LOCATION SLIPBACK                NV

Established Series
Rev. TEB/RLB/JBF
05/2016

SLIPBACK SERIES

The Slipback series consists of very deep, well drained soils that formed in alluvium derived mainly from granitic rocks. The Slipback soils are on fan piedmont remnants and mountain valley fans. Slopes are 0 to 8 percent. The mean annual precipitation is about 230 mm and the mean annual temperature is about 11 degrees C.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Xeric Natrargids

TYPICAL PEDON: Slipback sandy loam--rangeland. (Colors are for dry soil unless otherwise noted.) The soil surface is partially covered with 5 percent gravel.

A1--0 to 10 cm; pale brown (10YR 6/3) sandy loam, brown (10YR 4/3) moist; weak thin platy structure; soft, very friable, nonsticky and nonplastic; many very fine roots; many fine interstitial pores; 10 percent gravel; moderately alkaline (pH 8.0); abrupt smooth boundary. (5 to 13 cm thick)

A2--10 to 18 cm; very pale brown (10YR 7/3) silt loam, brown (10YR 5/3) moist; weak thin platy structure; slightly hard, very friable, moderately sticky and slightly plastic; common very fine roots; common very fine and few fine tubular pores; 2 percent gravel; moderately alkaline (pH 8.0); abrupt smooth boundary. (0 to 13 cm thick)

AB--18 to 23 cm; pale brown (10YR 6/3) sandy loam, brown (10YR 4/3) moist; weak fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine, common fine and few medium roots; common very fine and fine tubular pores 10 percent gravel; moderately alkaline (pH 8.2); abrupt smooth boundary. (0 to 8 cm thick)

Bt--23 to 33 cm; pale brown (10YR 6/3) gravelly loam, brown (10YR 4/3) moist, weak fine subangular blocky structure; slightly hard, very friable, slightly sticky and moderately plastic; many very fine, few fine, medium and coarse roots; common very fine and fine tubular pores; common thin clay films on ped faces and lining pores; 15 percent gravel; moderately alkaline (pH 8.2); clear smooth boundary. (0 to 15 cm thick)

Btn--33 to 41 cm; yellowish brown (10YR 5/4) gravelly sandy clay loam, dark yellowish brown (10YR 4/4) moist; moderate fine subangular blocky structure; slightly hard, very friable, moderately sticky and moderately plastic; common very fine and fine, few medium roots; many very fine and common fine tubular pores; common thin clay films on ped faces and lining pores; 25 percent gravel; strongly alkaline (pH 8.6); clear wavy boundary. (0 to 20 cm thick)

Btnk--41 to 61 cm; yellowish brown (10YR 5/4) clay loam, dark yellowish brown (10YR 4/4) moist; moderate medium prismatic structure parting to moderate medium subangular blocky; hard, firm, moderately sticky and very plastic; few very fine and fine roots; many very fine and common fine tubular pores; continuous thin clay films on ped faces and lining pores; many fine, medium and coarse carbonate filaments; 5 percent gravel; strongly effervescent; strongly alkaline (pH 8.8); abrupt wavy boundary. (15 to 48 cm thick)

2Bky--61 to 97 cm; yellowish brown (10YR 5/4) gravelly coarse sandy loam, brown (10YR 4/3) moist; massive; slightly hard, very friable, slightly sticky and slightly plastic; few very fine and fine roots; many very fine and few fine tubular pores; 5 percent hard, firm, 2 to 5 mm durinodes; common fine strongly effervescent carbonate filaments; few fine soft masses of gypsum; 15 percent gravel; noneffervescent matrix; moderately alkaline (pH 8.4); gradual smooth boundary. (25 to 50 cm thick)

3Cy---97 to 117 cm; yellowish brown (10YR 5/4) loamy coarse sand, brown (10YR 4/3) moist; massive; slightly hard, very friable, nonsticky and nonplastic; few very fine roots; many very fine and fine interstitial pores; few fine soft masses of gypsum; 10 percent gravel; strongly alkaline (pH 8.6); gradual smooth boundary. (25 to 50 cm thick)

3C--117 to 152 cm; yellowish brown (10YR 5/4) loamy coarse sand, brown (10YR 4/3) moist; massive; slightly hard, very friable, nonsticky and nonplastic; many very fine roots; many very fine and few fine interstitial and tubular pores; 10 percent gravel; strongly alkaline (pH 8.6).

