LOCATION THIMBLE                 AZ

Established Series
Rev. WJ/NLM/PDC
04/2011

THIMBLE SERIES

The Thimble series consists of shallow, well drained soils on hills. These soils formed in alluvium from basalt and pyroclastics. Slope is 1 to 65 percent. The mean annual precipitation is about 16 inches and the mean annual air temperature is about 50 degrees F.

TAXONOMIC CLASS: Clayey-skeletal, smectitic, mesic Aridic Lithic Argiustolls

TYPICAL PEDON: Thimble cobbly clay loam - woodland. (Colors are for dry soil unless otherwise noted.)

A--0 to 1 inch; brown (7.5YR 5/4) cobbly clay loam, brown (7.5YR 4/2) moist; strong fine granular structure; slightly hard, friable, sticky and plastic; common very fine roots; many very fine tubular pores; 20 percent cobble, 10 percent gravel; slightly alkaline (pH 7.6); clear wavy boundary. (1 to 6 inches thick)

Btk1--1 to 7 inches; brown (7.5YR 4/2) very cobbly clay, dark brown (7.5YR 3/2) moist; strong fine subangular blocky structure; very hard, very firm, very sticky and very plastic; common medium roots; many very fine tubular pores; many prominent clay films on ped faces and lining pores; thin lime coatings on the undersides of rock fragments; 20 percent cobble, 10 percent stones, 10 percent gravel; slightly alkaline (pH 7.8); clear wavy boundary. (4 to 10 inches thick)

Btk2--7 to 13 inches; brown (7.5YR 4/2) very cobbly clay, brown (7.5YR 4/2) moist; strong fine subangular blocky structure; very hard, very firm, very sticky and very plastic; common medium roots; many very fine tubular pores; many prominent clay films on ped faces and lining pores; lime coatings on the undersides of rock fragments; 20 percent cobble, 10 percent stones, 10 percent gravel; slightly alkaline (pH 7.8); clear wavy boundary. (2 to 8 inches thick)

Btk3--13 to 19 inches; brown (7.5YR 4/4) very cobbly clay loam, reddish brown (5YR 4/3) moist; moderate fine subangular structure; hard firm, sticky and plastic; common medium roots; many very fine tubular pores; few faint clay films on ped faces and lining pores; strongly effervescent, lime coatings on the undersides of rock fragments; 20 percent cobbles, 10 percent stones, 10 percent gravel; slightly alkaline (pH 7.8); abrupt smooth boundary. (0 to 7 inches thick)

2R--19 inches; basalt; discontinuous 1/8 to 3/4 inch hardpan; lime filling fractures.

TYPE LOCATION: Mohave County, Arizona; about 6 miles northeast of Mount Trumbull; 800 feet south and 800 feet west of the northeast corner of section 14, T. 35 N., R. 7 W; Latitude 36 degrees, 26 minutes, 19 seconds N., Longitude 113 degrees, 0 minutes, 22 seconds W.

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. Aridic ustic soil moisture regime.

Soil Temperature - 47 to 59 degrees F.

Rock Fragments - 35 to 75 percent cobble, gravel and stones

Carbonates - 1 to 10 percent calcium carbonate equivalent

Clay Content - 35 to 60 percent in the control section

Depth to Bedrock - 8 to 20 inches

A horizon
Hue: 7.5YR, 5YR, 10YR
Value: 3 through 5 dry, 2.5 through 4 moist
Chroma: 2 through 4, dry or moist

Bt horizon
Hue: 7.5YR, 5YR
Value: 3 through 6 dry, 3 through 5 moist
Chroma: 2 through 4, dry or moist
Texture: clay loam, clay

COMPETING SERIES: This is the Acti (NV) and Cedaran (NV) series. Acti and Cedaran soils do not have calcium carbonate within the control section.

GEOGRAPHIC SETTING: Thimble soils are on hills at elevations of 5,000 to 7,200 feet. They formed in alluvium from basalt and pyroclastics. Slopes range from 1 to 65 percent. The mean annual precipitation is 14 to 18 inches. The mean annual air temperature is 45 to 57 degrees F. The frost-free period is 120 to 180 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Lomaki, Showlow, Yumtheska and the Wukoki series. The Lomaki, Wukoki and Yumtheska soils are loamy-skeletal. Showlow soils are very deep.

DRAINAGE AND PERMEABILITY: Well drained; medium runoff; slow permeability.

USE AND VEGETATION: Used mainly for livestock grazing. Present vegetation is Utah juniper, pinyon pine, sideoats grama, and muttongrass.

DISTRIBUTION AND EXTENT: Northern Arizona. This series is of limited extent. MLRA is 35 and 38.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona

SERIES ESTABLISHED: Mohave County, Arizona; Soil survey of Mohave County Area, Arizona, Northeastern Part, and Part of Coconino County; 1992.

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

Mollic epipedon - the zone from 0 to 7 inches (A, Bt1 horizons) Munsell color within limits after mixing

Argillic horizon - the zone from 1 to 19 inches (Btk1, Btk2, Btk3 horizons)

Lithic contact - the boundary at 19 inches (2R horizon)

Classified according to Soil Taxonomy, Second Edition, 1999; Keys to Soil Taxonomy, Eleventh Edition, 2010

Revised for the correlation of AZ675, 5/2009, WWJ

Revised for the correlation of Graham County, AZ, Southwestern Part; March, 2011, WWJ

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National Cooperative Soil Survey
U.S.A.