LOCATION DEWRUST NV

Established Series
Rev. DJM/RLB/JBF
06/2016

DEWRUST SERIES

The Dewrust series consists of moderately deep over a duripan, well drained soils that formed in alluvium derived from volcanic rocks with a component of volcanic ash. The Dewrust soils are on fan piedmonts. Slopes are 4 to 8 percent. The mean annual precipitation is about 230 mm and the mean annual temperature is about 13 degrees C.

TAXONOMIC CLASS: Fine, smectitic, mesic Xeric Argidurids

TYPICAL PEDON: Dewrust very gravelly sandy loam--rangeland. (Colors are for dry soil unless otherwise noted.) The surface is partially covered with 5 percent cobbles and 35 percent gravel.

A1--0 to 8 cm; yellowish brown (10YR 5/4) very gravelly sandy loam, dark brown (7.5YR 3/4) moist; strong thin and medium platy structure; soft, very friable, slightly sticky and slightly plastic; few very fine and fine roots; common very fine tubular pores; 5 percent cobbles and 35 percent gravel; neutral (pH 7.0); clear smooth boundary. (5 to 10 cm thick)

A2--8 to 15 cm; brown (10YR 5/3) gravelly loam, dark brown (7.5YR 3/4) moist; weak thin platy structure; soft, very friable, slightly sticky and slightly plastic; many very fine, fine and medium and few coarse roots; common very fine and fine and few medium tubular pores; 5 percent cobbles and 10 percent gravel; slightly alkaline (pH 7.6); abrupt wavy boundary. (5 to 10 cm thick)

Bt1--15 to 28 cm; brown (7.5YR 4/4) gravelly clay loam, dark brown (7.5YR 3/4) moist; strong coarse prismatic structure; slightly hard, friable, moderately sticky and moderately plastic; few very fine, fine and medium roots; few very fine tubular pores; few faint clay films lining pores; 5 percent cobbles and 10 percent gravel; slightly alkaline (pH 7.6); abrupt wavy boundary. (10 to 20 cm thick)

Bt2--28 to 43 cm brown (7.5YR 4/4) gravelly clay loam, dark brown (7.5YR 3/4) moist; strong coarse prismatic structure; hard firm, very sticky and very plastic; few very fine and fine roots; few fine tubular pores; common faint clay films lining pores; prominent continuous pressure faces; 25 percent gravel; slightly alkaline (pH 7.6) abrupt wavy boundary. (13 to 25 cm thick)

Bt3--43 to 58 cm; brown (7.5YR 4/4) gravelly clay, dark brown (7.5YR 3/4) moist; moderate very coarse prismatic structure; hard, firm, very sticky and very plastic; few very fine and fine roots; few fine tubular pores; common faint clay films lining pores; prominent continuous pressure faces; 20 percent gravel; slightly alkaline (pH 7.8); clear wavy boundary. (13 to 20 cm thick)

Btk--58 to 76 cm; strong brown (7.5YR 5/6) very gravelly clay, brown (7.5YR 4/4) moist; moderate fine and medium subangular blocky structure; hard, firm, very sticky and very plastic; few very fine and fine roots; common fine tubular pores; common faint clay films lining pores; prominent continuous pressure faces; strongly effervescent few thin carbonate coating and pendants on undersides of rock fragments; 15 percent cobbles and 35 percent gravel; slightly alkaline (pH 7.6); abrupt wavy boundary. (8 to 23 cm thick)

Bqkm--76 cm; very pale brown (10YR 8/2) indurated duripan, very pale brown (10YR 7/3) moist; massive; extremely hard, extremely firm, brittle; continuous 4 to 6 mm thick horizontal silica laminae; violently effervescent; very strongly alkaline (pH 9.2).

