LOCATION KEEFA                   NV

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

KEEFA SERIES

The Keefa series consists of very deep, well drained soils that formed in alluvium derived from mixed rocks. Keefa soils are on inset fans, fan skirts and lake plains. Slopes are 0 to 8 percent. Mean annual precipitation is about 150 mm and mean annual temperature is about 12 degrees C.

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, mesic Durinodic Haplocambids

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

A1--0 to 5 cm; pale brown (10YR 6/3) sandy loam, brown (10YR 4/3) moist; moderate medium platy structure; soft, very friable, nonsticky and nonplastic; few very fine roots; many very fine and fine vesicular pores; 10 percent gravel; strongly effervescent; moderately alkaline (pH 8.2); abrupt smooth boundary. (3 to 10 cm thick)

A2--5 to 13 cm; pale brown (10YR 6/3) sandy loam, brown (10YR 4/3) moist; moderate medium platy structure; slightly hard, very friable, nonsticky and nonplastic; few very fine and fine roots; many very fine and fine and common medium vesicular pores; 5 percent gravel; strongly effervescent; moderately alkaline (pH 8.2); abrupt smooth boundary. (0 to 10 cm thick)

Bw--13 to 28 cm; light yellowish brown (10YR 6/4) sandy loam, dark yellowish brown (10YR 4/4) moist; moderate medium subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; common very fine and fine roots; many very fine to medium tubular pores; 5 percent gravel; strongly effervescent; moderately alkaline (pH 8.4); abrupt smooth boundary. (13 to 38 cm thick)

Bk1--28 to 46 cm; very pale brown (10YR 7/4) sandy loam, yellowish brown (10YR 5/4) moist; massive; slightly hard, very friable, nonsticky and nonplastic; common very fine to medium roots; many very fine to medium tubular pores; 5 percent gravel; common thin carbonate pendants on rock fragments; few carbonate filaments; violently effervescent; moderately alkaline (pH 8.4); abrupt smooth boundary. (13 to 30 cm thick)

Bk2--46 to 69 cm; light yellowish brown (10YR 6/4) sandy loam, dark yellowish brown (10YR 4/4) moist; massive; soft, very friable, nonsticky and nonplastic; common very fine to medium roots; many very fine to medium tubular pores; 10 percent gravel; few thin carbonate pendants on rock fragments; strongly effervescent; strongly alkaline (pH 8.6); abrupt wavy boundary. (0 to 38 cm thick)

Bqk--69 to 91 cm; light yellowish brown (10YR 6/4) gravelly sandy loam, dark yellowish brown (10YR 4/4) moist; massive; hard, firm, brittle; common very fine and fine roots; common very fine and fine tubular pores; 15 percent gravel; continuous brittle matrix; common silica-carbonate filaments and pendants on rock fragments; violently effervescent; very strongly alkaline (pH 9.2); abrupt wavy boundary. (15 to 90 cm thick)

C--91 to 152 cm; light yellowish brown (10YR 6/4) stratified very gravelly sand to gravelly sandy loam, dark yellowish brown (10YR 4/4) moist; massive; soft, very friable, nonsticky and nonplastic; many very fine to medium roots; many very fine to coarse interstitial pores; 30 percent gravel; discontinuous lenses of weakly or strongly silica-carbonate cementation; strongly effervescent; moderately alkaline (pH 8.0).

TYPE LOCATION: Esmeralda County, Nevada; northwest of Goldpoint, Nevada; about 1,500 feet north and 1,700 feet west of the southeast corner of section 24, T. 6 S., R. 41 E.; USGS Lida 7.5 minute topographic quadrangle; latitude 37 degrees 23 minutes 58 seconds N and longitude 117 degrees 22 minutes and 52 seconds W; WGS84 Decimal Degrees 37.3994444 latitude, -117.3811111 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 duric features: 50 to 90 cm.
Effervescence: Strongly effervescent or violently effervescent in all parts. A and Bw horizons are affected by recharge of carbonates as dust.

Particle-size control section - Clay content: 8 to 15 percent.
Rock fragments: 10 to 25 percent.

A horizon
Value: 6 or 7 dry, 4 or 5 moist.
Chroma: 3 or 4.

Bw horizon
Value: 6 or 7 dry, 4 or 5 moist.
Chroma: 3 through 6.
Texture: Sandy loam or coarse sandy loam.
Rock fragments: 0 to 25 percent, one-half or more are less than 5 mm diameter.
Structure: Moderate or strong, subangular blocky.
Consistence: Very friable or friable, nonsticky or slightly sticky, nonplastic or slightly plastic
Reaction: Moderately alkaline or strongly alkaline.

Bk horizon
Value: 6 through 8 dry, 4 or 5 moist.
Chroma: 2 through 6.
Texture: Sandy loam or coarse sandy loam.
Rock fragments: 0 to 30 percent, one-half or more are less than 5 millimeter diameter.
Structure: Massive or subangular blocky.
Consistence: Soft or slightly hard, nonsticky or slightly sticky, nonplastic to slightly plastic.
Reaction: Moderately alkaline or strongly alkaline.

Bqk horizon
Value: 5 through 7 dry, 4 or 5 moist.
Chroma: 3 through 6.
Texture: Sandy loam, coarse sandy loam; subhorizons of loamy sand are in some pedons.
Rock fragments: 15 to 35 percent, one-half or more are less than 5 mm diameter.
Reaction: Strongly alkaline or very strongly alkaline.
Other features: Discontinuous lenses of weakly or strongly silica- carbonate cemented material are in some pedons.

C horizon (when present)
Value: 6 or 7 dry, 4 or 5 moist.
Chroma: 3 through 6.
Texture: Sandy loam through sand.
Rock fragments: 15 to 35 percent.
Reaction: Moderately alkaline or strongly alkaline.

COMPETING SERIES: These are the Broyles, Crockies, Gardenvalley, Strike and Weso series. Broyles, Crokies, Strike and Weso soils are not moist for 10 to 20 days in the summer. Gardenvalley soils have 20 to 40 durinodes and lack a continuous brittle matrix.

GEOGRAPHIC SETTING: Keefa soils are on inset fans fan skirts and lake plains. They formed in alluvium derived from mixed rocks. Slopes are 0 to 8 percent. Elevation is 1,345 to 1,985 meters. The mean annual precipitation is 100 to 200 mm; mean annual temperature is 11 to 14 degrees C, and the frost-free season is 120 to 160 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Belted and Itme series. Belted soils have an indurated duripan at a shallow depth. Itme soils are sandy-skeletal and lack a duric layer.

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

USE AND VEGETATION: Livestock grazing. Present vegetation is mainly shadscale, winterfat and bud sagebrush with a heavy infestation of locoweed.

DISTRIBUTION AND EXTENT: South-central Nevada. Keefa soils are inextensive. MLRA 28A, 29.

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

SERIES ESTABLISHED: Esmeralda County, Nevada, 1984.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - From the soil surface to 18 cm (A1, A2 and part of Bw horizons).
Cambic horizon - The zone from 13 to 28 cm (Bw horizon).
Duric horizon - The zone from 66 to 91 cm (Bqk horizon).
Particle-size control section - The zone from 25 to 100 cm (Bk1, Bk2, Bqk, part of Bw and C horizons).

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National Cooperative Soil Survey
U.S.A.