LOCATION SILVERBOW NV

Established Series
Rev. TM/WED/RLB/JBF
06/2016

SILVERBOW SERIES

The Silverbow series consists of very shallow and shallow over a indurated duripan, well drained soils formed in colluvium and alluvium derived from basalt and related rocks. Silverbow soils are on mountain footslopes, alluvial fans, fan piedmonts, ballenas, pediments and hills. Slopes are 2 to 30 percent. The mean annual precipitation is about 150 mm and the mean annual temperature is about 12 degrees C.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic, shallow Typic Argidurids

TYPICAL PEDON: Silverbow very stony very fine sandy loam--rangeland. (Colors are for dry soil unless otherwise noted.) A pavement of somewhat angular stones and cobbles ranging up to 38 cm in size are on the surface.

A--0 to 5 cm; light brownish gray (10YR 6/2) very stony very fine sandy loam, dark grayish brown (10YR 4/2) moist; weak fine granular structure and in places weak fine, or medium platy structure that parts readily to fine granular; soft, very friable, nonsticky and nonplastic; common fine roots; many fine tubular and interstitial, and few fine vesicular pores; 20 percent stones, 20 percent cobbles and 10 percent gravel; slightly effervescent; strongly alkaline (pH 8.5); clear smooth boundary. (5 to 10 cm thick)

Bt--5 to 20 cm; brown (7.5YR 5/4) very stony clay loam, brown (7.5YR 5/4) moist; moderate fine subangular blocky structure; slightly hard, friable, moderately sticky and moderately plastic; many very fine and fine roots; many fine tubular pores; common distinct clay films on faces of peds and lining pores; 20 percent stones, 20 percent cobbles and 10 percent gravel; slightly effervescent; strongly alkaline (pH 8.5); clear smooth boundary. (10 to 18 cm thick)

Btk--20 to 33 cm; brown (10YR 5/3) very stony clay loam, brown (10YR 5/3) moist; moderate medium subangular blocky structure; hard, friable, moderately sticky and moderately plastic; common very fine and fine roots; many fine tubular pores; few faint clay films on faces of peds; 20 percent stones, 20 percent cobbles, and 10 percent gravel; strongly effervescent and violently effervescent; common large faint light gray (10YR 7/2) carbonate segregations occur; strongly alkaline (pH 8.5); abrupt wavy boundary. (5 to 18 cm thick)

Bqkm1--33 to 41 cm; very pale brown (10YR 8/2) very stony silica-carbonate indurated duripan, light gray (10YR 7/2) moist; massive; extremely hard, extremely firm; few very fine roots in fractures of the duripan; upper surface is laminar; violently effervescent; strongly alkaline (pH 8.5); clear wavy boundary. (5 to 20 cm thick)

Bqkm2--41 to 91 cm; very pale brown (10YR 8/2) weakly silica-carbonate cemented colluvial stones and boulders, light gray (10YR 7/2) moist; massive; violently effervescent; strongly alkaline (pH 8.6).

TYPE LOCATION: Lincoln County, Nevada; about 1,490 feet north and 1,050 feet west of the southeast corner of Section 2, T. 3 S., R. 54 E.; USGS White Blotch Springs NE 7.5 minute topographic quadrangle; latitude 37 degrees 42 minute 45 seconds N and longitude 115 degrees 51 minutes 55 seconds W; WGS84 Decimal Degrees 37.712500 latitude, -115.8652778 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually dry, moist in some part for short periods during winter and early spring months and for 10 to 20 days cumulative between July and October due to convection storms; typic aridic soil moisture regime.
Mean annual soil temperature: 12 to 15 degrees C.
Depth to indurated pan: 20 to 36 cm.
Reaction: Moderately alkaline or strongly alkaline.
Other features: Some pedons have strongly cemented layers below the indurated duripan.

Particle-size control section - Clay content: 20 to 35 percent.
Rock fragments: 50 to 70 percent, dominantly stones or cobbles.

A horizon
Value: 5 or 6 dry, 3 or 4 moist. (Dark colors due to parent material)
Chroma: 2 or 3.
Effervescence: Noneffervescent through strongly effervescent.

Bt horizon
Hue: 7.5YR or 10YR.
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 3 or 4.
Texture: Clay loam or sandy clay loam.
Rock fragments: 50 to 70 percent, dominantly stones or cobbles.
Effervescence: Slightly effervescent through strongly effervescent.

Btk horizon
Value: 5 or 6 dry, 3 through 5 moist.
Chroma: 3 or 4.
Texture: Clay loam or sandy clay loam.
Rock fragments: 50 to 70 percent, mainly cobbles or stones.
Effervescence: Slightly effervescent to violently effervescent. Carbonates occurs as soft masses or filaments and as concretions in some pedons.

COMPETING SERIES: These are the Lyda, Maggie, Stingdorn, Tokoper and Tomel series.

Lyda soils have an E horizon and prismatic primary structure in the upper part of the argillic horizon. Maggie soils are moderately deep to bedrock. Stingdorn and Tokoper soils have bedrock within 50 cm of the surface. Tomel soils have 35 to 50 percent gravel in the particle-size control section.

GEOGRAPHIC SETTING: Silverbow soils are on mountain footslopes, alluvial fans, ballenas, hills and alluvial fan piedmonts. These soils formed in colluvium and alluvium derived from basalt and related rocks. Slopes are 2 to 30 percent. Elevations are 1,390 to 2,100 meters. The mean annual precipitation is 100 to 200 mm, the mean annual temperature is 10 to 12 degrees C, and the frost-free season is 100 to 150 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Fang and Tickapoo soils. Fang soils are very deep and are coarse-loamy. Tickapoo soils have a clayey argillic horizon.

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

USE AND VEGETATION: Rangeland and wildlife habitat. The vegetation is principally Anderson wolfberry, Nevada ephedra, littleleaf horsebrush, spiny hopsage, galleta, Indian ricegrass and spiny menodora.

DISTRIBUTION AND EXTENT: South-central Nevada. These soils are not extensive. MLRA 29.

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

SERIES ESTABLISHED: Nye County (Big Smoky Valley Area), Nevada, 1972.

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 33 cm (Bt and Btk horizons).
Indurated duripan - The zone from 33 to 41 cm (Bqkm horizon)
Particle-size control section - The zone from the soil surface to 33 cm (A, Bt, and Btk horizons).

National Cooperative Soil Survey
U.S.A.