LOCATION SPIKE                   NV

Established Series
Rev. CEJ-RLB-JVC-JBF
11/2016

SPIKE SERIES

The Spike series consists of very deep, well drained soils that formed in alluvium derived from mixed rocks. Spike soils are on fan remnants. Slopes are 30 to 50 percent. The mean annual precipitation is about 230 mm and the mean annual temperature is about 9 degrees C.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic Xeric Paleargids

TYPICAL PEDON: Spike very gravelly sandy loam--rangeland. (Colors are for dry soil unless otherwise noted). The surface is partially covered by approximately 70 percent gravel and 5 percent cobbles.

A1--0 to 3 cm; very pale brown (10YR 7/3) very gravelly sandy loam, brown (10YR 4/3) moist; moderate medium platy structure; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots; many fine vesicular pores; 35 percent gravel; moderately alkaline (pH 8.4); abrupt smooth boundary. (3 to 15 cm thick)

A2--3 to 5 cm; pale brown (10YR 6/3) gravelly loam, dark yellowish brown (10YR 4/4) moist; weak thin platy structure; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots; many fine vesicular and tubular pores; 25 percent gravel; moderately alkaline (pH 8.4); abrupt smooth boundary. (0 to 3 cm thick)

2Btn--5 to 15 cm; yellowish brown (10YR 5/6) very gravelly clay, dark yellowish brown (10YR 4/6) moist; strong fine angular blocky structure; very hard, firm, very sticky and very plastic; common very fine and fine roots; common very fine and fine tubular pores; many distinct clay films on faces of peds and lining pores; 45 percent gravel; moderately alkaline (pH 8.4); clear wavy boundary. (3 to 15 cm thick)

2Btkn1--15 to 36 cm; light yellowish brown (10YR 6/4) very gravelly clay loam, yellowish brown (10YR 5/4) moist; weak fine subangular blocky structure; very hard, friable, very sticky and moderately plastic; few fine roots; common very fine and fine tubular and interstitial pores; common distinct clay films on faces of peds and lining pores; 45 percent gravel and 10 percent cobbles; secondary carbonates segregated as common medium masses and common coats on the bottoms of rock fragments; strongly effervescent; strongly alkaline (pH 8.8); clear wavy boundary. (5 to 20 cm thick)

2Btkn2--36 to 46 cm; light yellowish brown (10YR 6/4) extremely gravelly sandy clay loam, dark yellowish brown (10YR 4/6) moist; massive, very hard, firm, moderately sticky and moderately plastic; few very fine roots; common very fine and fine tubular pores; common faint clay bridges between mineral grains; 60 percent gravel and 5 percent cobbles; secondary carbonates segregated as common coats on bottoms of rock fragments; strongly effervescent; strongly alkaline (pH 8.6); gradual wavy boundary. (0 to 13 cm thick)

2Btkn3--46 to 76 cm; very pale brown (10YR 7/4) extremely gravelly sandy clay loam, brownish yellow (10YR 6/6) moist; massive; hard, friable, moderately sticky and moderately plastic; very few fine roots; common very fine and fine interstitial pores; common faint clay bridges between mineral grains; 55 percent gravel and 10 percent cobbles; secondary carbonates segregated as common medium masses and common coats on bottoms of rock fragments; strongly effervescent; moderately alkaline (pH 8.4); gradual wavy boundary. (0 to 30 cm thick)

3Btky1--76 to 112 cm; very pale brown (10YR 7/4) extremely gravelly clay loam, brownish yellow (10YR 6/6) moist; massive; hard, friable, moderately sticky and moderately plastic; very few fine roots; common very fine and fine interstitial pores; common faint clay bridges between mineral grains; 55 percent gravel and 10 percent cobbles; secondary carbonates segregated as common medium masses and common coats on bottoms of rock fragments; common medium filaments of gypsum; violently effervescent; moderately alkaline (pH 8.2); gradual wavy boundary. (25 to 40 cm thick)

3Btky2--112 to 152 cm; very pale brown (10YR 7/3) extremely gravelly sandy clay loam, light yellowish brown (10YR 6/4) moist; massive; hard, friable, moderately sticky and moderately plastic; few fine tubular pores; common faint clay bridges between mineral grains; 50 percent gravel and 10 percent cobbles; secondary carbonates segregated as common medium masses and common coats on bottoms of rock fragments; common medium filaments of gypsum; violently effervescent; strongly alkaline (pH 8.6).

