LOCATION UNSEL NV

Established Series
Rev. GAR-WED-JVC-JBF
07/2016

UNSEL SERIES

The Unsel series consists of very deep, well drained soils that formed in alluvium derived from mixed rocks. Unsel soils are on fan remnants and fan skirts. Slopes are 0 to 30 percent. The mean annual precipitation is about 150 mm and the mean annual temperature is about 12 degrees C.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Durinodic Haplargids

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

A--0 to 10 cm; light gray (10YR 7/2) gravelly loam, dark grayish brown (10YR 4/2) moist; massive; slightly hard, very friable, slightly sticky and slightly plastic; many very fine and fine vesicular and few very fine and fine tubular pores; 25 percent gravel; violently effervescent; very strongly alkaline (pH 9.2); abrupt wavy boundary. (5 to 20 cm thick)

Btk1--10 to 18 cm; pale brown (10YR 6/3) gravelly clay loam, brown (7.5YR 5/4) moist; weak medium prismatic structure parting to weak fine and medium subangular blocky; slightly hard, very friable, moderately sticky and moderately plastic; common very fine roots; few very fine and fine tubular pores; few faint clay films on faces of peds, lining pores, and bridging sand grains; 20 percent gravel; secondary carbonates segregated as few fine and medium masses; noneffervescent matrix and strongly and violently effervescent carbonate masses; moderately alkaline (pH 8.4); abrupt wavy boundary. (5 to 26 cm thick)

Btk2--18 to 25 cm; pale brown (10YR 6/3) gravelly clay loam, yellowish brown (10YR 5/4) moist; weak fine and medium subangular blocky structure; slightly hard, very friable, moderately sticky and moderately plastic; common very fine and fine roots; few very fine tubular pores; few distinct clay films on faces of peds, lining pores, and bridging sand grains; 25 percent gravel; noneffervescent matrix, strongly and violently effervescent segregated fine and medium carbonate masses; strongly alkaline (pH 8.6); abrupt smooth boundary. (0 to 20 cm thick)

Bqk--25 to 79 cm; pale brown (10YR 6/3) gravelly sandy loam in pockets with thin strata of very gravelly loamy sand and sand, brown (10YR 4/3) moist; massive; soft, very friable, nonsticky and nonplastic; few very fine roots; few very fine tubular pores; discontinuous strongly silica-cemented strata which are firm and brittle when moist and 30 percent discontinuous laminae of opaline silica; 30 percent gravel; secondary carbonates segregated as common coats on bottoms of rock fragments; violently effervescent; strongly alkaline (pH 8.6); abrupt smooth boundary. (15 to 61 cm thick)

2C--79 to 152 cm; very pale brown (10YR 7/3) extremely gravelly sand, brown (10YR 5/3) and very dark grayish brown (10YR 3/2) moist; massive; soft, very friable; nonsticky and nonplastic; few very fine roots; 60 percent gravel; violently effervescent; strongly alkaline (pH 8.6).

TYPE LOCATION: Nye County, Nevada; in Big Smoky Valley about 1.5 miles northwest of the mouth of West Northumberland Canyon and 530 feet south of the access road to the canyon; about 1,400 feet north and 805 feet west of the southeast corner of section 26, T. 14 N., R. 44 E.; USGS Wildcat Canyon 7.5 minute topographic quadrangle; latitude 39 degrees 02 minutes 24 seconds N and longitude 116 degrees 59 minutes 47 seconds W; WGS84 Decimal Degrees 39.0400000 latitude, -116.9963889 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist in some part of the moisture control section for short periods during winter and early spring months and intermittently moist for 10 to 20 days cumulative between July and September due to convection storms, typic aridic soil moisture regime.
Mean annual soil temperature: 12 to 15 degrees C.
Ochric epipedon thickness: 5 to 20 cm.
Depth to base of argillic horizon and upper zone of silica accumulation: 25 to 56 cm.
Depth to 2C horizons with sandy-skeletal materials: 50 to 90 cm.

Particle-size control section - Clay content: 20 to 35 percent.
Rock fragments: 15 to 30 percent, mainly gravel. Lithology of fragments is mixed.

A horizon
Value: 6 or 7 dry, 4 or 5 moist.
Chroma: 2 through 4, dry or moist.
Reaction: Moderately alkaline through very strongly alkaline (up to pH 9.6).

