LOCATION SHAMOCK                 NV

Established Series
Rev. LJL/RLB/TM
12/2015

SHAMOCK SERIES

The Shamock series consists of moderately deep over a duripan, well drained soils that are on fan remnants, alluvial plains and relict alluvial flats. Shamock soils formed in mixed alluvium. Slopes are 0 to 4 percent. The mean annual precipitation is about 4 inches and the mean annual air temperature is about 66 degrees F.

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, thermic Typic Haplodurids

TYPICAL PEDON: Shamock gravelly fine sandy loam - rangeland. (Colors are for dry soil unless otherwise noted.) The soil surface is covered by approximately 40 percent pebbles overlain by a 1/4 to 1/2 inch thick mantle of windblown sand.

A1--0 to 2 inches; pale brown (10YR 6/3) gravelly fine sandy loam, yellowish brown (10YR 5/4) moist; moderate medium platy structure; soft, very friable, nonsticky and nonplastic; few very fine roots; common very fine vesicular and common very fine and fine interstitial pores; 25 percent pebbles; strongly effervescent; moderately alkaline (pH 8.2); abrupt smooth boundary. (1 to 3 inches thick)

A2--2 to 4 inches; pale brown (10YR 6/3) gravelly fine sandy loam, yellowish brown (10YR 5/4) moist; weak coarse subangular blocky structure; soft, very friable, nonsticky and nonplastic; few very fine and coarse roots; common very fine and few fine interstitial pores; 15 percent pebbles; violently effervescent; moderately alkaline (pH 8.2); clear wavy boundary. (2 to 3 inches thick)

Bk1--4 to 16 inches; very pale brown (10YR 7/3) gravelly fine sandy loam, yellowish brown (10YR 5/4) moist; weak coarse subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine, few fine and coarse roots; common very fine and few fine interstitial pores; 20 percent pebbles; few fine calcium carbonate filaments; violently effervescent; moderately alkaline (pH 8.2); clear wavy boundary. (10 to 15 inches thick)

Bk2--16 to 21 inches; very pale brown (10YR 7/4) gravelly sandy loam, yellowish brown (10YR 5/4) moist; massive; soft, very friable, nonsticky and nonplastic; common very fine, few fine and coarse roots; common very fine and few fine interstitial pores; 20 percent pebbles; few fine calcium carbonate filaments in cracks and pores; strongly effervescent matrix; moderately alkaline (pH 8.4); clear wavy boundary. (5 to 18 inches thick)

Bqk--21 to 37 inches; very pale brown (10YR 7/4) gravelly fine sandy loam, yellowish brown (10YR 5/6) moist; massive; soft, very friable, nonsticky and nonplastic; many very fine and few fine roots; common very fine and few fine interstitial pores; 20 percent pebbles, 5 percent as cobbles; 65 percent rounded and subangular weakly cemented durinodes; many distinct calcium carbonate and silica coats on undersides of rock fragments; strongly effervescent matrix, violently effervescent on some durinodes and in some pores; strongly alkaline (pH 8.6); clear wavy boundary. (0 to 16 inches thick)

2Bqkm1--37 to 58 inches; very pale brown (10YR 7/4) strongly cemented duripan with indurated lamellae, yellowish brown (10YR 5/6) moist; massive; very hard, very firm; few very fine roots in fractures; few very fine interstitial pores; 25 percent pebbles, 5 percent cobbles; violently effervescent; strongly alkaline (pH 8.6); clear wavy boundary. (18 to 28 inches thick)

2Bqkm2--58 to 60 inches; very pale brown (10YR 8/3) strongly cemented and indurated hardpan with thin (less than 1/16 inch) laminar cap, brownish yellow (10YR 6/6) moist; massive; very hard and extremely hard, very firm and extremely firm; 40 percent pebbles, 5 percent cobbles; violently effervescent.

TYPE LOCATION: Nye County, Nevada; approximately 2500 feet south and 100 feet east of the northwest corner of section 25, T. 15 S., R. 49 E.