TYPE LOCATION: Lander County, Nevada; about 22 miles north of Austin; approximately 600 feet south and 2,950 feet east of the northwest corner of section 24, T. 23 N., R. 43 E.; USGS Joe Eason Mountain 7.5 minute topographic quadrangle; latitude 39 degrees 51 minutes 10 seconds N and longitude 117 degrees 5 minutes 20 seconds W; WGS84 Decimal Degrees 39.8527778 latitude, -117.0888889 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist in winter and early spring, dry mid-May to October; aridic soil moisture regime that borders on xeric.
Mean annual soil temperature: 8 to 12 degrees C.
Depth to base of argillic horizon: 100 to more than 150 cm.
Reaction: Moderately alkaline through strongly alkaline.
Depth to horizons with secondary carbonates: 13 to 30 cm.
Depth to horizons with secondary gypsum: 30 to 90 cm.

Particle-size control section - Clay content: Average 27 to 35 percent.
Rock fragments: 35 to 60 percent, mainly gravel. Lithology of fragments is mixed rocks.

A horizons
Value: 6 or 7 dry, 4 or 5 moist.
Chroma: 2 through 4, dry or moist.
Clay content: 12 to 20 percent.

Btn horizon
Value: 5 through 7 dry, 4 through 6 moist.
Chroma: 3 through 6, dry or moist.
Texture: Very gravelly clay, very gravelly clay loam, or very gravelly sandy clay.
Clay content: 35 to 45 percent.
Rock fragments: 35 to 60 percent.
Structure: Angular blocky, subangular blocky or is massive in the lower subhorizons.
Sodicity (SAR): 13 to 45.

Btkn and Btky horizons
Texture: Clay loam, sandy clay loam, or loam.
Modifiers: Extremely gravelly or very gravelly.
Clay content: 20 to 30 percent.
Rock fragments: 50 to 75 percent.
Sodicity (SAR): 13 to 45.
Calcium carbonate equivalent: 1 to 5 percent.
Gypsum content: 1 to 5 percent.
Other features: Some pedons have horizons with texture of extremely gravelly sandy loam or extremely gravelly loam below 100 cm.

COMPETING SERIES: There are currently no other series in this family.

GEOGRAPHIC SETTING: Spike soils are on fan remnants. They typically occur on south-facing backslope positions. These soils formed in alluvium derived from mixed rocks. Slopes are 30 to 50 percent. Elevations range from 1,650 to 1,895 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 11 degrees C, and the frost-free period is 100 to 130 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Buffaran, Desatoya, Grassval and Pula soils. Buffaran and Grassval soils are less than 50 cm deep to an indurated duripan. Desatoya soils have less than 35 percent gravel in the upper part of the Bt horizon. Pula soils have thicker surface horizons and have sodium adsorption ratio of less than 13 in the Bt horizon.

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

USE AND VEGETATION: Spike soils are used for livestock grazing and wildlife habitat. The present vegetation is mainly Wyoming big sagebrush with sparse shadscale, bud sagebrush, small rabbitbrush, Indian ricegrass, bottlebrush squirreltail, ephedra, and galleta.

DISTRIBUTION AND EXTENT: Central Nevada. These soils are not extensive with about 5,300 acres of the series mapped to date. MLRA 28B.

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

SERIES ESTABLISHED: Lander County (South Part), Nevada, 1985.

REMARKS: The revision of September 2003 updates the taxonomic class from Loamy-skeletal, mixed, superactive, mesic Typic Haplargids.

Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 5 cm (A1 and A2 horizons).
Argillic horizon - The zone from 5 to 152 cm (2Btn, 2Btkn1, 2Btkn2, 2Btkn3, 3Btky1, and Btky2 horizons).
Paleargid great group feature - The abrupt increase in clay content of more than 15 percent at 5 cm (between the A2 and 2Btn horizons).
Identifiable secondary carbonates - The zone from 15 to 152 cm (2Btkn1, 2Btkn2, 2Btkn3, 3Btky1, and Btky2 horizons).
Particle-size control section - The zone from 5 to 55 cm (Btn, Btkn1, and Btkn2 horizons and part of the Btkn3 horizon).

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National Cooperative Soil Survey
U.S.A.