LOCATION RISLEY                  NV

Established Series
Rev. OWB/WED/RLB
06/2017

RISLEY SERIES


The Risley series consists of moderately deep, well drained soils that formed in residuum and colluvium derived from altered andesite, shale and sandstone. Risley soils are hillsides, mountains and rock pediments. Slopes are 2 to 50 percent. Mean annual precipitation is about 280 mm and mean annual temperature is about 9 degrees C.

TAXONOMIC CLASS: Fine, smectitic, mesic Xeric Haplargids

TYPICAL PEDON: Risley cobbly loam, rangeland. (Colors are for dry soil unless otherwise noted.) About 10 percent gravel and 10 percent cobbles cover the soil surface area.

A1--0 to 5 cm; brown (10YR 5/3) cobbly loam, dark yellowish brown (10YR 3/4) moist; weak fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine and fine roots; many very fine and fine tubular pores; 10 percent gravel and 10 percent cobbles; neutral (pH 7.2); abrupt smooth boundary. (3 to 8 cm thick)

A2--5 to 15 cm; brown (10YR 5/3) cobbly clay loam, dark yellowish brown (10YR 3/4) moist, moderate medium subangular blocky structure; slightly hard, very friable; slightly sticky and slightly plastic; many very fine and fine, and common medium roots; many very fine and fine tubular pores; 10 percent gravel and 10 percent cobbles; neutral (pH 7.2); abrupt smooth boundary. (5 to 18 cm thick)

Bt--15 to 46 cm; yellowish brown (10YR 5/4) clay, brown (7.5YR 4/4) moist; strong medium prismatic structure parting to strong medium angular blocky; very hard, friable, moderately sticky and moderately plastic; few very fine roots; few very fine and fine tubular pores; many distinct clay films on faces of peds and in the pores; slightly alkaline (pH 7.6); clear smooth boundary. (25 to 36 cm thick)

Bk--46 to 71 cm; brownish yellow (10YR 6/6) clay loam, dark yellowish brown (10YR 4/6) moist; massive; very hard, friable, moderately sticky and moderately plastic; few fine roots; few very fine and fine tubular pores; strongly effervescent; moderately alkaline (pH 8.2); gradual smooth boundary. (15 to 38 cm thick)

Cr--71 to 102 cm; highly weathered, altered andesite with carbonate seams and clay films in fractures.

TYPE LOCATION: Washoe County, Nevada; about 1,900 feet east and 900 feet south from the northwest corner of section 14, T. 24 N., R. l8 E.; USGS Seven Lakes Mountain 7.5 minute topographic quadrangle; latitude 39 degrees 57 minutes 0 seconds N and longitude 119 degrees 56 minutes 1 seconds W; WGS84 Decimal Degrees 39.9500000 latitude, -119.9336111 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually dry, moist in winter and spring, dry summer and fall; aridic soil moisture regime bordering on xeric.
Mean annual soil temperature: 9 to 10 degrees C.
Depth to soft bedrock: Usually 50 to 76 cm, some pedons have bedrock as deep as 100 cm.
Depth to Bk horizon (when present): 36 to 50 cm.
Depth to Btk horizon (when present): 20 to 50 cm.

Particle-size control section - Clay content: 35 to 55 percent.
Rock fragments: 0 to 10 percent.

A horizon
Value: 5 through 7 dry, 3 or 4 moist.
Chroma: 2 through 4.
Reaction: Medium acid through moderately alkaline.

Bt horizon
Hue: 10YR or 7.5YR.
Value: 5 or 6 dry, 3 through 5 moist.
Chroma: 2 through 4.
Texture: Clay, sandy clay or clay loam.
Clay content: 35 to 55 percent.
Reaction: Slightly acid through moderately alkaline.

Btk horizon (when present)
Hue: 10YR or 7.5YR.
Value: 4 or 5 moist.
Chroma: 4 through 6 moist.
Texture: Clay or clay loam.
Structure: Angular blocky or prismatic.
Carbonates: Strongly effervescent or violently effervescent.

Bk horizon (when present)
Reaction: Slightly alkaline or moderately alkaline.
Carbonates: Strongly effervescent or violently effervescent.

COMPETING SERIES: These are the Buncelvoir, Diaz, Farmell, Glasgow, Lanktree, Milkiway, Oppio, Schamp and Trunk series.

Buncelvoir, Farmell, Lanktree, Milkiway and Schamp soils do not have bedrock within a depth of 100 cm. Diaz, Glasgow, Oppio and Trunk soils have a lithic contact at a depth of 50 to 100 cm.

GEOGRAPHIC SETTING: Risley soils are on hillsides, mountains and rock pediments. These soils formed in residuum and colluvium derived from altered andesite and other basic volcanic rock or shale, and sandstone. Slopes are 2 to 50 percent. Elevations are 1,070 to 2,080 meters. The climate is semiarid. The mean annual precipitation is 230 to 300 mm; the mean annual temperature is 8 to 9 degrees C; and the frost-free season is 100 to l20 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Manogue, Wedekind, Yuko, Zephan, and Xman soils. Manogue soils are 100 to 150 cm deep. Wedekind soils are noncalcareous, 25 to 50 mm deep, and have less than 35 percent clay in the particle-size control section. Yuko soils are noncalcareous, 15 to 25 cm deep and have less than 35 percent clay in their particle-size control section. Xman soils are 25 to 50 cm deep to a paralithic contact. Zephan soils are noncalcareous and have more than 35 percent rock fragments in their particle-size control section.

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

USE AND VEGETATION: Risley soils are used principally for range, recreation and wildlife habitat. Native vegetation is big sagebrush, bottlebrush squirreltail, and some scattered Juniper.

DISTRIBUTION AND EXTENT: Northwestern Nevada. The series is moderately extensive. MLRA 26.

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 surface to about 15 cm. (A1 and A2 horizons).
Argillic horizon - The zone from about 15 to 46 cm. (Bt horizon).
Xeric Intergrades - Meets organic carbon requirement for xeric.
Paralithic contact - The boundary at 71 cm (Cr layer).
Particle-size control section - The zone from about 15 to 46 cm (Bt horizon).

ADDITIONAL DATA: User Pedon ID: 2006NV031102.


National Cooperative Soil Survey
U.S.A.