LOCATION HIDDENSUN               NV

Established Series
Rev. TM/LJL/RLB
04/2015

HIDDENSUN SERIES

The Hiddensun series consists of shallow, well drained soils that formed in residuum from volcanic rocks influenced by calcareous loess. Hiddensun soils are on mountains. Slope ranges from 8 to 50 percent. The mean annual precipitation is about 6 inches and the mean annual temperature is about 60 degrees F.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, thermic Lithic Haplocalcids

TYPICAL PEDON: Hiddensun very gravelly fine sandy loam, rangeland and wildlife habitat. (Colors are for dry soil unless otherwise noted.) The soil surface is covered by approximately 45 percent pebbles, 10 percent cobbles and 1 percent stones.

A--0 to 3 inches; light yellowish brown (10YR 6/4) very gravelly fine sandy loam, dark yellowish brown (10YR 4/4) moist; moderate thin platy structure; soft, very friable, nonsticky and nonplastic; many very fine and common fine roots; common very fine and fine interstitial pores; 45 percent pebbles, 10 percent cobbles and 1 percent stones; violently effervescent; moderately alkaline (pH 8.4) abrupt smooth boundary. (2 to 5 inches thick)

Bk1--3 to 8 inches; light yellowish brown (10YR 6/4) very cobbly fine sandy loam, dark yellowish brown (10YR 4/4) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine and fine roots; common very fine and fine interstitial pores; common fine calcium carbonate coats and pendants on rock fragments; 20 percent pebbles and 30 percent cobbles; violently effervescent; moderately alkaline (pH 8.4) abrupt wavy boundary.

Bk2--8 to 15 inches; very pale brown (10YR 7/3) extremely cobbly fine sandy loam, yellowish brown (10YR 5/4) moist; massive; soft, very friable, nonsticky and nonplastic; common very fine and fine roots; common very fine and fine interstitial pores; many coarse calcium carbonate coats and soft masses on rock fragments; 10 percent pebbles and 50 percent cobbles; violently effervescent; strongly alkaline (pH 8.6) abrupt irregular boundary. (The combined thickness of the Bk horizons is 9 to 18 inches.)

R--15 inches; hard fractured basalt bedrock; lime and few roots in fractures.

TYPE LOCATION: Clark County, Nevada; approximately 4 miles northeast of Jean Lake (dry lake) and 2.7 miles southwest of Erie railroad siding; about 730 feet east and 1,790 feet north of the southwest corner of section 19, T. 24 S., R. 61 E.; USGS Hidden Valley, NV 7.5 minute topographic quadrangle; 35 degrees, 50 minutes and 31 seconds north latitude and 115 degrees, 12 minutes and 3 seconds west longitude; UTM 11, 662487e, 3967913n; NAD 83.

RANGE IN CHARACTERISTICS:

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

Soil temperature - 59 to 65 degrees F.

Depth to calcic horizon - 2 to 5 inches.

Depth to lithic contact - 14 to 20 inches.

Control section - Rock fragments: 40 to 65 percent, dominated by cobbles.

Percent clay: 6 to 12 percent.

Effervescence: Strongly effervescent or violently effervescent.

A horizon - Chroma: 3 or 4 dry or moist.
Calcium carbonate equivalent in the fine earth fraction: 5 to 10 percent.

Bk horizons - Value: 3 through 5 moist, 6 or 7 dry.
Chroma: 3 or 4 dry or moist.
Structure: subangular blocky or massive.
Consistence: Nonsticky and slightly sticky.
Reaction: Moderately alkaline or strongly alkaline.
Calcium carbonate equivalent in the fine earth fraction: 15 to 30 percent.

COMPETING SERIES: This is the Hobog (UT) series. Hobog soils have hue of 5YR or 7.5YR and do not receive the 10 to 20 days of summer precipitation.

GEOGRAPHIC SETTING: Hiddensun soils are on mountains. These soils formed in residuum from volcanic rocks influenced by calcareous loess. Slope ranges from 8 to 50 percent. Elevations are 3,000 to 4,400 feet. The climate is hot and arid with warm, moist winters and hot, dry summers. The mean annual precipitation is 5 to 7 inches; mean annual temperature is 57 to 63 degrees F., and the frost-free season is 180 to 240 days.

GEOGRAPHICALLY ASSOCIATED SOILS: This is the Haleburu and Nipton series. Haleburu and Nipton soils do not have a calcic horizon and is less than 14 inches deep to bedrock.

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

USE AND VEGETATION: These soils are used for rangeland and wildlife habitat. The present vegetation is mainly big galleta, white bursage, winterfat and Nevada ephedra.

DISTRIBUTION AND EXTENT: Mojave Desert of southern Nevada. MLRA 30. These soils are not extensive.

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

SERIES ESTABLISHED: Clark County Area, Nevada, 2006. Proposed in Clark County, Nevada, 1994. The name is coined from the adjacent Hidden Valley.

REMARKS: Soil classification by Taxonomy amendment 17 will be Lithic Haplocalcids.

Diagnostic horizons and features recognized in this pedon are:

Ochric epipedon - 0 to 3 inches (A horizon).

Calcic horizon - 3 to 15 inches (Bk1 and Bk2 horizons).

Lithic contact - 15 inches (R layer).

Particle-size control section - 10 to 15 inches (Part of the Bk2 horizon).

Responsibility for this series was transferred from Davis to Phoenix 4/2015. The last revision to the series was 7/2006. ET

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National Cooperative Soil Survey
U.S.A.