons and part of the Ck2 horizons).

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National Cooperative Soil Survey
U.S.A.