LOCATION ARADA                   NV+AZ

Established Series
Rev. LNL/DJM/RLB
04/2015

ARADA SERIES

The Arada series consists of very deep, somewhat excessively drained soils that formed in sandy aeolian material over mixed alluvium. The Arada soils are on fan piedmonts, sand sheets, terraces and alluvial fans. Slopes are 0 to 8 percent. The mean annual precipitation is about 5 inches and the mean annual temperature is about 64 degrees F.

TAXONOMIC CLASS: Sandy, mixed, thermic Typic Haplocalcids

TYPICAL PEDON: Arada fine sand, rangeland. (Colors are for dry soil unless otherwise noted.)

A--0 to 6 inches; pink (5YR 7/4) fine sand, yellowish red (5YR 5/6) moist; single grain; loose; common very fine roots; many very fine interstitial pores; violently effervescent; moderately alkaline (pH 8.2); clear smooth boundary. (5 to 15 inches thick)

C1--6 to 16 inches; pink (5YR 7/4) fine sand, yellowish red (5YR 5/6) moist; single grain; loose; common very fine roots; many very fine interstitial pores; violently effervescent; strongly alkaline (pH 8.8); clear smooth boundary. (8 to 20 inches thick)

C2--16 to 27 inches; pink (7.5YR 7/4) fine sand, brown (7.5YR 5/4) moist; single grain; loose; few very fine and fine roots; many very fine interstitial pores; violently effervescent; strongly alkaline (pH 8.8); clear smooth boundary. (6 to 14 inches thick)

2Bk1--27 to 37 inches; pink (7.5YR 7/4) gravelly loamy fine sand, brown (7.5YR 7/4) moist; massive; soft, very friable, nonsticky and nonplastic; few very fine roots; few very fine tubular, and many very fine interstitial pores; common medium soft lime masses; common thin lime coats and pendants coating rock fragments; 25 percent pebbles; violently effervescent; strongly alkaline (pH 8.8); abrupt wavy boundary. (4 to 14 inches thick)

2Bk2--37 to 43 inches; pinkish white (7.5YR 8/2) extremely gravelly sandy loam, light brown (7.5YR 6/4) moist; massive; hard, firm, nonsticky and nonplastic; few very fine roots; few very fine tubular, and many very fine interstitial pores; weakly lime cemented platelike masses throughout; many moderately thick lime coats completely coating rock fragments; 65 percent pebbles; violently effervescent; strongly alkaline (pH 8.8); abrupt wavy boundary. (5 to 36 inches thick)

2Bk3--43 to 60 inches; very pale brown (10YR 8/3) extremely gravelly loamy coarse sand, very pale brown (10YR 7/3) moist; massive; hard, friable, nonsticky and nonplastic; few very fine roots; many very fine and fine interstitial pores; weakly lime cemented matrix with many moderately thick lime coats completely coating rock fragments; 80 percent pebbles; 5 percent cobbles; violently effervescent; strongly alkaline (pH 9.0).

TYPE LOCATION: Clark County, Nevada; adjacent to Stringtown Road in Moapa Valley; approximately 1,000 feet south and 350 feet east of the northwest corner of section 26, T.15 S., R.67 E.

RANGE IN CHARACTERISTICS:

Soil moisture - Usually dry, most in some part for short periods during winter and early spring and for 10 to 20 days cumulative between July and October following summer convection storms.

Soil temperature - 63 to 68 degrees F.

Depth to 2Bk horizons - 24 to 39 inches.

Control section - Clay content: 0 to 10 percent.

Rock fragments - Averages 5 to 15 percent.

A horizon - Hue: 5YR or 7.5YR

Value: 6 or 7 dry, 4 or 5 moist.

Chroma: 4 through 6.



C horizons - Hue: 5YR or 7.5YR

Chroma: 4 through 6

Value: 6 or 7 dry, 4 through 6 moist

Texture of the fine earth: Typically averages fine sand, but includes loamy sand and strata of loamy fine sand.

Structure: Single grain or is massive

Consistence: Loose or soft

Effervescence: Strongly effervescent or violently effervescent



2Bk1 horizon - Hue: 7.5YR or 10YR

Chroma: 2 through 6.

Value: 6 through 8 dry, 5 through 7 moist.

Texture of the fine earth: Sandy loam, coarse sandy loam, or loamy fine sand.

Rock fragments: 15 to 35 percent pebbles.

Structure: Weak subangular blocky or massive

Consistence: Soft or slightly hard.

Calcium carbonate equivalent: 20 to 40 percent by weight.

Other features: Some pedons have few to many thin lime coats on vertical and undersides of rock fragments.



2Bk2 and 2Bk3 horizons - Hue: 10YR or 7.5YR

Chroma: 1 through 4.

Value: 6 through 8 dry, 5 through 7 moist.

Texture: Stratified extremely gravelly fine sandy loam, extremely gravelly sandy loam or extremely gravelly coarse sandy loam.

Rock fragments: 60 to 85 percent, dominantly pebbles

Consistence: Hard through extremely hard

Calcium carbonate equivalent: 20 to 40 percent by weight

Other features: Some pedons are weakly to strongly lime cemented below depths of 30 to 58 inches.

COMPETING SERIES: These are the Knobhill (NV), Lovelace (CA) and Rilloso (T NM) series. Knobhill soils have greater than 15 percent rock fragments in the upper part of the control section and have a depth to the calcic horizon of 16 to 24 inches. Lovelace soils have a depth to the calcic horizon of 16 to 24 inches and lack appreciable summer precipitation. Rilloso soils have a calcic horizon shallower than 16 inches.

GEOGRAPHIC SETTING: Arada soils are on fan piedmonts, sand sheets, terraces and alluvial fans. These soils formed in sandy eolian material over alluvium from mixed rock sources. Slopes are 0 to 10 percent. The elevations are 1400 to 3000 feet. The climate semiarid with cool, moist winters and hot, dry summers. The mean annual precipitation is 5 to 8 inches; the mean annual temperature is 57 to 70 degrees F., and the frost free season is about 180 to 270 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Tonopah, Toquop, Bard, Land, and Mormon Mesa soils. Bard and Mormon Mesa soils have petrocalcic horizons at depths of less than 20 inches. Land soils have fine-silty control sections and have salic horizons. Tonopah soils have sandy-skeletal control sections. Toquop soils lack a calcic horizon.

DRAINAGE AND PERMEABILITY: Somewhat excessively drained; slow runoff; moderate permeability.

USE AND VEGETATION: Range and wildlife habitat. The present vegetation is mainly Indian ricegrass, big galleta, white bursage, range ratany, creosotebush.

DISTRIBUTION AND EXTENT: Southern Nevada. These soils are moderately extensive. MLRA 30.

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

SERIES ESTABLISHED: Clark County, Nevada (Virgin River Area), 1970.

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

Ochric epipedon - The zone from about 0 to 6 inches (A horizon).

Particle-size control section - The zone from about 10 to 40 inches (C1, C2, 2Bk1 and 2Bk2 horizons).

Calcic horizon - The zone beginning about 27 inches (2Bk1, 2Bk2 and 2Bk3 horizons).

Responsibility for this series was transferred from Davis to Phoenix 4/2015. The last revision to the series was 5/1997. ET

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National Cooperative Soil Survey
U.S.A.