LOCATION TOVAR              AZ
Established Series
Rev. DRT/RLB/PDC
08/2007

TOVAR SERIES


The Tovar series consists of moderately deep, well drained soils that formed in residuum, alluvium and colluvium from tuff, volcanic breccia and sandstone. Tovar soils are on hills, plateaus, structural benches and have slopes that range from 1 to 60 percent. The mean annual precipitation is about 15 inches and mean annual air temperature is about 51 degrees F.

TAXONOMIC CLASS: Fine, smectitic, mesic Vertic Paleustalfs

TYPICAL PEDON: Tovar fine sandy loam - grazable woodland. (Colors are for dry soil unless otherwise noted.)

A--0 to 3 inches; brown (7.5YR 5/4) fine sandy loam, reddish brown (5YR 4/3) moist; weak thick platy structure parting to moderate fine granular; soft, very friable, nonsticky and nonplastic; few fine and very fine roots; common fine and very fine vesicular pores; 10 percent channers; neutral (pH 7.0); clear smooth boundary. (2 to 5 inches thick)

Bw--3 to 8 inches; brown (7.5YR 4/4) flaggy fine sandy loam, dark reddish brown (5YR 3/4) moist; weak fine subangular blocky structure; hard, friable, slightly sticky and slightly plastic; common fine roots; common fine discontinuous irregular pores; 20 percent flagstones and 10 percent channers; neutral (pH 7.2); clear smooth boundary. (0 to 6 inches thick)

2Bt1--8 to 16 inches; dark reddish brown (5YR 3/4) flaggy clay, dark reddish brown (5YR 3/4) moist; strong medium and coarse prismatic structure; very hard, very firm, sticky and very plastic; common very fine roots; few very fine discontinuous irregular pores; 20 percent flagstones and 10 percent channers; continuous distinct clay films on faces of peds; slightly alkaline (pH 7.4); clear smooth boundary. (6 to 9 inches thick)

2Bt2--16 to 25 inches; reddish brown (5YR 4/4) flaggy clay, reddish brown (5YR 4/4) moist; strong medium subangular blocky structure; very hard, very firm, sticky and very plastic; common very fine roots; few very fine discontinuous irregular pores; 20 percent flagstones and 10 percent channers; continuous distinct clay films on faces of peds; slightly alkaline (pH 7.4); gradual smooth boundary. (8 to 10 inches thick)

2Bt3--25 to 35 inches; yellowish red (5YR 4/6) flaggy clay, reddish brown (5YR 4/4) moist; moderate fine and medium subangular blocky structure; very hard, very firm, sticky and plastic; few very fine roots; few very fine discontinuous irregular pores; 30 percent flagstones; many distinct clay films on faces of peds; slightly alkaline (pH 7.6); abrupt smooth boundary. (0 to 10 inches thick)

3R--35 inches; thin-bedded hard sandstone; few thin calcium carbonate coatings in fractures.

TYPE LOCATION: Coconino County, Arizona; about 10 miles north of Ashfork and 500 feet south of Santa Fe Railroad; 800 feet north and 600 feet west of the center of section 13, T. 23 N., R. 3 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 58 degrees F.

Depth to bedrock: 20 to 40 inches

Linear extensibility: 6.0 cm or more from the surface horizon to bedrock

Other features: Some pedon may or may not have lithologic discontinuities

Rock fragments: averages 5 to 35 percent gravel, channers, flagstones and stones. The control section rock fragments may ranges up to 75 percent in any horizon.

A horizon
Hue: 7.5YR, 5YR, 10YR
Value: 3 to 6 dry, 3 or 4 moist
Chroma: 3 to 6, dry or moist
Reaction: slightly acid to slightly alkaline

Bt horizon
Hue: 2.5YR, 5YR
Value: 3 to 6 dry, 3 or 4 moist
Chroma: 3 to 6, dry or moist
Texture: clay loam, clay (35 to 55 percent clay). 15 percent or more (absolute) clay increase at the upper boundary within a vertical distance of 1 inch
Reaction: neutral to moderately alkaline
Calcium carbonate: none to few as segregated filaments or soft masses

Bw horizon is absent in some pedons.

COMPETING SERIES: These are the Pinntank (AZ) and Theecan (AZ) series. Pinntank soils have a Typic ustic soil moisture regime. Theecan soils are very deep.

GEOGRAPHIC SETTING: The Tovar soils are on hills, plateaus, mesas and structural benches with slopes of 1 to 60 percent. Elevations are 4500 to 7000 feet. They formed in residuum, alluvium and colluvium from tuff, volcanic breccia, limestone and sandstone. The climate is semiarid with precipitation ranging from 14 to 18 inches occurring as summer thunderstorms and winter rain and snow. The mean annual air temperature is 45 to 57 degrees F. The average January temperature is about 35 degrees F., and the average July temperature is about 73 degrees F. Frost-free period is 120 to 180 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Luzena, Showlow and Thunderbird soils. These soils have mollic epipedons.

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

USE AND VEGETATION: Used for livestock grazing, fuelwood production and wildlife habitat. Vegetation is mainly oneseed juniper, blue grama, sideoats grama, sand dropseed, bottlebrush squirreltail, algerita, and broom snakeweed.

DISTRIBUTION AND EXTENT: North central Arizona. The series is moderately extensive. MLRA 35.

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

SERIES ESTABLISHED: Coconino County Area, Arizona, Central Part; 1980.

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

Ochric epipedon - The zone from 0 to 3 inches (A horizon)

Argillic horizon - The zone from 8 to 35 inches (2Bt1, 2Bt2, and 2Bt3 horizons)

Lithic contact - The boundary at 35 inches (3R horizon)

Vertic subgroup - Linear extensibility of 6.0 cm or more to bedrock

Classified according to Soil Taxonomy Second Edition, 1999; Keys to Soil Taxonomy Tenth Edition, 2006.

ADDITIONAL DATA: NSSL S77AZ-5-5


National Cooperative Soil Survey
U.S.A.