LOCATION YUKO                    NV

Established Series
Rev. LIL-PWB-JVC-JBF
12/2019

YUKO SERIES

The Yuko series consist of very shallow and shallow, well drained soils that formed in residuum and colluvium derived from andesite, tuff, and tuffaceous sedimentary rocks. Yuko soils are on hills and rock pediments. Slopes are 2 to 50 percent. The mean annual precipitation is about 250 mm and the mean annual temperature is about 8 degrees C.

TAXONOMIC CLASS: Loamy, mixed, superactive, mesic, shallow Xeric Haplargids

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

A--0 to 5 cm; brown (10YR 5/3) loam, dark brown (10YR 3/3) moist; massive; soft, very friable, slightly sticky and nonplastic; many very fine and fine vesicular pores; 10 percent gravel, 2 percent cobbles, and 2 percent stones; neutral (pH 6.8); abrupt wavy boundary. (5 to 15 cm thick)

Bt--5 to 20 cm; yellowish brown (10YR 5/6) silty clay loam, dark yellowish brown (10YR 4/4) moist; strong very fine subangular blocky structure; hard, friable, moderately sticky and moderately plastic; common very fine, fine and medium roots; few fine tubular pores; many distinct clay films on faces of peds and lining pores; 10 percent cobbles; neutral (pH 6.8); abrupt irregular boundary. (8 to 20 cm thick)

2Crt--20 cm; strong brown (7.5YR 5/6) highly weathered, fractured andesite; few very fine roots and clay films lining fractures.

TYPE LOCATION: Washoe County, Nevada; about 4.5 miles north of Reno between Panther Valley and Sun Valley; about 500 feet east and 1,000 feet north of the southwest corner of section 13, T. 20 N., R. 19 E.; USGS Reno 7.5 minute topographic quadrangle; latitude 39 degrees 35 minutes 43 seconds N and longitude 119 degrees 48 minutes 21 seconds W; latitude 39.5952778, longitude -119.8058333, WGS 84.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist in winter and spring, dry from June through October; aridic moisture regime that borders on xeric.
Mean annual soil temperature: 8 to 11 degrees C.
Ochric epipedon thickness: 5 to 15 cm.
Depth to bedrock: 15 to 36 cm to a paralithic contact. The paralithic materials below the contact are weathered volcanic rocks such as andesite or tuffaceous sedimentary rocks.

Particle-size control section - Clay content: Averages 27 to 35 percent.
Sand content: less than 45 percent.
Silt content: 40 to 75 percent.
Rock fragments: Averages 5 to 15 percent, mainly gravel and cobbles. Lithology of fragments are volcanic rocks such as andesite or tuff.

A horizon
Value: 4 through 6 dry, 3 or 4 moist.
Chroma: 2 or 3, dry or moist.
Clay content: 5 to 27 percent.
Reaction: Slightly acid or neutral.

Bt horizon
Hue: 7.5YR or 10YR.
Value: 4 through 6 dry, 3 or 4 moist.
Chroma: 3 through 6 dry, 2 through 6 moist.
Texture: Silt loam, silty clay loam, clay loam, or clay.
Clay content: 30 to 45 percent.
Rock fragments: 0 to 15 percent.
Reaction: Slightly acid through moderately alkaline.
Other features: Some pedons have Bt2 horizons with clay texture 2 to 10 cm thick.

COMPETING SERIES: These are the Anowell, Chill, Corral, Genaw, and Ulida series.

Anowell soils have subhorizons with 15 to 35 percent rock fragments in the particle-size control section, are calcareous throughout, and have identifiable secondary carbonates in the argillic horizon. Chill soils have 18 to 27 percent clay and 45 to 65 percent sand in the particle-size control section and have paralithic materials of weathered granite. Corral soils have less than 40 percent silt and average 18 to 27 percent clay in the particle-size control section. Genaw soils have paralithic contacts between 36 and 50 cm. Ulida soils have mean annual soil temperature of 13 to 15 degrees C. and have paralithic materials of weathered granitic rocks.

GEOGRAPHIC SETTING: Yuko soils are on hills and rock pediments. These soils formed in residuum and colluvium derived from andesite, tuff, and tuffaceous sedimentary rocks. Slopes are 4 to 50 percent. Elevations range from 1,375 to 2,135 meters. The climate is semiarid with cool, moist winters and warm, dry summers. The mean annual precipitation is 200 to 300 mm, mean annual temperature is 7 to 10 degrees C, and the frost-free period is 100 to 120 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Manogue, Oppio, Risley, Surgem, and Wedekind soils. Manogue soils have clay texture and are 100 to 150 cm deep. Oppio, Risley, and Surgem soils have clay Bt horizons and are 50 to 75 cm deep to bedrock. Risley soils are calcareous. Wedekind soils have Mollic epipedons.

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

USE AND VEGETATION: Yuko soils are used for rangeland and wildlife habitat. The present vegetation on this soil in MLRA 26 is mainly Wyoming big sagebrush, desert peach, purple sage, low rabbitbrush, green ephedra, and desert needlegrass. This pedon is associated with Ecological Site ID R026XY011NV, South Slope 8-12" P. Z.

DISTRIBUTION AND EXTENT: Western and northern Nevada. These soils are moderately extensive. The original series concept occurs in MLRA 26, while the main acreage occurs in MLRA 25.

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

SERIES ESTABLISHED: Washoe County (South Part), Nevada, 1980.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 5 cm (A horizon).
Argillic horizon - The zone from 5 to 20 cm (Bt horizon).
Paralithic contact - The boundary at 20 cm to underlying, soft weathered bedrock (2Crt layer).
Particle size control section - The zone from the soil surface to 20 cm (A and Bt horizons).

ADDITIONAL DATA: User Pedon ID: 2006NV031147.

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National Cooperative Soil Survey
U.S.A.