LOCATION EQUIS                   NV

Established Series
Rev. WM-RLB-JBF
11/2016

EQUIS SERIES

The Equis series consists of very deep, poorly drained soils that formed in lacustrine sediments and alluvium derived from mixed rocks. Equis soils are on alluvial flats, floodplains and lake plains. Slopes are 0 to 2 percent. The mean annual precipitation is about 200 mm and the mean annual temperature is about 8 degrees C.

TAXONOMIC CLASS: Fine, carbonatic, mesic Typic Halaquepts

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

A--0 to 15 cm; light gray (5Y 7/1) silty clay, gray (5Y 6/1) moist; strong very coarse and coarse prismatic structure; very hard, very firm, very sticky and very plastic; many very fine and fine roots; common fine tubular pores; top 2 cm has strong fine angular blocky structure; strongly effervescent; strongly alkaline (pH 9.0); clear wavy boundary. (10 to 18 cm thick)

Bg1--15 to 50 cm; white (5Y 8/1) silty clay, gray (5Y 6/1) moist; weak coarse prismatic structure parting to strong fine angular blocky; very hard, very firm, very sticky and very plastic; common fine roots; few fine tubular pores; many fine prominent light yellowish brown redox concentrations; strongly effervescent; strongly alkaline (pH 9.0); clear wavy boundary. (28 to 50 cm thick)

Bg2--50 to 76 cm; white (10YR 8/1) silty clay, light gray (10YR 7/2) moist; strong fine angular blocky structure; very hard, very firm, very sticky and very plastic; few fine roots; few fine tubular pores; strongly effervescent; strongly alkaline (pH 9.0); clear wavy boundary. (18 to 36 cm thick)

Bkg1--76 to 104 cm; white (10YR 8/1) silty clay, light gray (10YR 7/2) moist; moderate fine angular blocky structure; very hard, very firm, very sticky and very plastic; few fine roots; few fine tubular pores; few fine soft masses of carbonate; strongly effervescent; strongly alkaline (pH 8.5); clear smooth boundary. (15 to 30 cm thick)

Bkg2--104 to 127 cm; white (10YR 8/1) silty clay loam, light gray (10YR 7/2) moist; moderate fine angular blocky structure; very hard, very firm, very sticky and very plastic; few fine roots; few fine tubular pores; few fine soft masses of carbonate; strongly effervescent; strongly alkaline (pH 8.5); clear smooth boundary. (18 to 30 cm thick)

Cg--127 to 152 cm; white (10YR 8/1) silt loam, light gray (10YR 7/2) moist; massive; very hard, very firm, moderately sticky and moderately plastic; very few fine roots; very few fine tubular pores; common snail shell fragments; strongly effervescent, strongly alkaline (pH 8.5).

TYPE LOCATION: White Pine County, Nevada, about 45 miles north of Ely, 1,500 feet west and 200 feet north of the southeast corner of section 13, T. 22 N., R. 63 E.; USGS Borchert Spring 7.5 minute quadrangle; latitude 39 degrees 46 minutes 8 seconds N and longitude 114 degrees 47 minutes 59 seconds W; WGS84 Decimal Degrees 39.7688889 latitude, -114.7997222 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Moist at or near the surface. Saturated at a depth of 13 to 50 cm in most years. Depth to the water table ranges from about 30 cm in the spring to 150 cm in late summer.
Mean annual soil temperature: 9 to 11 degrees C.
Reaction - Strongly alkaline or very strongly alkaline.
Sodicity (SAR): 20 to 70 percent in the upper 50 cm, decreasing to less than 5 percent below 50 cm.
Calcium carbonate equivalent - 45 to 65 percent. Clay sized carbonates range from 30 to 45 percent in the upper 76 cm.

Particle-size control section - Clay content: 40 to 50 percent silicate clay, 30 to 45 percent carbonates of clay size.

A horizon
Hue: 10YR through 5Y or N.
Value: 6 through 8 dry, 4 through 7 moist.
Chroma: 0 through 2
Effervescence: Strongly effervescent or violently effervescent.

Bg horizon
Hue: 10YR through 5Y or N.
Value: 6 through 8 dry, 4 through 7 moist.
Chroma: 0 through 2
Texture: Silty clay or clay
Structure: Prismatic or angular blocky.
Consistence: Hard to very hard, very friable to firm.
Reaction: Strongly alkaline or very strongly alkaline.

Bkg horizon
Hue: 5Y through 10YR or N.
Value: 6 through 8 dry, 5 through 7 moist.
Chroma: 0 through 3
Structure: Angular blocky or massive.
Texture: Silty clay or silty clay loam.
Clay content: 30 to 45 percent silicate clay, 18 to 30 percent carbonates of clay size.
Consistence: Hard or very hard, friable to very firm, sticky or very sticky, plastic to very plastic.
Other features: Some pedons have prominent redox concentrations.

Cg Horizon
Texture: Silt loam, silty clay loam or silty clay.
Consistence: Hard to very hard, friable to very firm, moist.
Other features: Some pedons lack snail shell fragments.

COMPETING SERIES: There are no competing series

GEOGRAPHIC SETTING: Equis soils are on alluvial flats, floodplains and lake plains. These soils formed in limy lacustrine sediments, in some places recently mantled with alluvium. Elevations are 1,560 to 1,920 meters. Slopes are 0 to 2 percent. The mean annual precipitation is 200 to 250 mm. The mean annual temperature is 7 to 10 degrees C. The frost-free period is 100 to 120 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Boofus and Duffer soils. Boofus soils have a clayey over loamy particle-size control section. Duffer soils have a fine-silty particle-size control section.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Poorly drained; slow to ponded runoff; moderately low saturated hydraulic conductivity. Drained phases and rarely flooded phases are recognized adjacent to springs, seeps and ponds. Frequently flooded phases are recognized adjacent to stream channels.

USE AND VEGETATION: Livestock grazing and wildlife habitat. The vegetation is mainly black greasewood, rubber rabbitbrush, inland saltgrass, alkali sacaton, iodinebush and scattered sedges.

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

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

SERIES ESTABLISHED: White Pine County, Nevada, West Part, 1990.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to a depth of 18 cm (A and part of Bg1 horizons).
Redox concentrations - The zone from 15 to 50 cm (Bg1 horizon).
Exchangeable sodium percent - Greater than 20 in the upper 50 cm decreasing with depth.
Seasonal high water table - Within 30 to 90 cm at some time during the period February to April.
Particle-size control section - The zone from 25 to 100 cm (part of the Bg1, Bg2 and part of the Bkg1 horizons).

ADDITIONAL DATA: NSSL Data- 81P3977- 3984; S81NV-033-032.

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National Cooperative Soil Survey
U.S.A.