Btk or Bt horizons
Value: 5 through 7 dry; 3 through 6 moist.
Chroma: 2 through 4, dry or moist.
Texture: Gravelly clay loam, gravelly sandy clay loam or gravelly loam.
Rock fragments: 15 to 30 percent, mainly gravel.
Structure: Weak or moderate, fine or medium subangular blocky, and weak medium or coarse prismatic structure.
Consistence: Slightly hard or hard dry, very friable through very firm moist, slightly sticky or moderately sticky and slightly plastic or moderately plastic.
Reaction: Slightly alkaline through strongly alkaline.
Calcium carbonate equivalent: 1 to 15 percent.

Bqk horizon
Value: 6 through 8 dry, 4 through 6 moist.
Chroma: 2 through 4, dry or moist.
Texture: Gravelly sandy loam or gravelly sandy clay loam.
Rock fragments: 15 to 35 percent, mainly gravel.
Consistence: Soft to hard, very friable to firm, nonsticky or slightly sticky and nonplastic or slightly plastic; Most pedons have a matrix that is firm when moist along with a brittle manner of failure.
Silica features: Some pedons have zones of discontinuous cementation in strata and also have laminae of opaline silica.
Salinity (EC): 4 to 8 mmhos/cm.
Sodicity (SAR): 1 to 12.
Calcium carbonate equivalent: 2 to 20 percent.

2C horizon
Value: 6 through 8 dry, 3 through 5 moist.
Chroma: 2 through 4, dry or moist.
Texture: Very gravelly sand, very gravelly loamy sand, or extremely gravelly sand.
Rock fragments: 40 to 70 percent, mainly gravel with 0 to 5 percent cobbles in some pedons.
Consistence: Soft or slightly hard, very friable or friable, or is loose.
Salinity (EC): 4 to 8 mmhos/cm.
Sodicity (SAR): 13 to 30.
Other features: Some pedons have 20 to 65 percent discontinuous strong silica and carbonate cementation.

COMPETING SERIES: These are the Caudle, Nyala, Tocan, and Vigus series.

Caudle soils have no more than 5 percent rock fragments in the particle-size control section and do not have sandy, very gravelly, or extremely gravelly horizons in the lower part of the substratum. Nyala and Vigus soils have no more than 15 percent rock fragments in the particle-size control section and do not have sandy, very gravelly or extremely gravelly horizons within 100 cm of the soil surface. Tocan soils do not have identifiable secondary carbonates in the argillic horizon.

GEOGRAPHIC SETTING: Unsel soils are on fan remnants and fan skirts. They formed in alluvium derived dominantly from mixed rocks. Slopes are 0 to 30 percent. Elevations range from 1,073 to 2,140 meters. The climate is arid with cool, moist winters and warm, dry summers. The mean annual precipitation is 125 to 200 mm, the mean annual temperature is 9 to 13 degrees C, and the frost-free period is 100 to 130 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Belted and Izo soils. Belted soils are loamy, very shallow and shallow to duripans, and have argillic horizons. Izo soils are sandy-skeletal, very deep, and do not have argillic horizons.

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

USE AND VEGETATION: Unsel soils are used for rangeland and wildlife habitat. The vegetation is mainly Bailey's greasewood, shadscale, bud sagebrush, galleta, winterfat, and littleleaf horsebrush.

DISTRIBUTION AND EXTENT: Central Nevada. These soils are extensive with about 450,000 acres of the series mapped to date. MLRAs 28B and 29.

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

SERIES ESTABLISHED: Nye County (Big Smoky Valley Area), Nevada, 1972.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 10 cm (A horizon).
Argillic horizon - The zone from 10 to 25 cm (Btk1 and Btk2 horizons).
Identifiable secondary carbonates - The zone from 25 to 79 cm (Btk1, Btk2, and Bqk horizons).
Duric feature - The zone from 25 to 79 cm (Bqk horizon).
Particle-size control section - The zone from 10 to 25 cm (Btk1 and Btk2 horizons).

ADDITIONAL DATA: A pedon of Unsel has full characterization data by the Soil Survey Laboratory (SSL), Lincoln, NE, as soil survey sample number S87NV-023-003 (pedon # 87P0270).

National Cooperative Soil Survey
U.S.A.