LOCATION EWELAC                  NV

Established Series
Rev. GWM/TM/JBF
12/2019

EWELAC SERIES

The Ewelac series consists of very deep, moderately well drained soils that formed in lacustrine deposits. The Ewelac soils are on lake plains, basin floors, and alluvial flats. Slopes are 0 to 4 percent. The mean annual precipitation is about 180 mm and the mean annual temperature is about 8 degrees C.

TAXONOMIC CLASS: Fine, smectitic, mesic Vertic Haplocambids

TYPICAL PEDON: Ewelac silty clay--rangeland. (Colors are for dry soil unless otherwise noted.)

An--0 to 13 cm; dark grayish brown (2.5Y 4/2) silty clay, very dark grayish brown (2.5Y 3/2) moist; moderate medium subangular blocky structure parting to moderate fine subangular blocky; slightly hard, friable, very sticky and very plastic; many very fine and fine roots; many very fine and fine interstitial pores; very slightly saline; violently effervescent; very strongly alkaline (pH 9.4); clear smooth boundary. (8 to 13 cm thick)

Bn--13 to 36 cm; grayish brown (2.5Y 5/2) silty clay, dark grayish brown (2.5Y 4/2) moist; moderate medium subangular blocky structure parting to moderate fine subangular blocky; hard, firm, very sticky and very plastic; many fine and few medium roots; common very fine and fine tubular pores; slightly saline; strongly sodic; violently effervescent; very strongly alkaline (pH 9.6); clear smooth boundary. (0 to 25 cm thick)

Bnz--36 to 71 cm; light brownish gray (2.5Y 6/2) silty clay, grayish brown (2.5Y 5/2) moist; moderate coarse prismatic structure parting to moderate medium subangular blocky; hard, firm, very sticky and very plastic; common fine and few medium roots; common very fine and fine tubular pores; moderately saline; strongly sodic; common very fine rounded salt masses; violently effervescent; very strongly alkaline (pH 9.2); clear smooth boundary. (18 to 50 cm)

Bkn--71 to 107 cm; light gray (2.5Y 7/2) silty clay, grayish brown (2.5Y 5/2) moist; weak medium subangular blocky structure parting to moderate fine and very fine granular; slightly hard, friable, moderately sticky and very plastic; few fine and medium roots; common fine tubular pores; slightly saline; moderately sodic; few medium irregular masses of secondary calcium carbonate; violently effervescent; strongly alkaline (pH 9.0); clear smooth boundary. (13 to 64 cm)

Bkg--107 to 152 cm; white (5Y 8/1) silty clay, light brownish gray (2.5Y 6/2) moist; weak medium subangular; hard, firm, moderately sticky and very plastic; few fine and medium roots; many medium and coarse tubular continuous pores; few medium and coarse rounded and irregular masses of secondary calcium carbonate, few fine secondary calcium carbonate nodules; common distinct and prominent yellow (2.5Y 7/6) irregular shaped iron concentrations on ped faces; violently effervescent; strongly alkaline (pH 8.8).

TYPE LOCATION: White Pine County, Nevada; approximately 1.2 miles east of the North Spring Valley highway on the Rogers Ranch road and 50 feet north in rangeland; 2,520 feet east and 350 feet north of the southwest corner of Sec. 32, T. 17 N., R. 67 E.; USGS Yelland Dry Lake 7.5-minute topographic quadrangle; latitude 39 degrees 17 minutes 23 seconds N and longitude 114 degrees 27 minutes 46 seconds W; WGS84 Decimal Degrees 39.2897222
latitude, -114.4627778 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Saturated between depths of 107 to 150 cm in the early spring and usually moist at this depth due to capillarity from ground water. Soil moisture control section (10 to 30 cm depth) is usually dry in summer and fall except for 10 to 20 days cumulative from July through September due to convection storms.
Mean annual soil temperature: 8 to 11 degrees C.
Reaction: Strongly alkaline or very strongly alkaline.
Calcium carbonate equivalent: 25 to 35 percent.
Other features: Where the soil surface in not vegetated, the surface is highly dispersed and contains powdery white crystalline salt accumulations at a depth of 8 to 13 cm below the surface.

Particle-size control section - Clay content: 35 to 50 percent.

An horizon
Hue: 2.5Y or 5Y.
Value: 4 or 5 dry, 3 or 4 moist.
Chroma: 2 or 3, dry or moist.
Electrical conductivity (EC): 0 to 4 dS/m.
Sodicity (SAR): 13 to 30.

Bn horizon (when present)
Hue: 2.5Y or 5Y.
Value: 4 or 5 dry, 3 or 4 moist.
Chroma: 2 or 3, dry or moist.
Texture: Silty clay or silty clay loam.
Electrical conductivity (EC): 4 to 8 dS/m.
Sodisodicity (SAR): 46 to 90

Bnz horizon
Hue: 2.5Y or 5Y.
Value: 5 or 6 dry, 4 or 5 moist.
Chroma: 2 or 3, dry or moist.
Texture: Silty clay or silty clay loam.
Electrical conductivity (EC): 8 to 16.dS/m.
Sodicity (SAR): 46 to 90.
Structure: Moderate medium or coarse prismatic or columnar structure parting to subangular blocky.

Bkn horizon
Hue: 2.5Y or 5Y.
Value: 6 or 7 dry, 5 or 6 moist.
Chroma: 2 or 3, dry or moist.
Texture: Silty clay or silty clay loam.
Electrical conductivity (EC): 4 to 8 dS/m.
Sodicity (SAR): 31 to 45.
Visible secondary carbonates range from 1 to 4 percent.

Bkg horizon
Hue: 2.5Y or 5Y.
Value: 7 or 8 dry, 6 or 7 moist.
Chroma: 1 or 2, dry or moist.
Electrical conductivity (EC): 0 to 4 dS/m.
Sodicity (SAR): 1 to 5.
Visible secondary calcium carbonates: 1 to 4 percent.
Structure: Subangular blocky or massive.

COMPETING SERIES: There are no competing series.

GEOGRAPHIC SETTING: The Ewelac soils are on lake plains, basin floors, and alluvial flats. These soils formed in lacustrine sediments. Slopes are 0 to 4 percent. Elevations are 1,390 to 1,830 meters. The climate is cool, semiarid with cool, moist winters and warm, dry summers. The mean annual precipitation is 150 to 200 mm, mean annual temperature is 7 to 10 degrees C, and the frost-free season is 100 to 120 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Medlaval, Biji, Kolda, and Duffer soils.

The Biji soils have a calcic horizon. The Medlaval soils have a mollic epipedon. Kolda and Duffer soils have aquic moisture regimes.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Moderately well drained; medium or high runoff; moderately low saturated hydraulic conductivity.

USE AND VEGETATION: Ewelac soils are used for livestock grazing and wildlife habitat. The present vegetation is black greasewood, iodinebush, shadscale and inland saltgrass.

DISTRIBUTION AND EXTENT: East-central Nevada. MLRA 28A. These soils are not extensive.

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

SERIES ESTABLISHED: White Pine County, Nevada, East Part, 2004. The name is coined.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 18 cm (An and part of the Bn horizons).
Cambic horizon - The zone from 13 to 71 cm (Bn and Bnz horizons).
Seasonal water table - Within a depth of 107 to 150 cm.
Particle-size control section - The zone from 25 to 100 cm. (part of the Bn horizon, Bnz, Bkn and part of the Bkg horizon)

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National Cooperative Soil Survey
U.S.A.