LOCATION CIRCULAR                AZ

Established Series
WJ/RKS/DWD/HCD
04/2015

CIRCULAR SERIES

The Circular series consists of very deep, somewhat excessively drained soils that formed in mixed alluvium on basin floors. Slopes range from 1 to 4 percent. The mean annual precipitation is about 10 inches and the mean annual air temperature is about 65 degrees F.

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, calcareous, thermic Typic Torriorthents

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

A--0 to 2 inches; yellowish brown (10YR 5/4) sandy loam, brown (10YR 4/3) moist; weak fine granular structure; soft, very friable, nonsticky and nonplastic; few very fine roots; few very fine and fine irregular pores; 1 percent gravel; strongly effervescent, 5 percent calcium carbonate equivalent; moderately alkaline (pH 8.4); abrupt smooth boundary. (1 to 3 inches thick)

C1--2 to 35 inches; yellowish brown (10YR 5/4) sandy loam, dark yellowish brown (10YR 4/4) moist; massive; slightly hard, very friable, nonsticky and nonplastic; common fine and medium roots; common very fine and fine tubular pores; few animal burrows; violently effervescent, 10 percent calcium carbonate equivalent; moderately alkaline (pH 8.4); clear wavy boundary. (12 to 40 inches thick)

C2--35 to 44 inches; yellowish brown (10YR 5/4) sandy loam, dark yellowish brown (10YR 4/4) moist; massive; slightly hard, very friable, nonsticky and nonplastic; common fine and medium roots; common very fine and fine tubular pores; 5 percent gravel; violently effervescent, 7 percent calcium carbonate equivalent; strongly alkaline (pH 8.6); abrupt smooth boundary. (4 to 13 inches thick)

C3--44 to 60 inches; yellowish brown (10YR 5/4) loamy sand, brown (7.5YR 4/4) moist; massive; slightly hard, very friable, nonsticky and nonplastic; common fine and medium roots; common very fine and fine irregular pores; 10 percent gravel; strongly effervescent, 8 percent calcium carbonate equivalent; moderately alkaline (pH 8.4).

TYPE LOCATION: Mohave County, Arizona; located at a latitude of 35 degrees, 38 minutes, 06 seconds North and longitude of 113 degrees, 57 minutes, 26 seconds West; about 700 feet North and 800 feet West of the southeast corner of section 14, T. 26 N., R. 16 W. Gila and Salt River Base Meridian.

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 soil moisture regime.

Soil temperature: 59 to 72 degrees F.

Reaction: moderately or strongly alkaline

Clay content in control section: 5 to 18 percent

Rock fragments: less than 35 percent throughout the profile

Organic matter: less than 1 percent

Texture below 40 inches: loamy sand, sandy loam, loam


A horizon

Value: 5 or 6 dry, 4 or 5 moist

Chroma: 3 or 4 dry or moist


C horizons

Hue: 10YR, 7.5YR

Value: 5 or 6 dry, 4 or 5 moist

Chroma: 3 or 4, dry or moist

Reaction: moderately or strongly alkaline

COMPETING SERIES: These are the Bitterwater (CA), Elkhills (CA), Granitepass(CA), ( Herbel (NM), Kimberlina (CA), Machone (CA), McCullough (NV) and Seaman (NV) soils. Bitterwater soils have bedrock at depths of 40 to 60 inches. Elkhills, Kimberlina and Machone soils are dry in all parts of the soil moisture control section from May - December. Granitepass soils have greater than 35 percent coarse fragments in the surface horizons. Herbel soils are intermittently moist in some part of the soil moisture control section for more than 20 days cumulative during July - September. McCullough soils have sandy textures within 40 inches of the surface. Seaman soils have volcanic ash within the profile.

GEOGRAPHIC SETTING: Circular soils are on basin floors at elevations of 2,500 to 4,000 feet. Slopes range from 1 to 4 percent. These soils formed in mixed alluvium. The mean annual precipitation is 9 to 12 inches. The mean annual air temperature is 57 to 70 degrees F. The frost-free period is 180 to 280 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Lostman, Antares, Dusty and Cod soils. Lostman soils have a cambic horizon. Antares and Dusty soils have argillic horizons. Cod soils have a calcic horizon.

DRAINAGE AND PERMEABILITY: Somewhat excessively drained; low runoff; moderately rapid permeability.

USE AND VEGETATION: Circular soils are used for livestock grazing and wildlife habitat. Vegetation includes big galleta, alkali sacaton, Anderson wolfberry and shadscale.

DISTRIBUTION AND EXTENT: Northwestern Arizona. Circular soils are of limited extent. MLRA is 30.

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

SERIES ESTABLISHED: Mohave County, Arizona; Soil survey of Mohave County, Arizona, Central Part; 2005.

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

Ochric epipedon - The zone from 0 to 2 inches (A horizon)

Entisol feature - The absence of diagnostic subsurface horizons
Classified according to Keys to Soil Taxonomy Ninth Edition, 2003.

Responsibility for this series was transferred from Davis to Phoenix 4/2015. The last revision to the series was 1/2005. ET

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National Cooperative Soil Survey
U.S.A.