LOCATION GOLDROAD                AZ+CA NV

Established Series
Rev. WJ/PH/PDC/ET
04/2015

GOLDROAD SERIES

The Goldroad series consists of very shallow and shallow, somewhat excessively drained soils that formed in alluvium, residuum, and colluvium from granite and metamorphic rocks. Goldroad soils are on hills and mountains and have slopes of 15 to 75 percent. The mean annual precipitation is about 6 inches and the mean annual air temperature is about 74 degrees F.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, calcareous, hyperthermic Lithic Torriorthents

TYPICAL PEDON: Goldroad very cobbly sandy loam - rangeland. (Colors are for dry soil unless otherwise noted)

A--0 to 1 inch; yellowish brown (10YR 5/4) very cobbly sandy loam, brown (10YR 4/3) moist; weak fine granular structure; soft, very friable, nonsticky and nonplastic; common very fine roots; common very fine tubular pores; 30 percent cobble and 25 percent gravel; strongly effervescent; moderately alkaline (pH 8.0); abrupt smooth boundary. (1 to 4 inches thick)

Bw--1 to 8 inches; yellowish brown (10YR 5/4) very cobbly coarse sandy loam, brown (10YR 4/3) moist; weak fine subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; common very fine roots; common very fine tubular pores; 30 percent cobble and 25 percent gravel; strongly effervescent; moderately alkaline (pH 8.0); abrupt wavy boundary. (2 to 18 inches thick)

2R--8 inches; granite bedrock.

TYPE LOCATION: Mohave County, Arizona. 12 miles southeast of Hoover Dam; about 70 feet south and 650 feet west of the northeast corner of section 5, T. 28 N., R. 22 W. Gila and Salt River Base Meridian. 35 degrees, 51 minutes, 4 seconds north latitude and 114 degrees, 38 minutes, 56 seconds west longitude.

RANGE IN CHARACTERISTICS:

Soil Moisture: Intermittently moist in some part of the soil moisture control section during December - February and for less than 20 days cumulative during July - September. Driest during May and June. Typic aridic moisture regime.

Soil Temperature: 72 to 80 degrees F.

Rock fragments: 35 to 75 percent granitic gravel and cobbles. The gravels are dominated by fragments ranging in diameter from 2 to 5 millimeters

Depth to bedrock: 4 to 20 inches

Reaction: slightly or moderately alkaline

Organic matter: Less than 1 percent

Calcium carbonate equivalent: 1 to 10 percent

Clay content: 5 to 18 percent

A horizon Hue: 10YR, 7.5YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 3 or 4, dry or moist

Bw or Bk horizons - Hue: 10YR, 7.5YR
Value: 5 or 6 dry, 4 through 6 moist
Chroma: 3 or 4, dry or moist
Texture: sandy loam, coarse sandy loam; dominantly coarse and very coarse in the sand fraction.
Consistence: Soft or slightly hard, dry.
Other features: Some pedons have thin coats of secondary calcium carbonate: on the undersides of rock fragments.

COMPETING SERIES: These are the Appleseed (AZ), Hyder (AZ), Quilotosa (AZ) Redneedle (NV) and Sunrock (AZ) series. Appleseed and Redneedle soils are not dominated by 2 to 5 millimeter gravels. In addition, Appleseed soils have a calcium carbonate equivalence ranging to 35 percent and formed in limestone. Redneedle soils have hue of 5YR and formed in sandstone conglomerate. Hyder and Quilotosa soils are moist in some part of the moisture control section for more than 20 days cumulative during July - September. Sunrock soils have control sections dominated by fine and medium sand and formed on volcanic rock.

GEOGRAPHIC SETTING: Goldroad soils are on hills and mountains at elevations of 490 and up to 3,500 feet on south facing aspects. Slopes range from 15 to 75 percent. They formed in alluvium, residuum, and colluvium from granite and metamorphic rocks. The climate is low-latitude desert, with mild winters and very hot summers. Precipitation is greatest in the winter with a lesser secondary peak in the summer, typical of the Mojave Desert. The mean annual precipitation is 2 to 8 inches; mean annual air temperature is 69 to 78 degrees F, and the frost-free period is 280 to 360 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Carrizo, Haleburu, Huevi and Seanna soils. Carrizo and Huevi soils are very deep. Haleburu soils have a thermic soil temperature regime. Seanna soils have a thermic soil temperature regime and a paralithic contact.

DRAINAGE AND PERMEABILITY: Somewhat excessively drained; medium to very high runoff; moderately rapid permeability over bedrock.

USE AND VEGETATION: Used for recreation and wildlife habitat. Present vegetation is creosotebush, white bursage, white brittlebush, and red brome.

DISTRIBUTION AND EXTENT: Northwestern Arizona along the Colorado River, southern Nevada and in southeastern California in the Mojave Desert. The series is of large extent. MLRA is 30.

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

SERIES ESTABLISHED: San Bernadino County, California. Marine Corps Air Ground Combat Center, at Twentynine Palms Soil Survey Center.

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

Ochric epipedon: 0 to 7 inch (A and part of the Bw horizon)

Lithic contact: 8 inches (2R horizon)

Particle size control thickness: 0 to 8 inches (A and Bw horizons).

Classified according to Keys to Soil Taxonomy Ninth Edition, 2003.

Soils with depths greater than 10 inches do not have Bw horizons that qualify as Cambic horizons.

Series originally proposed in Mohave County, Arizona; Soil survey of Mohave County, Arizona, Central Part; 1993.

Responsibility for this series was transferred from Davis to Phoenix 4/2015. The last revision to the series was 2/2006. ET

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National Cooperative Soil Survey
U.S.A.