LOCATION ZADVAR                  NV

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

ZADVAR SERIES

The Zadvar series consists of shallow to a duripan, well drained soils that formed in alluvium derived from volcanic rocks. Zadvar soils are on fan remnants. Slopes are 2 to 30 percent. The mean annual precipitation is about 230 mm and mean annual temperature is about 8 degrees C.

TAXONOMIC CLASS: Loamy, mixed, superactive, mesic, shallow Haploxeralfic Argidurids

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

A1--0 to 8 cm; pale brown (10YR 6/3) gravelly fine sandy loam, brown (10YR 4/3) moist; moderate medium platy structure; soft, very friable, slightly sticky and nonplastic; many fine through coarse vesicular pores; 15 percent gravel; moderately alkaline (pH 8.0); abrupt smooth boundary. (3 to 20 cm thick)

A2--8 to 15 cm; pale brown (10YR 6/3) gravelly sandy loam, brown (10YR 4/3) moist; weak thin platy structure; soft, very friable, slightly sticky and nonplastic; common fine roots; few fine vesicular and common fine tubular pores; 10 percent gravel and 5 percent cobbles; moderately alkaline (pH 8.0); clear smooth boundary. (0 to 15 cm thick)

Bt--15 to 28 cm; yellowish brown (10YR 5/4) gravelly clay loam, dark yellowish brown (10YR 4/4) moist; weak medium prismatic parting to strong fine subangular blocky structure; hard, friable, moderately sticky and moderately plastic; common fine and coarse roots; common fine tubular pores; common distinct clay films on faces of peds, lining pores, and bridging sand grains; 25 percent gravel and 5 percent cobbles; moderately alkaline (pH 8.3); clear wavy boundary. (10 to 25 cm thick)

Bqkm--28 to 71 cm; cemented material; matrix is strongly cemented by secondary carbonates and silica with discontinuous indurated laminae of silica; massive; brittle, nonsticky and nonplastic; few fine roots in pockets; violently effervescent; moderately alkaline (pH 8.4); clear smooth boundary. (10 to 46 cm thick)

Bqk--71 to 152 cm; light brownish gray (10YR 6/2) stratified extremely gravelly coarse sand to extremely gravelly sandy loam with discontinuous strong cementation; brown (10YR 4/3) moist; massive; soft to hard, very friable to brittle; nonsticky and nonplastic; few fine roots in pockets; many fine interstitial pores; carbonate and silica coating on rock fragments; 65 percent gravel; violently effervescent; moderately alkaline (pH 8.4).

TYPE LOCATION: Nye County, Nevada; between the south end of Stone Cabin Valley and the Kawich Range; about 2,000 feet north and 1,900 feet east of the southwest corner of section 2, T. 1 N., R. 48 E.; USGS Stinking Spring 7.5 minute topographic quadrangle; latitude 37 degrees 57 minutes 57 seconds N and longitude 116 degrees 34 minutes 26 seconds W; WGS84 Decimal Degrees 37.9659444 latitude, -116.5738889 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist in winter and spring, dry in summer and fall except for 10 to 20 days cumulative between July and October due to convection storms; aridic soil moisture regime that borders on xeric.
Mean annual soil temperature: 12 to 15 degrees C.
Ochric epipedon thickness: 3 to 20 cm.
Depth to duripan: 25 to 36 cm.

Particle-size control section - Clay content: Averages 18 to 27 percent.
Rock fragments: Averages 20 to 35 percent, mainly gravel. Lithology of fragments is volcanic rocks such as rhyolite.

A horizons
Value: 5 through 7 dry, 4 or 5 moist.
Chroma: 2 or 3, dry or moist.
Clay content: 8 to 18 percent.
Reaction: Slightly alkaline or moderately alkaline.
Effervescence: Noneffervescent through strongly effervescent.

Bt horizon
Value: 5 or 6 dry, 4 or 5 moist.
Chroma: 3 or 4, dry or moist.
Texture: Gravelly clay loam, sandy clay loam, or gravelly sandy clay loam.
Clay content: 27 to 35 percent; some pedons may have more than 35 percent.
Rock fragments: 10 to 30 percent, mainly gravel.
Structure: Prismatic or subangular blocky.
Consistence: Slightly hard or hard.
Reaction: Slightly alkaline or moderately alkaline.
Effervescence: Usually noneffervescent, but some pedons may be slightly effervescent or strongly effervescent in the lower part.

Bqk horizon
Chroma: 2 or 3, dry or moist.
Texture: Stratified very gravelly coarse sand to extremely gravelly sandy loam.
Clay content: 5 to 10 percent.
Rock fragments: 35 to 65 percent, mainly gravel.
Consistence: Soft to hard, very friable to brittle.
Reaction: Moderately alkaline or strongly alkaline.
Effervescence: Strongly effervescent or violently effervescent.
Calcium carbonate equivalent: 15 to 30 percent.
Other features: Some pedons have Bqk horizons above the hardpan with very gravelly to gravelly sandy loam or loam texture. This is a result of degradation of the duripan.

COMPETING SERIES: These are the Acana, Diawell, Mickey, Minu, and Muni series.

Acana soils have mean annual soil temperature of 8 to 11 degrees C. Diawell soils have Bkq horizons above the duripan and have duripans at depths of 36 to 50 cm from the soil surface. Mickey soils average 27 to 35 percent clay in the particle-size control section and have duripans at depths of 36 to 50 cm from the soil surface. Minu soils have secondary carbonates in the lower part of the argillic horizon and have mean annual soil temperature of 8 to 12 degrees C. Muni soils have duripans at depths of 36 to 50 cm from the soil surface and average less than 15 percent rock fragments in the particle-size control section.

GEOGRAPHIC SETTING: Zadvar soils are on fan remnants. These soils formed in alluvium derived mainly from volcanic rocks. Slopes are 2 to 30 percent. Elevations range from 1,300 to 2,387 meters. The mean annual precipitation is 200 to 250 mm, the mean annual temperature is 9 to 12 degrees C, and the frost-free period is 100 to 130 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bellehelen, Chuckridge, Handpah, Stewval, and Veet soils. Bellehelen and Stewval soils are shallow to lithic contacts. Chuckridge soils have indurated duripans. Handpah soils have indurated duripans which are 36 to 50 cm from the soil surface. Veet soils are loamy-skeletal, very deep, have cambic horizons, and do not have duripans.

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

USE AND VEGETATION: Zadvar soils are used for rangeland and wildlife habitat. The present vegetation is mainly black sagebrush, galleta, Indian ricegrass, and bottlebrush squirreltail.

DISTRIBUTION AND EXTENT: South-central Nevada. These soils are extensive with about 200,000 acres of the series mapped to date. MLRA 29.

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

SERIES ESTABLISHED: Esmeralda County, Nevada, 1984.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 15 cm (A1 and A2 horizons).
Argillic horizon - The zone from 15 to 28 cm (Bt horizon).
Duripan - The zone from 28 to 71 cm (Bqkm horizon).
Identifiable secondary carbonates - The zone from 28 to 152 cm (Bqkm and Bqk horizons).
Particle-size control section - The zone from soil surface to 28 cm (A1, A2, and Bt horizons).

ADDITIONAL DATA: A Zadvar pedon from Nye County that is slightly outside the range of the series is sampled for full characterization by the Soil Survey Laboratory (SSL), Lincoln, NE, as soil survey sample number S87NV-023-002 (pedon # 87P0269).

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National Cooperative Soil Survey
U.S.A.