RANGE IN CHARACTERISTICS:

Soil moisture - Usually dry; Typic Aridic moisture regime. The ratio of soil moisture utalized for evapotranspiration between summer and winter is about 0.4:1, typical of the Mojave Desert.

Soil temperature - 64 to 70 degrees F.

Other features - A thin layer (1/4 to 1/2 inch thick) of loose windblown sand commonly covers the surface.

Depth to duripan - 25 to 40 inches.

Control section - Clay content: 5 to 10 percent.

Rock fragments: Averages 15 to 35 percent, mainly gravel.

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

Chroma: 3 through 5.

Reaction: Moderately alkaline or strongly alkaline.

Effervescence: Noneffervescent to violently effervescent.

Bk1 horizon - Value: 5 through 7 dry, 4 through 6 moist.

Chroma: 2 through 4 dry, 3 or 4 moist.

Texture: Sandy loam or fine sandy loam.

Structure: Weak or moderate, medium or coarse.

Effervescence: Strongly effervescent or violently effervescent.

Reaction: Moderately alkaline or strongly alkaline.

Bk2 horizon - Value: 5 through 7 dry, 4 through 6 moist.

Chroma: 2 through 4 dry, 3 or 4 moist.

Texture: Sandy loam or fine sandy loam.

Structure: Massive or subangular blocky.

Consistence: Nonsticky or slightly sticky.

Effervescence: Strongly effervescent or violently effervescent.

Reaction: Moderately alkaline to very strongly alkaline.

Bqk horizon (when present) - Value: 6 or 7 dry.

Chroma: 4 through 6 dry.

Effervescence: Strongly effervescent or violently effervescent. Durinodes interiors commonly noneffervescent.

Reaction: Strongly alkaline or very strongly alkaline.

Cementation: 30 to 90 percent durinodes by volume .

2Bqkm horizons - Value: 7 or 8 dry; 5 or 6 moist.

Chroma: 2 through 4 dry, 4 through 6 moist.

Structure: Massive or platy.Rock fragments: 20 to 60 percent, mainly pebbles.

Effervescence: Strongly effervescent or violently effervescent.

Reaction: Strongly alkaline or very strongly alkaline.

Cementation: Indurated or very strongly cemented, may include strongly cemented material in some parts.

COMPETING SERIES: There are no competing series.

GEOGRAPHIC SETTING: Shamock soils are on fan remnants, alluvial plains and relict alluvial flats. These soils formed in mixed alluvium. Slopes are 0 to 4 percent. Elevations are 2,400 to 3,800 feet. The climate is arid with cool winters and summers are hot and dry, typical of the Mojave Desert. The mean annual precipitation is 3 to 7 inches; average annual air temperature is 61 to 70 degrees F. The frost-free season is 200 to 300 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Arizo, Corbilt and Canutio series. Corbilt soils have a hardpan below the control section, but within a depth of 60 inches. Arizo and Canutio soils are skeletal and lack a hardpan within a depth of 60 inches.

DRAINAGE AND PERMEABILITY: Well drained; high runoff; moderately rapid permeability.

USE AND VEGETATION: Rangeland and wildlife habitat. The vegetation is mainly creosotebush with some chorizanthe, Indian ricegrass and white bursage.

DISTRIBUTION AND EXTENT: Mojave Desert of southern Nevada; MLRA 30., Shamock soils are moderately extensive.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: PHOENIX, ARIZONA

SERIES ESTABLISHED: Nye County, Nevada, (Southwest Part) 1994. The name is coined.

REMARKS: Diagnostic horizons and features recognized in this pedon are:

Ochric epipedon 0 to 7 inches (A1, A2 and part of the Bk1 horizons).

Duripan - 37 to 60 inches (2Bqkm1 and 2Bqkm2 horizons)

Particle-size control section: 10 to 37 inches (Part of the Bk1, Bk2 and Bqk horizons).

Responsibility for this series was transferred from Davis to Phoenix 12/2015. The last revision to the series was 3/2006. ET

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National Cooperative Soil Survey
U.S.A.