LOCATION ALLKER                  NV

Established Series
Rev. RAF-RLB-JVC-JBF
02/2018

ALLKER SERIES

The Allker series consists of very deep, well drained soils that formed in alluvium derived from mixed rocks with a component of loess. Allker soils are on fan remnants. Slopes are 2 to 8 percent. The mean annual precipitation is about 225 mm and the mean annual temperature is about 9 degrees C.

TAXONOMIC CLASS: Fine-loamy over sandy or sandy-skeletal, mixed, superactive, mesic Durinodic Xeric Haplargids

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

A1--0 to 8 cm; pale brown (10YR 6/3) gravelly sandy loam, brown (10YR 5/3) moist; moderate medium platy structure; slightly hard, very friable, nonsticky and nonplastic; many coarse and medium vesicular pores; 15 percent gravel; moderately alkaline (pH 8.2); abrupt smooth boundary. (5 to 10 cm thick)

A2--8 to 18 cm; pale brown (10YR 6/3) gravelly sandy loam, yellowish brown (10YR 5/4) moist; weak thin platy structure; slightly hard, very friable, nonsticky and nonplastic; common fine and very fine roots; common medium and fine tubular and vesicular pores; 15 percent gravel; moderately alkaline (pH 8.2); clear smooth boundary. (8 to 13 cm thick)

Bt1--18 to 41 cm; light yellowish brown (10YR 6/4) gravelly loam, yellowish brown (10YR 5/4) moist; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common fine and very fine roots; common fine and very fine tubular pores; 15 percent hard, firm, brittle durinodes; common distinct clay films on faces of peds and lining pores; 15 percent gravel; slightly effervescent; moderately alkaline (pH 8.4); clear smooth boundary. (13 to 28 cm thick)

Bt2--41 to 66 cm; brownish yellow (10YR 6/6) gravelly loam, yellowish brown (10YR 5/4) moist; moderate medium and fine angular blocky structure; hard, firm, moderately sticky and moderately plastic; common medium and fine roots; common fine and very fine tubular pores; many distinct clay films on faces of peds and lining pores; 15 percent gravel; slightly effervescent; moderately alkaline (pH 8.4); clear smooth boundary. (23 to 36 cm thick)

Bqk--66 to 94 cm; light yellowish brown (10YR 6/4) gravelly loam, yellowish brown (10YR 5/4) moist; moderate medium and fine angular blocky structure; hard, friable, slightly sticky and slightly plastic; common medium and fine exped roots; common fine and very fine tubular pores; thin discontinuous weakly cemented silica laminae; many moderately thick silica coats lining pores and on faces of ped; 20 percent gravel; strongly effervescent; moderately alkaline (pH 8.4); abrupt smooth boundary. (20 to 28 cm thick)

2Bqk--94 to 152 cm; yellowish brown (10YR 5/6) very gravelly loamy sand, dark yellowish brown (10YR 4/6) moist; single grain; loose, nonsticky and nonplastic; few fine roots; common fine and very fine interstitial pores; few thin discontinuous silica laminae; 55 percent gravel; strongly effervescent; strongly alkaline (pH 8.5)

TYPE LOCATION: Eureka County, Nevada; about 22 miles southeast of Crescent Valley; approximately 1,500 feet west and 2,200 feet north of the southeast corner of section 28, T. 26 N., R. 49 E.; USGS Rocky Hills 7.5 minute topographic quadrangle; latitude 40 degrees 6 minutes 21 seconds N and longitude 116 degrees 27 minutes 4 seconds W; WGS84 Decimal Degrees 40.1058333 latitude, -116.4511111 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Moist in winter and spring, dry June through October; aridic soil moisture regime bordering on xeric.
Mean annual soil temperature: 8 to 11 degrees C.
Depth to discontinuous weak silica cementation: 56 to 89 cm.
Depth to secondary carbonates: 40 to 60 cm.
Depth to sandy-skeletal material: 60 to 97 cm.
Other features: Nonsaline or slightly saline below a depth of 56 cm.

A horizons
Value: 5 or 6 dry, 3 through 5 moist (greater than 5.5 dry and 3.5 moist when the surface 18 cm are mixed).
Chroma: 2 or 3.
Reaction: Neutral to moderately alkaline.

Bt horizons
Value: 5 or 6 dry, 4 or 5 moist.
Chroma: 2 through 4.
Texture: Dominantly gravelly loam or gravelly clay loam, but ranges from gravelly loam to gravelly sandy clay loam.
Clay content: 20 to 30 percent.
Rock fragments: 15 to 30 percent, mainly gravel.
Consistence: Slightly hard or hard dry, friable or firm moist, slightly sticky or moderately sticky and slightly plastic or moderately plastic wet.
Structure: Weak to strong fine to coarse subangular or angular blocky.
Reaction: Slightly alkaline or moderately alkaline.
Other features: Carbonate segregations are common to lower subhorizons of some pedons; most pedons commonly have durinodes in some subhorizon.

Bqk horizon
Value: 6 through 8 dry, 4 through 6 moist.
Chroma: 1 through 4.
Rock fragments: 15 to 30 percent, mainly gravel.
Consistence: Hard or very hard dry, friable or firm moist.
Reaction: Moderately alkaline or strongly alkaline.
Other features: Few thin or very thin discontinuous silica laminae are common in some pedons; some pedons have durinodes in a friable matrix below the weakly cemented horizon.

2Bqk horizon
Value: 5 or 6 dry.
Chroma: 3 through 6.
Texture: Very gravelly loamy sand or very gravelly sand.
Rock fragments: 35 to 60 percent, mainly gravel.
Reaction: Moderately alkaline or strongly alkaline.
Other features: Commonly contains thin discontinuous silica laminae or durinodes in a loose or friable matrix.

COMPETING SERIES: This is the Gorzell series. Gorzell soils are 25 to 46 cm to the base of the argillic horizon and underlying horizons with secondary silica.

GEOGRAPHIC SETTING: Allker soils are on fan remnants. These soils formed in alluvium derived from mixed rocks with a component of loess. Slopes are 2 to 8 percent. Elevations range from 1,680 to 2,260 meters. The climate is semiarid with cool, moist winters and warm, dry summers. The mean annual precipitation is 200 to 250 mm, the mean annual temperature is 7 to 10 degrees C, and the frost-free period is 90 to 120 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Tenabo and Whirlo soils. Tenabo soils have a shallow indurated duripan. Whirlo soils have a cambic horizon and are loamy-skeletal.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; moderately high saturated hydraulic conductivity.

USE AND VEGETATION: Allker soils are used for livestock grazing and wildlife habitat. The present vegetation is mainly Wyoming big sagebrush, downy rabbitbrush, Sandberg's bluegrass, bottlebrush squirreltail, and Thurber's needlegrass.

DISTRIBUTION AND EXTENT: North-central Nevada. These soils are not extensive. MLRA 24, 25.

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

SERIES ESTABLISHED: Eureka County, Nevada, 1983.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from soil surface to 18 cm (A1 and A2 horizons).
Argillic horizon - The zone from 18 to 66 cm (Bt1 and Bt2 horizons).
Duric feature - The zone from 66 to 94 cm (Bqk horizon).
Identifiable secondary carbonates - The zone from 66 to 152 cm (Bqk and 2Bqk horizons).
Major lithologic discontinuity - The abrupt change to sandy-skeletal material at 94 cm (2Bqk horizon).
Particle-size control section - The zone from 18 to 100 cm (Bt1, Bt2, and Bqk horizons and part of the 2Bqk horizon).

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National Cooperative Soil Survey
U.S.A.