LOCATION AVONDA AZEstablished Series
TAXONOMIC CLASS: Fine-loamy over sandy or sandy-skeletal, mixed, superactive, calcareous, hyperthermic Typic Torrifluvents
TYPICAL PEDON: Avonda clay loam, cultivated. (Colors are for dry soil unless otherwise noted.)
Ap--0 to 13 inches; grayish brown (10YR 5/2) clay loam, very dark grayish brown (10YR 3/2) moist; weak fine and medium granular structure; slightly hard, friable, sticky and plastic; common fine and very fine roots; few fine and very fine tubular and few medium interstitial pores; slightly effervescent; moderately alkaline (pH 8.2); abrupt smooth boundary. (8 to 15 inches thick)
C1--13 to 27 inches; light brown (7.5YR 6/4) loam, brown (7.5YR 4/4) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; common very fine and fine roots; common very fine and fine tubular and common very fine interstitial pores; common very fine mica flakes; common very thin strata of both finer and coarser textured material; strongly effervescent; moderately alkaline (pH 8.3); clear smooth boundary. (12 to 24 inches thick)
2C2--27 to 60 inches; pinkish gray (7.5YR 6/2) and light brown (7.5YR 6/4) loamy coarse sand, brown (7.5YR 5/4) moist; single grained; loose, nonsticky and nonplastic; few very fine roots; many fine and coarse interstitial pores; few fine gravel; strongly effervescent; moderately alkaline (pH 8.2).
TYPE LOCATION: Maricopa County, Arizona; approximately 1 mile east of Buckeye, Arizona; 70 feet south and 530 feet west of E1/4 corner of sec. 4, R. 1 S., R. 3 W.
RANGE IN CHARACTERISTICS:
Depth to the sand or gravelly sand: ranges from 20 to 39 inches but averages 24 to 30 inches.
Soil moisture: dry more than 3/4 of the time with the driest periods being during the spring and autumn. Typic aridic moisture regime.
Mean annual soil temperature: about 72 degrees to 80 degrees F.
Calcium carbonate: The soil is calcareous throughout; mycelia-like lime veins and lime filaments are common in the C horizon
Stratification: The profile is generally stratified with thin layers of finer or coarser textured material.
A horizon
Organic matter: usually 1 percent or more
Hue: 7.5YR or 10YR
Value: 4 or 5 dry and 3 moist
Chroma: 2 or 3 dry and moist.
C1 horizon
Hue: 7.5YR or 10YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 4 or 3 dry and moist
Texture: loam, silt loam or very fine sandy loam
Clay content: averages more than 18 percent
2C2 horizon
Hue: 7.5YR or 10YR
Value: 6 or 7 dry, 5 or 6 moist
Chroma: 2 to 4 dry and moist
Texture: loamy coarse sand, loamy sand, loamy fine sand or sand, and is gravelly or very gravelly in some pedons
Stratification: thin strata of finer material are common.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: The Avonda soils are on fans and flood plains. They formed in mixed alluvium from a variety of rocks. Slopes range from 0 to 1 percent. Elevations are 200 to 1,400 feet. Slopes range from 0 to 1 percent. Elevations are 200 to 1,400 feet. These soils are in a warm, arid and semiarid climate. The mean annual precipitation ranges from 3 to 10 inches, and the mean annual temperature ranges from 67 degrees to 75 degrees F. The frost-free season is about 250 to 300 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Agualt, Avondale, Gilman and Glenbar soils and the Cashion, Gadsden and Vint soils. Cashion soils have a clayey over loamy control section. Gadsden soils have a fine textured control section. Vint soils have a coarse-textured control section.
DRAINAGE AND PERMEABILITY: Well drained, medium to slow runoff; moderately slow permeability.
USE AND VEGETATION: Used for irrigation and rangeland. Irrigated areas are used for production of cotton, alfalfa, small grains, sugar beets, vegetables and safflower. Nonirrigated areas are used for limited grazing. Native vegetation is creosotebush, salt cedar, mesquite, annual grasses and weeds.
DISTRIBUTION AND EXTENT: Southern and central Arizona, but mainly in Maricopa, Yuma and Pinal Counties. Avonda soils are of small extent. MLRA 40.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Central Maricopa County Area, Arizona, 1972.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - 0 to 13 inches (Ap horizon)
Strongly contrasting material 27 inches (the boundary between the C1 (loam) and 2C2 (loamy coarse sand) horizons)
Fluvent feature an irregular decrease in organic matter is inferred from the stratification of finer and coarser textures
Classified according to Keys to Soil Taxonomy Ninth Edition, 2003