LOCATION CARRIZO CA+AZ NV

Established Series
Rev. LJL/PBF/CAH/ET
08/2013

CARRIZO SERIES

The Carrizo series consists of very deep, excessively drained soils formed in mixed igneous alluvium. Carrizo soils are on numerous landforms on flood plains, fan piedmonts and bolson floors. Slopes range from 0 to 15 percent. The mean annual precipitation is about 100 millimeters (4 inches) and the mean annual air temperature is about 21.5 degrees C (71 degrees F).

TAXONOMIC CLASS: Sandy-skeletal, mixed, hyperthermic Typic Torriorthents

TYPICAL PEDON: Carrizo extremely gravelly sand, rangeland and wildlife habitat. (Colors are for dry soil unless otherwise noted.) The soil surface is covered by approximately 70 percent gravel, 6 percent cobbles and 4 percent stones.

A -- 0 to 5 centimeters (0 to 2 inches); pale brown (10YR 6/3) extremely gravelly sand, brown (10YR 4/3) moist; massive; slightly hard, very friable, nonsticky and nonplastic; few very fine roots; common very fine interstitial pores; 55 percent gravel, 6 percent cobbles and 4 percent stones; slightly effervescent; moderately alkaline (pH 8.0); abrupt smooth boundary. (2.5 to 10 centimeters thick)

C -- 5 to 152 centimeters (2 to 60 inches); pale brown (10YR 6/3) stratified extremely gravelly and very gravelly coarse sand, brown (10YR 4/3) moist; massive to single grain; soft, slightly hard, or loose, very friable, nonsticky and nonplastic; common very fine and few fine roots; many very fine and few fine and medium interstitial pores; averages 55 percent gravel, 10 percent cobbles and 5 percent stones; very slightly effervescent and slightly effervescent; moderately alkaline (pH 8.4) and slightly alkaline (pH 7.8).

TYPE LOCATION: San Bernardino County, California; approximately 18.5 kilometers (11.5 miles) southwest of Amboy; about 610 meters (2,000 feet) south and 305 meters (1,000 feet) west of the NE corner of section 18, T. 4 N., R. 11 E., San Bernardino Base and Meridian; USGS Lead Mountain Northeast, CA 7.5 minute topographic quadrangle; 34 degrees, 26 minutes, 11.1 seconds north latitude and 115 degrees, 51 minutes, 47.8 seconds west longitude; UTM 11S, 0604440e 3810938n (DTM: NAD83).

RANGE IN CHARACTERISTICS:

Soil moisture control section: usually dry, moist in some parts for short periods during winter and early spring and for 10 to 20 days cumulative between July and September following convection storms. The soils have a typic-aridic soil moisture regime.

Soil temperature: 22 to 25 degrees C (72 to 77 degrees F)
Surface rock fragments: 25 to 100 percent
25 to 95 percent gravel
0 to 40 percent cobbles
0 to 25 percent stones
0 to 2 percent boulders.

Control section
Rock fragments: averages 35 to 80 percent, gravel, cobbles and stones
Clay content: averages 0 to 8 percent
Effervescence: noneffervescent through violently effervescent
Reaction: slightly acid through strongly alkaline

A horizon
Hue: 7.5YR, 10YR, 2.5Y
Value: 4 to 7 dry, 2 to 6 moist
Chroma: 2 to 6 dry, 2 to 4 moist
Clay content: 1 to 10 percent
Texture of the fine earth fraction: coarse sand, sand, loamy sand, loamy coarse sand, sandy loam or fine sandy loam
Rock fragments: 5 to 65 percent, with 5 to 65 percent gravel, 0 to 25 percent cobbles and 0 to 5 percent stones
Effervescence: noneffervescent through violently effervescent
Reaction: slightly acid through strongly alkaline