TYPE LOCATION: Pershing County, Nevada; approximately 10 miles east of Mt. Limbo near Juniper Springs, about 2,300 feet west and 2,400 feet north of the southeast corner of section 30, T. 28 N., R. 26 E.; USGS Juniper Pass 7.5 minute topographic quadrangle; latitude 40 degrees 16 minutes 05 seconds N and longitude 119 degrees 06 minutes 24 seconds W; WGS84 Decimal Degrees 40.2676111 latitude, -119.1061111 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Moist in winter and early spring, dry from June through November; aridic soil moisture regime bordering on xeric.
Mean annual soil temperature: 12 to 14 degrees C.
Depth to carbonates: 30 to 64 cm.
Depth to the base of the natric horizon: 50 to 100 cm.

Particle-size control section - Clay content: 25 to 35 percent.
Rock fragments: 5 to 30 percent, mainly fine gravel.

A horizon
Value: 5 through 7 dry, 3 through 5 moist.
Chroma: 1 or 3.

Bt horizons
Hue: 10YR or 2.5Y.
Value: 4 through 6 dry, and 4 or 5 moist.
Chroma: 2 through 4.
Texture: Clay loam, sandy clay loam, loam, gravelly loam or gravelly sandy clay loam.
Structure: Prismatic or subangular blocky with some subhorizon that are prismatic.
Consistence: Slightly hard or hard dry and very friable through firm moist, slightly sticky or sticky and plastic or very plastic wet.
Reaction: Moderately alkaline or strongly alkaline, usually increasing with depth.
Sodicity (SAR): Btn and Btnk horizons range from 13 to 45.
Effervescence: Typically noneffervescent in the upper part and slightly effervescent or violently effervescent in the lower part. Some pedons are violently effervescent in all parts.

2Bk horizons
Hue 10YR or 2.5Y.
Value: 5 through 7 dry, and 4 or 5 moist.
Chroma: 3 or 4.
Texture: Coarse sandy loam, gravelly coarse sandy loam or gravelly sandy loam.
Clay content: 3 to 8 percent.
Rock fragments: 5 to 25 percent mainly fine gravel.
Consistence: Slightly hard or hard dry and very friable or friable moist.
Reaction: Moderately alkaline or strongly alkaline.
Other features: In some pedons there are subhorizons with up to 10 percent durinodes in a friable matrix.

3C horizons
Hue: 10YR or 2.5Y.
Value: 5 through 7 dry, 4 through 6 moist.
Chroma: 3 or 4.
Texture: Loamy coarse sand, sand, coarse sand.
Clay content: 2 to 6 percent.
Rock fragments: 5 to 15 percent, mainly fine gravel. Some pedons have up to 50 percent gravel.
Structure: Horizon is massive or single grained.
Consistence: Loose, soft or slightly hard, dry and loose or very friable moist.
Reaction: Moderately alkaline or strongly alkaline.
Other features: In some pedons these horizons are not present within a depth of 125 cm.

COMPETING SERIES: These are the Antelope Springs, Calnat, Mesma, Tannawasha and Wespac series.

Antelope Springs and Mesman soils have mean annual soil temperatures of less then 12 degrees C. Calnat and Tannawasha soils are moderately deep. Wespac soils contain less than 5 percent rock fragments in the particle-size control section.

GEOGRAPHIC SETTING: Slipback soils are on erosional fan piedmont remnants. These soils formed in alluvium derived mainly from granitic rocks. Slopes are 0 to 8 percent. Elevations are 1,280 to 1,865 meters. The climate is cool, semiarid with cool moist winters and hot, dry summers. The mean annual precipitation is 200 to 250 mm, mean annual temperature is 10 to 13 degrees C, and the frost-free season is 110 to 130 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Deadyon, Granshaw, Nodur and Shawave series. Deadyon and Granshaw soils have a coarse--loamy particle size control section. Nodur soils have weakly cemented Bq horizons. Shawave soils have a fine-loamy particle size control section with 18 to 27 percent clay and a sodium absorption ratio of less than 13 in the argillic horizon.

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 Wyoming big sagebrush, bud sagebrush, bottlebrush squirrel, spiny hopsage and pine bluegrass.

DISTRIBUTION AND EXTENT: Northwest Nevada. These soils are not extensive. MLRA 27,28B.

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

SERIES ESTABLISHED: Pershing County, Nevada, West Part, 1988.

REMARKS: Diagnostic horizons and features recognized in this pedons are:
Ochric epipedon - The zone from the soil surface to 23 cm (A1, A2 and AB horizons).
Natric horizon - The zone from about 33 to 61 cm (Btn and Btnk horizons).
Particle-size control section - The zone from 23 to 61 cm (Bt, Btn and Btnk horizons).

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National Cooperative Soil Survey
U.S.A.