LOCATION DEVADA NV+CA OR

Established Series
Rev. DMC-RLB-JVC-JBF
02/2016

DEVADA SERIES

The Devada series consists of shallow, well drained soils that formed in residuum derived from volcanic rocks with additions of loess and volcanic ash. Devada soils are on plateaus, mountains, and hills. Slopes are 0 to 50 percent. The mean annual precipitation is about 300 mm and the mean annual temperature is about 8 degrees C.

TAXONOMIC CLASS: Clayey, smectitic, mesic Aridic Lithic Argixerolls

TYPICAL PEDON: Devada very cobbly loam--rangeland. (Colors are for dry soil unless otherwise noted.) The soil surface is covered with 2 percent stones, 30 percent cobbles, and 35 percent gravel.

A1--0 to 3 cm; grayish brown (10YR 5/2) very cobbly loam, very dark grayish brown (10YR 3/2) moist; massive; soft, very friable, nonsticky and nonplastic; few very fine roots; many very fine interstitial pores; 25 percent gravel and 20 percent cobbles, slightly acid (pH 6.2); abrupt smooth boundary. (3 to 10 cm thick)

A2--3 to 10 cm; grayish brown (10YR 5/2) very cobbly loam, very dark grayish brown (10YR 3/2) moist; moderate coarse subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine and common fine roots; many very fine interstitial pores; 25 percent gravel and 20 percent cobbles; slightly acid (pH 6.4); abrupt smooth boundary. (5 to 15 cm thick)

Bt1--10 to 13 cm; brown (10YR 5/3) clay loam, very dark grayish brown (10YR 3/2) moist; moderate fine subangular blocky structure; slightly hard, very friable, very sticky and moderately plastic; few fine roots; very few fine tubular pores; common distinct clay films on faces of peds; neutral (pH 6.8); abrupt smooth boundary. (0 to 30 cm thick)

Bt2--13 to 33 cm; brown (10YR 4/3) gravelly clay, dark brown (10YR 3/3) moist; strong medium and coarse angular blocky structure; hard, firm, very sticky and very plastic; few fine roots; few fine tubular pores; many prominent clay films on faces of peds and lining pores; 15 percent gravel; neutral (pH 6.8); very abrupt irregular boundary. (5 to 25 cm thick)

R--33 cm; rhyolite.

TYPE LOCATION: Douglas County, Nevada; about 2 miles south-southeast of Holbrook Junction on Wild Oat Mountain; approximately 2,000 feet east and 1,000 feet north of the southwest corner of section 20, T. 10 N., R. 22 E; USGS Topaz Lake 7.5 minute topographic quadrangle; latitude 38 degrees 42 minutes 40 seconds N and longitude 119 degrees 32 minutes 43 seconds W; WGS84 Decimal Degrees 38.7111111 latitude, -119.5452778 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist in winter and spring, dry in summer through late fall; aridic soil moisture regime that borders on xeric.
Mean annual soil temperature: 8 to 12 degrees C.
Mollic epipedon thickness: 18 to 50 cm; includes all or part of the argillic horizon.
Depth to base of argillic horizon: 30 to 50 cm.
Depth to bedrock: 30 to 50 cm to a lithic contact.
Other features: Some pedons have thin E or E/B horizons.

Particle-size control section - Clay content: 40 to 60 percent.
Rock fragments: 0 to 30 percent, mainly gravel. Lithology of fragments are volcanic rocks such as rhyolite, andesite, or basalt.

A horizons
Value: 4 or 5 dry, 2 or 3 moist. Some pedons have a thin surface layer with value of 6 dry, but when the upper 18 cm are mixed, value is less than 5.5 dry.
Chroma: 2 or 3, dry or moist.
Reaction: Slightly acid through slightly alkaline.
Organic matter content: 1 to 3 percent.

Bt horizons
Hue: 5YR through 10YR.
Value: 4 through 6 dry, 3 or 4 moist.
Chroma: 2 through 4, dry or moist.
Texture: Clay or gravelly clay, commonly with thin subhorizons of clay loam.
Structure: Prismatic, angular blocky, subangular blocky.
Consistence: Slightly hard to very hard, dry; moderately sticky to very sticky, wet.
Reaction: Neutral or slightly alkaline.
Organic matter content: 0.5 to 2 percent.
Other features: Some pedons have thin silica coats on peds and rock fragments in the lower part of the Bt horizon.

COMPETING SERIES: These are the Bidrim, Brezniak, Cullius, Dunnlake, and Wylo series.

Bidrim soils have A horizons with 3 to 8 percent organic matter. Brezniak soils are 18 to 30 cm deep to bedrock. Cullius soils have 10 to 30 percent volcanic glass in the A horizon and do not have abrupt boundaries between the A and Bt horizons. Dunnlake soils do not have abrupt boundaries between the A and Bt horizons. Wylo soils have mean annual soil temperature of 12 to 15 degrees C. and do not have abrupt boundaries between the A and Bt horizons.

GEOGRAPHIC SETTING: Devada soils are on plateaus, mountains, and hills. They typically occur on summit, shoulder, and footslope positions. These soils formed in residuum derived from volcanic rock with additions of loess and volcanic ash. Slopes are 0 to 50 percent. Elevations range from 1,340 to 2,290 meters. The mean annual precipitation is 250 to 360 mm, the mean annual temperature is 7 to 9 degrees C, and the frost-free period is 60 to 110 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Cagle, Drit, Duco, Koontz, Nosrac, and Roloc soils. Cagle and Nosrac soils are deep. Drit soils are deep and lack an argillic horizon. Duco, Koontz, and Roloc soils are loamy-skeletal.

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

USE AND VEGETATION: Devada soils are used for rangeland and wildlife habitat. The vegetation is mainly low sagebrush, bottlebrush squirreltail, Sandberg bluegrass, and Thurber needlegrass. Scattered Utah juniper or western juniper occur in some areas in rangeland plant communities.

DISTRIBUTION AND EXTENT: Northwestern Nevada, northeastern California, and southcentral Oregon. These soils are extensive with about 432,000 acres of the series mapped to date. The original series concept is in MLRA 26, the main acreage is in MLRA 23, and other acreage occurs in MLRAs 21, 24, and 25.

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

SERIES ESTABLISHED: Douglas County Area, Nevada, 1981.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 33 cm (A1, A2, Bt1, and Bt2 horizons).
Argillic horizon - The zone from 20 to 33 cm (Bt1 and Bt2 horizons).
Lithic contact - The boundary at 33 cm to underlying hard, unweathered bedrock (R layer).
Particle-size control section - The zone from the soil surface to 33 cm (A1, A2, Bt1, and Bt2 horizons).

Classification was updated to 11th edition on 07/2011 changed from Lithic Argixerolls to Aridic Lithic Argixerolls

ADDITIONAL DATA: Several pedons of Devada have full characterization data by the Soil Survey Laboratory (SSL), Lincoln, NE, as soil survey sample numbers S86NV-013-301 (pedon # 86P0764), S86NV-031-006 (pedon # 86P0908), and S01NV-031-007 (pedon # 02N0109).
User Pedon ID: 2002NV0052035.

National Cooperative Soil Survey
U.S.A.