TYPE LOCATION: Lincoln County, Nevada; approximately 3 miles west of Elgin, 150 feet south and 3000 feet east from the northwest corner of Section 15, T. 7 S., R. 66 E.; USGS Elgin 7.5 minute topographic quadrangle; latitude 37 degrees 20 minutes 50 seconds N and longitude 114 degrees 35 minutes 07 seconds W; WGS84 Decimal Degrees 37.3472222 latitude, -114.5852778 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually dry, 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 bordering on xeric.
Mean annual soil temperature: 13 to 14 degrees C.
Depth to carbonates: 46 to 76 cm.
Depth to duripan: 50 to 100 cm.

Particle-size control section - Clay content: Averages 35 to 50 percent.
Rock fragments: Averages 15 to 25 percent.

A horizon
Hue: 10YR or 7.5YR.
Value: 5 or 6 dry.
Chroma: 3 or 4.
Reaction: Neutral or slightly alkaline.

Bt1 horizon
Hue: 10YR or 7.5YR.
Value: 3 or 4 moist.
Chroma: 3 or 4 moist.
Clay content: 27 to 35 percent, there is less than 15 percent increase in a vertical depth of 2.5 cm.
Texture: Clay loam or gravelly clay loam.
Rock fragments: 10 to 20 percent.
Reaction: Slightly alkaline or moderately alkaline.

Bt2 and Bt3 horizons
Hue: 10YR or 7.5YR.
Value: 4 or 5 dry.
Clay content: 35 to 60 percent.
Texture: Clay, gravelly clay, or gravelly clay loam.
Rock fragments: 10 to 20 percent, mainly gravel and cobbles
Structure: Coarse or very coarse prismatic.
Reaction: Slightly alkaline or moderately alkaline.
Other features: Many to continuous pressure faces.

Btk horizons
Hue: 10YR or 7.5YR
Value: 4 or 5 dry.
Chroma: 5 or 6 dry, 3 or 4 moist.
Clay content: 50 to 60 percent.
Texture: Gravelly clay or very gravelly clay.
Rock fragments: 25 to 50 percent, mainly gravel and cobbles.
Structure: Subangular blocky or prismatic.
Consistence: Hard or very hard.
Reaction: slightly alkaline or moderately alkaline
Secondary carbonates: Thin to thick carbonate coats on undersides of rock fragments throughout the Btk.

COMPETING SERIES: These are the Goosel and Hunnton soils.

Goosel soils are underlain by bedrock at moderate depth, and contain less than 15 percent coarse fragment in the particle size control section. Hunnton soils are dry in the moisture control section from July through October and have average soil temperatures cooler than 13 degrees C.

GEOGRAPHIC SETTING: Dewrust soils are on fan piedmonts. These soils formed in alluvium derived from mixed volcanic rocks, dominantly rhyolitic tuffs. Slopes are 4 to 8 percent. Elevations are 1,375 to 1,590 meters. The climate is semi-arid with cool moist winters and warm intermittently moist summers. The mean annual precipitation is 200 to 250 mm, mean annual temperature is 13 to 14 degrees C, and the frost- free season is 140 to 180 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Veet soils. Veet soils lack an argillic horizon and a duripan.

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

USE AND VEGETATION: Rangeland and wildlife habitat. The present vegetation is mainly blackbrush, banana yucca, Mexican cliffrose and threeawn.

DISTRIBUTION AND EXTENT: Southeastern Nevada. Dewrust soils are not extensive. MLRA 29.

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

SERIES ESTABLISHED: Lincoln County, Nevada, South Part, 1992.

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 76 cm (Bt1, Bt2 Bt3 and Btk horizons).
Duripan - Indurated layer below 76 cm (Bqkm horizon).
Xeric intergrades - Meets organic carbon requirement for xeric.
Particle-size control section - The zone from 15 to 65 cm (Bt1, Bt2, Bt3 and upper part of the Btk horizon).

ADDITIONAL DATA: Characterization data is available for sample 586NV- 017-007.

National Cooperative Soil Survey
U.S.A.