C horizons
Hue: 7.5YR, 10YR, 2.5Y
Value: 4 to 7 dry, 2 to 6 moist
Chroma: 2 to 6 dry, 2 to 4 moist
Clay content: averages 0 to 8 percent, ranges from 0 to 12 percent
Texture of the fine earth fraction: coarse sand, sand, loamy coarse sand or loamy sand. Some pedons have thin strata of fine sand, loamy fine sand or sandy loam
Rock fragments: 10 to 85 percent, with 10 to 80 percent gravel with more than 50 percent as medium or coarse-sized, 0 to 25 percent cobbles and 0 to 10 percent stones
Effervescence: noneffervescent through violently effervescent
Reaction: slightly acid through strongly alkaline
Silica: 0 to 25 percent as films on rock fragments

COMPETING SERIES: These are the Carrwash (NV), Chemwash (CA), Descent (CA), Goldenhills (CA), and Rizzo (CA) series. Carrwash and Chemwash soils are dominated by 2 to 5 millimeter (fine) gravel. Chemwash and Rizzo soils have mean annual soil temperatures that average greater than 25 degrees C, do not receive appreciable summer precipitation, and are generally dry throughout the moisture control section for most of the year. Descent soils have a calcium carbonate equivalent of 5 percent or greater throughout the profile without a diagnostic calcic horizon and are dominated by channers and flagstones. Goldenhills soils are formed in colluvium and residuum, have a surface C horizon with more than 80 percent rock cover, and are deep to a lithic contact.

GEOGRAPHIC SETTING: Carrizo soils are on numerous landforms on flood plains, fan piedmonts and bolson floors. Slopes range from 0 to 15 percent. The soils formed in mixed igneous alluvium. Elevations are -82 to 793 meters (-270 to 2,600 feet). The climate is arid with hot, dry summers and warm, moist winters. Precipitation is greatest in the winter with a lesser secondary peak in the summer. The mean annual precipitation is 75 to 175 millimeters (3 to 7 inches); mean January temperature is 12 degrees C (53 degrees F); mean July temperature is 35 degrees C (95 degrees F); mean annual air temperature is 20 to 23 degrees C (68 to 73.5 degrees F), and the frost-free season is 300 to 340 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bristolake, Clegorpass, Heleweiser, Pintobasin, and Riverbend soils. Bristolake soils are on nearby fan skirts and lower fan aprons, have a sandy particle size control section and are slightly saline with an SAR of 5 to 13 in the control section. Clegorpass and Heleweiser soils are on nearby fan remnants and have loamy-skeletal particle size control sections. In addition, Clegorpass soils have an argillic horizon and Heleweiser soils have a calcic horizon. Pintobasin soils are on similar landscape positions and are sandy throughout the particle size control section. Riverbend soils are on more stable landforms and have a calcic horizon.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Excessively drained; negligible to low runoff; high saturated hydraulic conductivity.

USE AND VEGETATION: These soils are used for rangeland, recreation and wildlife habitat. Present vegetation is creosote bush, burrobush, burrobrush and range ratany.

DISTRIBUTION AND EXTENT: Mojave Desert of southeastern California, western Arizona, and southern Nevada; MLRA 30. These soils are extensive.

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

SERIES ESTABLISHED: Imperial County (El Centro Area), California; 1918.

REMARKS: The type location was relocated in 2006 to the Marine Corps Air Ground Combat Center, Twentynine Palms, California to better represent the series concept. The series has been overused throughout the Southwestern deserts including areas with precipitation ranging from 2 to 12 inches. Soils with extreme aridic moisture regimes should consider using the Rizzo series proposed for use in the Lower Colorado Desert (MLRA 31) with a moisture control section that is typically dry throughout for most of the year. New series should be proposed for the high precipitation zones. Use in MLRA 40 should also be reevaluated.

Diagnostic horizons and features in this pedon include:
Ochric epipedon - the zone from a depth of 0 to 18 centimeters (A and part of the C horizons).
Particle size control section - the zone from a depth of 25 to 100 centimeters (part of the C horizon).

Revised for the correlation of SDJR - MLRA 30 - Carrizo-Riverwash complex 3 to 8 percent slopes, 03/13, LJG2
Classified according to Soil Taxonomy, Second Edition, 1999; Keys to Soil Taxonomy, 11th Edition, 2010

National Cooperative Soil Survey
U.S.A.