LOCATION DEDAS                   NV

Established Series
Rev. JR/RLB/WED
04/2015

DEDAS SERIES

The Dedas series consists of shallow over a duripan well drained soils underlain by bedrock. Dedas soils are on summits and sideslopes of rock pediment remnants. Dedas soils formed in residuum from tuff overlain by mixed pedisediments. Slopes are 4 to 50 percent. The mean annual precipitation is about 7 inches and the mean annual temperature is about 60 degrees F.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, thermic, shallow Typic Argidurids

TYPICAL PEDON: Dedas very gravelly sandy loam, rangeland. (Colors are for dry soil unless otherwise noted.) The soil surface is partially covered with 40 percent pebbles, 20 percent cobbles and 1 percent stones.

A--0 to 3 inches; pale brown (10YR 6/3) very gravelly sandy loam, dark brown (10YR 4/3) moist; weak fine platy structure; soft, very friable, nonsticky and slightly plastic; common very fine and fine roots; common very fine and fine tubular pores; 40 percent pebbles, 2 percent cobbles; violently effervescent; moderately alkaline (pH 8.4); clear smooth boundary. (2 to 4 inches thick)

Bt--3 to 8 inches; very pale brown (10YR 7/3) very gravelly sandy loam, yellowish brown (10YR 5/4) moist; moderate medium and coarse subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine and fine, common medium roots; many fine and few coarse tubular pores; few thin clay films on pebbles; 45 percent pebbles approximately half which are pan fragments; violently effervescent; moderately alkaline (pH 8.4); clear smooth boundary. (3 to 10 inches thick)

Btk--8 to 15 inches; pale brown (10YR 6/3) very gravelly sandy loam, dark yellowish brown (10YR 4/4) moist; moderate medium and coarse subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; few very fine roots; common fine and medium tubular pores; few thin clay films on pebbles, 40 percent pebbles, half of which are pan fragments; common faint lime patches on pebbles; violently effervescent; moderately alkaline (pH 8.4); abrupt wavy boundary. (5 to 10 inches thick)

Bqkm--15 to 17 inches; very pale brown (10YR 8/3) indurated duripan, very pale brown (10YR 7/3) moist; continuous laminar cap and alternating horizontal bands of partially degraded tuff, with continuous thin silica laminae; violently effervescent; abrupt smooth boundary (2 to 8 inches thick)

R--17 inches; white (10YR 8/1) unweathered tuff bedrock.

TYPE LOCATION: Nye County, Nevada, about 6 miles northeast of Beatty, 2,110 feet north and 790 feet east of the southwest corner of section 9, T. 11 S., R. 48 E.

RANGE IN CHARACTERISTICS:

Soil moisture - Usually dry, moist in some part of the moisture control section for short periods during late fall through early spring, and for intermittently for 10 to 20 days cumulative from July through October, following summer convection storms.

Soil temperature - 59 to 63 degrees F.

Depth to duripan - 14 to 20 inches.

Depth to bedrock - 16 to 24 inches.

Other features - Some pedons have thin Bk horizons below the argillic horizons.


Control section - Percent clay: 10 to 18 percent.

Rock fragments - 35 to 60 percent pebbles.


A horizon - Value: 5 or 6 dry, 4 or 5 moist.

Chroma: 3 or 4, moist or dry.


Bt horizon - Value: 6 or 7 dry, 4 through 6 moist.

Chroma: 3 or 4.

Texture: Very gravelly loam, very gravelly sandy loam, or very gravelly coarse sandy loam.

Clay content: 10 to 18 percent.

Rock fragments: 35 to 60 percent pebbles.

Structure: Subangular blocky or massive.

Consistence: Very friable or friable moist.


Bqkm horizon - Value: 6 through 8 moist or dry.

Chroma: 2 or 3.

Consistence: Very hard or extremely hard dry, very firm or extremely firm moist.

Other features: 1 to 4 millimeters thick continuous laminar cap.

Rupture resistance: Very strongly cemented to indurated.

COMPETING SERIES: This is the Peloncillo (AZ) soils. Peloncillo soils lack bedrock within a depth of 60 inches.

GEOGRAPHIC SETTING: Dedas soils are on summits and side slopes of rock pediment remnants. These soils formed in mixed pedisediments over residuum of rhyolitic ash-fall tuffs. Slopes are 4 to 50 percent. Elevations are 3,200 to 4,700 feet. The climate is hot and dry in the summer with infrequent convection storms between May and October. The winters are cool with common rain showers between December and April. The mean annual precipitation is about 6 to 9 inches. The mean annual temperature is about 57 to 61 degrees F. The frost- free season is about 190 to 210 days.

GEOGRAPHICALLY ASSOCIATED SOILS: This is the Orwash series. Orwash soils lack argillic horizons.

DRAINAGE AND PERMEABILITY: Well drained, medium runoff; moderately rapid permeability.

USE AND VEGETATION: Rangeland and wildlife habitat. The present vegetation is mainly blackbrush with shadscale, cheeseweed burrobrush, ephedra, spiny menodora, winterfat, creosotebush and Indian ricegrass.

DISTRIBUTION AND EXTENT: Southern Nye County, Nevada. These soils are not extensive. MLRA 30.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: PHOENIX, ARIZONA

SERIES PROPOSED: Nye County (Southwest Part), Nevada, 1982. The name is coined.

REMARKS: Diagnostic horizons and features recognized in this pedon are:

Argillic horizon - The zone from about 3 to 15 inches (Bt and Btk horizons).

Duripan - The zone from about 15 to 17 inches (Bqkm horizon).

Lithic contact - The boundary between the duripan and bedrock at about 17 inches.

Particle size control section - The zone from about 3 to 15 inches (Bt and Btk horizons).

Responsibility for this series was transferred from Davis to Phoenix 4/2015. The last revision to the series was 11/2001. ET

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National Cooperative Soil Survey
U.S.A.