LOCATION WODAVAR            NV
Established Series
Rev. LJL/RLB/TM
02/2006

WODAVAR SERIES


The Wodavar series consists of shallow to a hardpan, well drained soils that formed in residuum from lacustrine deposits. Wodavar soils are on lake terraces and alluvial flats. Slope ranges from 2 to 8 percent. The mean annual precipitation is about 5 inches and the mean annual air temperature is about 60 degrees F.

TAXONOMIC CLASS: Loamy-skeletal, carbonatic, thermic, shallow Calcic Petrocalcids

TYPICAL PEDON: Wodavar extremely gravelly fine sandy loam, rangeand wildlife habitat. (Colors are for dry soil unless otherwise noted.) The soil surface is covered by approximately 65 percent pebbles consisting of pan fragments.

A--0 to 3 inches; very pale brown (10YR 7/3) extremely gravelly fine sandy loam, yellowish brown (10YR 5/4) moist; moderate medium and thick platy structure; slightly hard, very friable, slightly sticky and slightly plastic; few very fine roots; many very fine and few fine vesicular and interstitial pores; 65 percent pebbles consisting of pan fragments; violently effervescent; moderately alkaline (pH 8.4); clear smooth boundary. (2 to 6 inches thick)

Bk--3 to 16 inches; pale brown (10YR 6/3) very gravelly sandy loam, yellowish brown (10YR 5/4) moist; weak medium subangular blocky structure; slightly hard, very friable, nonsticky and slightly plastic; many very fine, few fine and medium roots; common very fine and few fine interstitial pores; 40 percent pebbles consisting of calcium carbonate nodules; violently effervescent; very strongly alkaline (pH 9.2); clear wavy boundary. (6 to 16 inches thick)

Bkm1--16 to 22 inches; white (10YR 8/1) very strongly cemented petrocalcic horizon, very pale brown (10YR 7/3) moist; moderate very thick platy structure; very rigid, rigid, brittle; common very fine and few fine and medium roots in fractures; common very fine and few fine tubular pores; violently effervescent; strongly alkaline (pH 8.8); clear wavy boundary. (0 to 8 inches thick)

Bkm2--22 to 33 inches; white (10YR 8/1) continuously indurated petrocalcic horizon, pale brown (10YR 6/3) moist; massive; very rigid,very rigid, brittle; few very fine and fine tubular pores; violently effervescent; strongly alkaline (pH 8.6); clear wavy boundary. (8 to 24 inches thick)

Bk--33 to 60 inches; white (10YR 8/1) extremely gravelly loam, pale brown (10YR 6/3) moist; massive; moderately hard, friable, slightly sticky and slightly plastic; few very fine and fine tubular pores; 60 percent pebbles consisting of strongly cemented calcium carbonate nodules; violently effervescent; strongly alkaline (pH 8.6).

TYPE LOCATION: Clark County, Nevada; approximately 0.6 miles east of Stump Spring in the southeast end of Pahrump Valley; about 150 feet south and 125 feet east of the northeast corner of section 5, T. 23 S., R. 55 E.; USGS Stump Spring, NV 7.5 minute topographic quadrangle; 35 degrees, 59 minutes, 3 seconds north latitude and 115 degrees, 48 minutes, 55 seconds west longitude; UTM 11, 606799e, 3982848n; NAD 83.

RANGE IN CHARACTERISTICS:

Soil moisture - Usually dry, moist in some part for short periods during winter and early spring, typic-aridic moisture regime. The ratio of soil moisture utalized for evapotranspiration between summer and winter is about 0.4:1, typical of the Mojave Desert.

Soil temperature - 59 to 65 degrees F.

Depth to calcic horizon - 2 to 6 inches.

Depth to hardpan - 10 to 20 inches.

Control section - Percent clay: 8 to 16 percent.
Rock fragments: Averages 35 to 60 percent, mainly calcium carbonate nodules and pan fragments.

Bk horizon - Rock fragments: 35 to 60 percent.

Calcium carbonate equivalence in the fine earth fraction: 25 to 40 percent 40 to 80 percent of the less than 20 millimeter fraction.

Secondary carbonates: 30 to 60 percent identifiable secondary calcium carbonate as nodules, concretion or soft masses.

Other features: Secondary gypsum as few or common fine segregations and crystals are in some pedons.

Bkm horizons - Rupture resistance: Indurated or very strongly cemented

Bk horizon - Clay content: 10 to 18 percent.

Rock fragments: 35 to 65 percent, mainly calcium carbonate nodules.

Calcium carbonate equivalence in the fine earth fraction: 40 to 60 percent.

COMPETING SERIES: These are the Ferrogold (NV), Infantry (NM), Neso (NM), Orrubo (T AZ), Paisano (TX), Philder (NM), Sutherland (AZ), Tencee (NM) and Wechech (NV) series. Ferrogold soils have rock fragments that are limestone or dolomite. Infantry soils have Bk horizons with 35 to 60 percent cobbles and have significant summer moisture, typical of the Chihuahuan desert. Neso soils receive significant summer moisture, typical of the Chihuahuan desert and are in a 12 to 15 inch precipitation zone. Orrubo soils have Cr horizons below the hardpan at depths between 17 and 30 inches. Paisano soils receive significant summer moisture, typical of the Chihuahuan desert and depth to hardpan is less than 14 inches. Philder soils have aridic soil moisture regimes that border on ustic and have 18 to 25 percent clay. Sutherland soils have an ustic aridic soil moisture regime. Tencee soils receive significant summer moisture, typical of the Chihuahuan and Sonoran deserts. Wechech soils are less than 14 inches to the hardpan, and receive additional summer moisture.

GEOGRAPHIC SETTING: Wodavar soils are on alluvial flats and lake terraces. These soils formed in residuum from lacustrine deposits. Slope ranges from 2 to 8 percent. Elevations are 2,600 to 3,000 feet. The climate is warm and arid with hot dry summers and cool winters, typical of the Mojave Desert. The mean annual precipitation is 3 to 7 inches; mean annual temperature is 58 to 64 degrees F., and the frost-free season is 200 to 220 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Tanazza and Tencee soils. Tanazza soils lack petrocalcic horizons and Tencee soils are in a loamy-skeletal family.

DRAINAGE AND PERMEABILITY: Well drained, very high runoff; moderate permeability.

USE AND VEGETATION: These soils are used for rangeland and wildlife habitat. The vegetation is mainly shadscale and desertholly.

DISTRIBUTION AND EXTENT: Mojave Desert of southern Nevada. Wodavar soils are not extensive. MLRA 30.

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

SERIES ESTABLISHED: Nye County, Nevada, Southwest Part, 1994.

REMARKS: These soils were previously called Woda Variant in Nye County and Sequite in Clark County. The type location was moved to adjoining Clark County and the concept redefined after further investigations in 1996.

Diagnostic horizons and features recognized in this pedon are:

Ochric epipedon - 0 to 3 inches (A horizon)

Calcic horizon - 3 to 16 inches (Bk horizon)

Petrocalcic horizon 16 to 33 inches (Bkqm1 and Bkqm2 horizons)

Particle-size control section - 10 to 16 inches (Part of the Bk horizon).


National Cooperative Soil Survey
U.S.A.