LOCATION CUPEL                   AZ

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

CUPEL SERIES

The Cupel series consists of shallow, well drained soils on hills and mountains. These soils are formed in colluvium and alluvium from rhyolite and basalt. Slopes range from 35 to 65 percent. The mean annual precipitation is about 10 inches. The mean annual air temperature is about 62 degrees F.

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

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

A--0 to 2 inches; yellowish brown (10YR 5/4) very gravelly sandy loam, dark yellowish brown (10YR 4/4) moist; moderate fine granular structure; soft, very friable, nonsticky and nonplastic; common very fine roots; few very fine irregular pores; 35 percent gravel, 15 percent cobble; noneffervescent; slightly alkaline (pH 7.6); abrupt smooth boundary. (1 to 3 inches thick)

Bw1--2 to 12 inches; yellowish brown (10YR 5/4) extremely gravelly sandy clay loam, dark yellowish brown (10YR 4/4) moist; weak fine subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; common very fine and fine roots; common very fine irregular pores; 50 percent gravel, 20 percent cobble; noneffervescent; slightly alkaline (pH 7.6); clear wavy boundary. (2 to 10 inches thick)

Bw2--12 to 17 inches; yellowish brown (10YR 5/4) extremely gravelly sandy clay loam, dark yellowish brown (10YR 4/4) moist; weak fine subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; few fine and medium roots; common fine irregular pores; 50 percent gravel, 20 percent cobble; strongly effervescent; slightly alkaline (pH 7.8). (4 to 12 inches thick)

2R--17 inches; rhyolite.

TYPE LOCATION: Detrital Valley, Mohave County, Arizona; Latitude of 35 degrees, 22 minutes, 37 seconds North, and longitude of 114 degrees, 24 minutes, 51 seconds West. About 400 feet west and 4,100 feet south of the northeast corner of section 16, T. 23 N., R. 20 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: 61 to 66 degrees F.


Rock fragments: 35 to 70 percent gravel, and 5 to 20 percent cobble

Depth to bedrock: 10 to 20 inches

Reaction: slightly or moderately alkaline

Clay content: averages 20 to 27 percent in the particle-size control section

Effervescence: Typically slight or strong in the subsoil. Can range from noneffervescent to violent

Organic matter: less than one percent.


A horizon

Hue: 7.5YR, 10YR

Value: 5 or 6 dry, 4 or 5 moist

Chroma: 4 or 5, dry or moist


B horizons

Hue: 7.5YR, 10YR

Value: 5 or 6 dry, 4 or 5 moist

Chroma: 4 or 5, dry or moist

Effervescence: slight to strong

Texture: clay loam, sandy clay loam

COMPETING SERIES: These are the Garr (NV), Garzona (AZ), Pacific Mesa (CA) and Pulsipher (NV) series. Garr and Pulsipher soils contain less than 18 percent clay in the control section. Garzona soils are intermittently moist in some part of the soil moisture control section for more than 20 days cumulative during July - September. Pacific Mesa soils have accumulations of calcium carbonate and silica in the control section.

GEOGRAPHIC SETTING: Cupel soils are on hills and mountains. Elevations are 3,500 to 4,500 feet. Slopes range from 35 to 65 percent. These soils are formed in colluvium and alluvium from mixed volcanics. The mean annual precipitation is 8 to 12 inches. The mean annual air temperature is 59 to 64 degrees F. The frost-free period is 200 to 280 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Zibate, Mayswell, Detrital, Nealy and Jagerson soils. Zibate and Mayswell soils are shallow over bedrock. Detrital and Jagerson soils are very deep. Nealy soils are moderately deep over a hardpan.

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

USE AND VEGETATION: Used for livestock grazing and wildlife habitat. Vegetation includes flattop buckwheat, big galleta, California juniper, and desert needlegrass.

DISTRIBUTION AND EXTENT: Northwestern Arizona. Cupel soils are of moderate 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. The name is from a mine within the survey area.

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

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

Cambic horizon - The zone from 2 to 17 inches (Bw1, Bw2 horizons)

Lithic contact - The boundary at 17 inches (2R horizon)

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

---

National Cooperative Soil Survey
U.S.A.