LOCATION GOCHEA                  NV+OR

Established Series
Rev. DNC/PWB/RLB/JBF
06/2016

GOCHEA SERIES

The Gochea series consists of very deep, well drained soils that formed in alluvium derived from mixed rocks and colluvium derived from weathered tuffs, basalt, rhyolite, andesite, and conglomerate with a component of loess. The Gochea soils are on fan piedmont remnants and stream terraces. Slopes are 2 to 30 percent. The mean annual precipitation is about 300 mm and the mean annual temperature is about 7 degrees C.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Argiduridic Argixerolls

TYPICAL PEDON: Gochea loam--rangeland. (Colors are for dry soil unless otherwise noted.)

A1--0 to 8 cm; grayish brown (10YR 5/2) loam, very dark grayish brown (10YR 3/2) moist; weak thick platy structure; soft, very friable, slightly sticky and slightly plastic; many fine and very fine roots; many fine and very fine vesicular and interstitial pores; neutral (pH 7.2); abrupt smooth boundary.

A2--8 to 18 cm; brown (10YR 5/3) loam, very dark grayish brown (10YR 3/2) moist; moderate fine and medium granular structure; soft, very friable, moderately sticky and moderately plastic; many fine and very fine roots; many fine and very fine interstitial pores; slightly alkaline (pH 7.4); clear smooth boundary. (combined thickness of A horizons is 10 to 33 cm)

Bt1--18 to 30 cm; brown (10YR 5/3) gravelly clay loam, dark brown (10YR 3/3) moist; moderate medium subangular blocky structure; slightly hard, friable, moderately sticky and moderately plastic; many fine and very fine roots; common fine interstitial pores; few faint clay films on faces of peds and lining pores; 20 percent gravel; slightly alkaline (pH 7.6); clear wavy boundary. (10 to 23 cm thick)

Bt2--30 to 53 cm; light yellowish brown (10YR 6/4) gravelly clay loam, brown (10YR 4/3) moist; strong medium subangular blocky structure; hard, friable, moderately sticky and moderately plastic; common fine roots; common fine interstitial and tubular pores; many distinct clay films on faces of ped and lining pores; 20 percent gravel; slightly alkaline (pH 7.8); gradual wavy boundary. (13 to 38 cm thick)

Bq1--53 to 104 cm; light yellowish brown (10YR 6/4) sandy loam, brown (10YR 4/3) moist; moderate medium subangular blocky structure; hard, firm, slightly sticky and slightly plastic; common fine roots; many very fine tubular pores; 40 percent durinodes; slightly alkaline (pH 7.6); gradual wavy boundary. (30 to 70 cm thick)

2Bq2--104 to 150 cm; light yellowish brown (10YR 6/4) extremely gravelly sand, variegated sand grains; yellowish brown (10YR 5/4) moist; massive; slightly hard, very friable, nonsticky and nonplastic; many medium and coarse interstitial pores; about 70 percent weak discontinuous silica cementation; 70 percent gravel; slightly alkaline (pH 7.8)

TYPE LOCATION: Elko County, Nevada; approximately 17 miles east of North Fork, about 2,200 feet west and 2,200 feet north of the southeast corner of section 1, T. 41 N., R. 57 E.; USGS Stag Mountain 7.5 minute topographic quadrangle; latitude 41 degrees 28 minutes 22 seconds N and longitude 115 degrees 29 minutes 15 seconds W; WGS84 Decimal Degrees 41.4727778 latitude, -115.4875000 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually dry; moist winter and spring, dry mid June through October; aridic soil moisture regime bordering on xeric.
Mean annual soil temperature: 6 to 8 degrees C.
Mollic epipedon thickness: 25 to 38 cm which commonly includes the upper part of the argillic horizon.
Depth to Bq horizon: 46 to 64 cm.
Other features: A lithologic discontinuity (2Bq, 2Bk, or 2C) is in most pedons between 100 and 150 cm.

Particle-size control Section - Clay content: Averages 25 to 35 percent.
Rock fragment: 5 to 35 percent, mainly gravel.

A horizon
Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 2 or 3.
Reaction: Neutral or slightly alkaline.

Bt horizon
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 2 through 4.
Texture: Clay loam or sandy clay loam.
Clay content: 25 to 35 percent.
Rock fragments: 5 to 35 percent, mainly gravel.
Structure: Subangular or angular blocky or prismatic.
Reaction: Neutral or slightly alkaline.
Other features: Subhorizons with up to 10 percent hard and firm durinodes are in some pedons.

Bq horizons
Value: 5 through 7 dry, 3 through 5 moist.
Chroma: 2 through 4.
Texture: Sandy loam or loam.
Structure: Subangular blocky or massive.
Rock fragments: 0 to 30 percent, mainly gravel and cobbles.
Consistence: Slightly hard or hard dry; friable or firm, moist.
Silica cementation: 20 to 80 percent durinodes or has up to 50 percent weak discontinuous cementation.
Reaction: Slightly alkaline through strongly alkaline.

2Bq or 2Ck horizons
Value: 4 or 5 moist.
Texture: Very gravelly or extremely gravelly sand.
Clay content: 2 to 8 percent.
Rock fragments: 50 to 75 percent, mainly gravel.
Consistence: Slightly hard or hard, dry; very friable through firm, moist. Layers with secondary silica are continuously brittle in some pedons.
Silica cementation: Up to 80 percent weak discontinuous cementation.
Secondary carbonates: None to many lime coats on rock fragments.
Effervescence: Noneffervescent to slightly effervescent.

COMPETING SERIES: There are no competing series.

GEOGRAPHIC SETTING: Gochea soils are on fan piedmont remnants, stream terraces, and mountain valley fans. These soils formed in alluvium derived from mixed rocks and colluvium derived from weathered tuffs, basalts, rhyolite, andesite and conglomerate with some influence from loess. Slopes are 2 to 30 percent. Elevations are 1,555 to 2,170 meters. The climate is cool and semiarid with moist winters and dry summers. The mean annual precipitation is 250 to 360 mm, average annual temperature is 6 to 8 degrees C, and the frost-free season is about 80 to 100 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Donna and Stampede soils. Donna soils have very fine textured argillic horizons and indurated duripans. Stampede soils have fine textured argillic horizons and have indurated duripans.

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

USE AND VEGETATION: Rangeland and wildlife habitat. The vegetation is principally big sagebrush, Indian ricegrass, antelope bitterbrush, bluebunch wheatgrass, Idaho fescue, cheatgrass and lupine.

DISTRIBUTION AND EXTENT: Northeastern Nevada. MLRA 25. These soils are not extensive.

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

SERIES ESTABLISHED: Elko County, Nevada, Central Part, 1986.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the surface to 30 cm (A1, A2 and Bt1 horizons).
Argillic horizon - The zone from 18 to 53 cm (Bt1 and Bt2 horizons).
Duric horizon - The zone from 53 to 150 cm (Bq and 2Bq horizons).
Aridic feature - An aridic soil moisture regime bordering on xeric.
Particle-size control section - The zone from 18 to 53 cm (Bt1 and Bt2 horizons).

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National Cooperative Soil Survey
U.S.A.