LOCATION SLAWHA                  NV

Established Series
Rev. DJ/RLB/TM/JBF
03/2016

SLAWHA SERIES

The Slawha series consists of very deep, well drained soils that formed in alluvium derived from mixed rock sources. Slawha soils are on alluvial flats, flood plains, and low river terraces. Slopes are 0 to 2 percent. The mean annual precipitation is about 150 mm and the mean annual temperature is about 11 degrees C.

TAXONOMIC CLASS: Fine-silty, mixed, superactive, calcareous, mesic Typic Torrifluvents

TYPICAL PEDON: Slawha silt loam, 0 to 2 percent slopes. (Colors are for dry soil unless otherwise noted.)

A1--0 to 13 cm; light gray (10YR 7/2) silt loam, grayish brown (10YR 5/2) moist; moderate medium platy structure; slightly hard, very friable, slightly sticky and slightly plastic; few very fine and fine roots; common very fine and fine tubular pores; strongly effervescent; strongly alkaline (pH 8.6); clear smooth boundary. (3 to 13 cm thick)

A2--13 to 33 cm; light gray (10YR 7/2) silt loam, grayish brown (10YR 5/2) moist; weak fine granular structure; soft, very friable, slightly sticky and slightly plastic; common very fine and fine roots; common very fine and fine tubular pores; strongly effervescent; very strongly alkaline (pH 9.1); clear smooth boundary. (5 to 20 cm thick)

C1--33 to 43 cm; light gray (10YR 7/2) silt loam, grayish brown (10YR 5/2) moist; massive; soft, very friable, slightly sticky and slightly plastic; common very fine and medium roots; common very fine and fine tubular pores; violently effervescent; strongly alkaline (pH 9.0); clear smooth boundary. (8 to 20 cm thick)

C2--43 to 69 cm; light gray (2.5Y 7/2) silty clay loam, grayish brown (2.5Y 5/2) moist; massive; hard, firm, moderately sticky and moderately plastic; few very fine and fine roots; few very fine and fine tubular pores; violently effervescent; very strongly alkaline (9.2); clear smooth boundary. (13 to 38 cm thick)

C3--69 to 107 cm; light gray (2.5Y 7/2) silty clay loam, grayish brown (2.5Y 5/2) moist; massive; hard, friable, moderately sticky and moderately plastic; few very fine and fine roots; few very fine and fine tubular pores; strongly effervescent; very strongly alkaline (9.2); clear smooth boundary. (28 to 46 cm thick)

C4--107 to 152 cm; pale yellow (2.5Y 7/4) silty clay loam, olive brown (2.5Y 4/4) moist; few distinct mottles yellow (10YR 7/8), brownish yellow (10YR 6/6) moist; massive; hard, friable, moderately sticky and moderately plastic; few very fine and fine roots; few very fine tubular pores; violently effervescent; very strongly alkaline (pH 9.2).

TYPE LOCATION: Humboldt County, Nevada; approximately 2.5 miles north of Deer Creek Ranch, about 1500 feet east and 1800 feet south of the northwest corner of section 10, T. 41 N., R 31 E.; USGS Deer Creek Peak 7.5 minute topographic quadrangle; latitude 41 degrees 26 minutes 37 seconds N and longitude 118 degrees 29 minutes 50 seconds W; WGS84 Decimal Degrees 41.4436111 latitude, -118.4972222 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Moist in winter and spring, dry July through October; typic aridic soil moisture regime.
Mean annual soil temperature: 9 to 13 degrees C.
Calcium carbonate: Average 1 to 4 percent.
Organic matter: Decrease irregularly with depth.
Reaction: Strongly alkaline or very strongly alkaline.
Sodium absorption ratio (SAR): 0 to 30.

Particle-size control section - Clay content: 18 to 35 percent.

A horizon
Value: 6 or 7 dry, 4 through 6 moist.
Chroma: 2 through 4.
Carbonates: Slightly effervescent to violently effervescent.
Electrical conductivity (EC): 4 to 16 percent.


C horizon
Hue: 10YR or 2.5Y
Value: 6 through 8 dry, 4 through 6 moist.
Chroma: 2 through 4.
Texture: Averages silty clay loam or silt loam, includes strata of loam or silty clay.
Structure: Subangular blocky, platy or is massive.
Carbonates: Strongly effervescent to violently effervescent.
Electrical conductivity (EC): 4 to 16 percent.
Relict redoximorphic features: Might be in any subhorizon.

COMPETING SERIES: These are Fivemile, Slaw and Tours series.

Fivemile soils have 4 to 10 percent calcium carbonate in the C horizon. Tours soils are moist in the soil moisture control section during July and August and have redder hues. Slaw soils are moist 10 to 20 days from July to October following the summer solstice.

GEOGRAPHIC SETTING: Slawha soils are on flood plains, low river terraces and alluvial flats. These soils formed in alluvium derived from mixed sources. Slopes are 0 to 4 percent. Elevations are 1,070 to 1,280 meters. The climate is cool, arid with hot, dry summers and cool, moist winters. The mean annual precipitation is 125 to 200 mm; mean annual temperature is 8 to 12 degrees C., and the frost-free season is 120 to 140 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are Boton and Sondoa soils. Boton and Sondoa soils have regular decreasing organic matter with depth. Boton soils have weakly or strongly cemented durinodes.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; slow or very slow runoff; moderately low saturated hydraulic conductivity.

USE AND VEGETATION: Livestock grazing, urban land, cropland and wildlife habitat. The present vegetation is mainly black greasewood, quailbush and seepweed.

DISTRIBUTION AND EXTENT: Northwestern Nevada. Slawha soils are of small extent. MLRA 24 and 27.

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

SERIES ESTABLISHED: Humboldt County, Nevada, West Part. 1993

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the surface to 18 cm (A1 and part of A2 horizons).
Torrifluvent feature - Irregular decreases in organic carbon.
Particle-size control section - The zone from 25 to 100 cm (C1, C2 and part of A2 amd C3 horizons)..

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National Cooperative Soil Survey
U.S.A.