LOCATION CHERIONI AZEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, hyperthermic, shallow Typic Haplodurids
TYPICAL PEDON: Cherioni very gravelly fine sandy loam - rangeland. (Colors are for dry soil unless otherwise noted.) 60 percent of surface covered with basalt gravel and cobble.
A--0 to 2 inches; light brown (7.5YR 6/4) very gravelly very fine sandy loam, brown (7.5YR 4/4) moist; weak thin platy structure; slightly hard, very friable, slightly sticky and slightly plastic; few fine roots; many fine irregular pores; 40 percent fine and medium gravel; slightly effervescent; moderately alkaline (pH 8.1); abrupt wavy boundary. (1 to 3 inches thick)
Bk1--2 to 6 inches; light brown (7.5YR 6/4) very gravelly very fine sandy loam, reddish brown (5YR 5/4) moist; massive; slightly hard, very friable, slightly sticky and slightly plastic; few fine roots; many fine irregular pores; 35 percent fine and medium gravel; many fine distinct calcium carbonate masses; violently effervescent; moderately alkaline (pH 8.2); abrupt wavy boundary. (2 to 8 inches thick)
Bk2--6 to 9 inches; light brown (7.5YR 6/4) very gravelly very fine sandy loam, yellowish red (5YR 4/6) moist; massive; slightly hard, very friable, slightly sticky and slightly plastic; few fine and medium roots; many fine irregular pores; 50 percent medium and coarse calcium carbonate coated gravel; violently effervescent; moderately alkaline (pH 8.3); abrupt wavy boundary. (2 to 9 inches thick)
2Bkqm--9 to 11 inches; silica-calcium carbonate cemented duripan with laminar layer on the upper surface; extremely hard; strongly effervescent; abrupt wavy boundary. (1 to 8 inches thick)
3R--11 inches; extremely hard tuffaceous conglomerate with calcium carbonate coatings on upper surface.
TYPE LOCATION: Pima County, Arizona; Organ Pipe Cactus National Monument; 2000 feet west and 1000 feet north of the southeast corner of section 19, T. 14 S., R. 6 W.
RANGE IN CHARACTERISTICS: Latitude 32 degrees, 11 minutes, 20 seconds N. and longitude 112 degrees, 55 minutes, 18 seconds W., and NAD 83.
Soil moisture - Intermittently moist in some part of the soil moisture control section during December - February and for more than 20 days cumulative during July - September. Driest during May and June. Typic aridic soil moisture regime.
Rock fragments - 35 to 80 percent in the control section
Depth to duripan - 5 to 20 inches; has thin (1/4 to 2 inches) laminar cap in most places
Depth to bedrock - 6 to 20 inches
Texture- Very fine sandy loam, fine sandy loam, sandy loam, loam (10 to 20 percent clay)
A horizon
Hue: 7.5YR, 10YR
Value: 6, 7 or 8 dry, 3, 4, 5 or 6 moist
Chroma: 2, 3, or 4 dry, 2, 3, 4, or 6 moist
Organic matter: Less than 1 percent
B horizons
Hue: 5YR, 7.5YR, 10YR
Value: 5, 6 or 7 dry, 4 or 5 moist
Chroma: 4 dry, 4 or 6 moist
Calcium carbonate: coated gravel, gravel-size hardpan fragments, and soft masses
COMPETING SERIES: These are the Cheme (NV), Cipriano (AZ) and Tyro (AZ) series. Cipriano soils do not have bedrock within a depth of 40 inches. Cheme and Tyro soils are intermittently moist in some part of the soil moisture control section for less than 20 days cumulative between July and September.
GEOGRAPHIC SETTING: Cherioni soils are on hills and fan terraces. Slopes are dominantly 1 to 15 percent but range from 0 to 70 percent. Elevations range from 150 to 3000 feet. These soils formed in fan alluvium on pyroclastic and metamorphic rocks. The climate is hot, arid and continental. Mean annual precipitation is 2 to 10 inches; about one-half of which falls during summer thunderstorms during the months of July, August and September. Average January air temperature is about 51 degrees F. and the average July air temperature is about 91 degrees F. Mean annual air temperature is 67 to 76 degrees F. The frost-free period is about 240 to 350 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Antho, Gachado, Gilman, Growler, Harqua and Pinamt soils and the competing Cipriano soils. Antho and Gilman soils have less than 35 percent coarse fragments in the control section and do not have a duripan. Gachado, Growler, Harqua and Pinamt soils have argillic horizons and do not have a duripan.
DRAINAGE AND PERMEABILITY: Somewhat excessively drained; medium to rapid runoff; moderate permeability.
USE AND VEGETATION: Used for livestock grazing. Present vegetation is creosotebush, paloverde, saguaro, cholla, ocotillo, triangleleaf bursage and ratany.
DISTRIBUTION AND EXTENT: Southern Arizona. Cherioni soils are extensive. Total extent is about 180,000 acres. MLRA is 40.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Pima County, Arizona; Organ Pipe Cactus National Monument Survey Area; 1971.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - the zone from 0 to 2 inches (A horizon)
Duripan- the zone from 9 to 11 inches (2Bkqm horizon)
Lithic Contact - the boundary at 11 inches (3R horizon)
Classified according to Soil Taxonomy, Second Edition, 1999; Keys to Soil Taxonomy, Tenth Edition, 2006
Revised for the correlation of AZ661, 12/2008, WWJ