LOCATION RUDD AZ+NMEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic Lithic Calciustolls
TYPICAL PEDON: Rudd very gravelly loam - rangeland. (Colors are for dry soil unless otherwise noted.)
A--0 to 2 inches; grayish brown (10YR 5/2) very gravelly loam, dark brown (7.5YR 3/2) moist; weak fine granular structure; soft, friable, slightly sticky and slightly plastic; many fine and medium roots; many fine irregular pores; 40 to 50 percent gravel; strongly effervescent; moderately alkaline (pH 8.2); clear smooth boundary. (1 to 4 inches thick)
Bk1--2 to 10 inches; dark grayish brown (10YR 4/2) very gravelly loam, dark brown (7.5YR 3/2) moist; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and plastic; many fine and medium roots; few fine tubular and many fine irregular pores; more than 35 percent gravel; strongly effervescent; moderately alkaline (pH 8.2); clear wavy boundary. (4 to 9 inches thick)
Bk2--10 to 13 inches; grayish brown (10YR 5/2) gravelly loam, dark brown (10YR 3/3) moist; massive; slightly hard, friable, slightly sticky and plastic; many fine and medium roots; many fine irregular pores; 20 to 35 percent gravel; violently effervescent; moderately alkaline (pH 8.2); abrupt wavy boundary. (1 to 7 inches thick)
2R--13 inches; basalt; calcium carbonate coatings on rock surfaces and in joints.
TYPE LOCATION: Apache County, Arizona; about 5.5 miles northwest of Springerville, Arizona; 1,848 feet north and 396 feet east of the center of section 11, T. 9 N., R. 28 E.
RANGE IN CHARACTERISTICS:
Soil Moisture: Intermittently moist in some part of the soil moisture control section during July-September and December-February. Driest during May and June. Ustic aridic soil moisture regime.
Rock Fragments: 20 to 60 percent gravel and cobble-size; averages more than 35 percent in the control section
Soil Temperature: 47 to 57 degrees F.
Calcium carbonate equivalent: 15 to 50 percent; averages 15 to 40 percent in the control section
Depth to bedrock: 6 to 20 inches
Clay content: Averages more than 18 percent in the control section
A horizon
Hue: 7.5YR, 10YR
Value: 4 or 5 dry, 2 or 3 moist
Chroma: 1 through 3, dry or moist
B horizon
Hue: 7.5YR, 10YR
Value: 3 through 7 dry, 2 through 5 moist
Chroma: 1 through 4, dry or moist
Texture: Loam, clay loam
COMPETING SERIES: These are the Desario (NM) and Yumtheska (AZ) series. Desario soils formed over limestone of the Madera formation and have an aridic ustic soil moisture regime. Yumtheska soils formed on limestone and have an aridic ustic soil moisture regime.
GEOGRAPHIC SETTING: Rudd soils are on basalt mesas and lava flows and have slopes of 0 to 45 percent. These soils formed in alluvium from basalt and closely related materials. Elevations range from 5,200 to 7,600 feet. The mean annual precipitation is 10 to 14 inches. The mean annual air temperature is 45 to 55 degrees F. The frost-free period is 120 to 160 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Springerville and Thunderbird soils. Springerville and Thunderbird soils are fine-textured.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; moderate permeability.
USE AND VEGETATION: Rudd soils are used for livestock grazing and wildlife habitat. The present vegetation is black, blue and sideoats gramas, three-awn, galleta, sand dropseed, snakeweed, wolftail and annuals.
DISTRIBUTION AND EXTENT: Northern Arizona. This series is of moderate extent. MLRAs 35 & 36.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Apache County, Arizona, Central Part; 1971.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from 0 to 13 inches (A, Bk1, Bk2 horizons)
Calcic horizon - The zone from 2 to 13 inches (Bk1, Bk2 horizons)
Lithic contact - The boundary at 13 inches (2R horizon)