LOCATION ZADVAR             NV
Established Series
Rev. JBF-WED-RLB-JVC
03/2003

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 9 inches and mean annual temperature is about 52 degrees F.

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 3 inches; 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 pebbles; moderately alkaline (pH 8.0); abrupt smooth boundary. (1 to 8 inches thick)

A2--3 to 6 inches; 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 pebbles and 5 percent cobbles; moderately alkaline (pH 8.0); clear smooth boundary. (0 to 6 inches thick)

Bt--6 to 11 inches; 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 pebbles and 5 percent cobbles; moderately alkaline (pH 8.3); clear wavy boundary. (4 to 10 inches thick)

Bqkm--11 to 28 inches; 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. (4 to 18 inches thick)

Bqk--28 to 60 inches; 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; lime and silica coating on rock fragments; 65 percent pebbles; 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; 37 degrees 57 minutes 57 seconds north latitude and 116 degrees 34 minutes 22 seconds west longitude, NAD27.

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 moisture regime that borders on xeric.

Mean annual soil temperature - 53 to 59 degrees F.

Ochric epipedon thickness - 1 to 8 inches.

Depth to duripan - 10 to 14 inches.

Particle-size control section - Clay content: Averages 18 to 27 percent; Rock fragments: Averages 20 to 35 percent, mainly pebbles. Lithology of fragments are 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 to 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 pebbles.
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 to 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 pebbles.
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 47 to 52 degrees F. Diawell soils have Bkq horizons above the duripan and have duripans at depths of 14 to 20 inches from the soil surface. Mickey soils average 27 to 35 percent clay in the particle-size control section and have duripans at depths of 14 to 20 inches from the soil surface. Minu soils have secondary carbonates in the lower part of the argillic horizon and have mean annual soil temperature of 47 to 53 degrees F. Muni soils have duripans at depths of 14 to 20 inches 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 5,200 to 7,500 feet. The mean annual precipitation is 8 to 10 inches, the mean annual temperature is 48 to 54 degrees F., 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 14 to 20 inches from the soil surface. Veet soils are loamy-skeletal, very deep, have cambic horizons, and do not have duripans.

DRAINAGE AND PERMEABILITY: Well drained; very high surface runoff; moderately slow permeability.

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 OFFICE RESPONSIBLE: Reno, Nevada.

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 6 inches (A1 and A2 horizons).

Argillic horizon - The zone from 6 to 11 inches (Bt horizon).

Duripan - The zone from 11 to 28 inches (Bqkm horizon).

Identifiable secondary carbonates - The zone from 11 to 60 inches (Bqkm and Bqk horizons).

Particle-size control section - The zone from soil surface to 11 inches (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).


National Cooperative Soil Survey
U.S.A.