LOCATION SOWARD             UT
Established Series
Rev: RHF/SSP
7/98

SOWARD SERIES


The Soward series consists of very deep, well drained soils that formed in alluvium derived from sedimentary rocks. These soils are in drainageways. Slopes are 3 to 15 percent. Mean annual precipitation is about 18 inches and the mean annual temperature is 42 degrees F.

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, frigid Cumulic Haplustolls

TYPICAL PEDON: Soward sandy loam on 4 percent south facing slopes under rangeland at an elevation of 7,200 feet. (Colors are for air-dry soil unless otherwise stated).

A1--0 to 3 inches; grayish brown (10YR 5/2) sandy loam, very dark grayish brown (10YR 3/2) moist; weak medium subangular blocky structure; soft, friable, slightly sticky and nonplastic; many fine and very fine roots; few fine tubular pores; very slightly effervescent, (2 percent calcium carbonate equivalent), carbonates are disseminated; moderately alkaline (pH 8.2); clear smooth boundary. (3 to 8 inches thick)

A2--3 to 11 inches; grayish brown (10YR 5/2) sandy loam, very dark grayish brown (10YR 3/2) moist; moderate medium subangular blocky structure; soft, friable, slightly sticky and nonplastic; many very fine, fine and few medium roots; few fine tubular pores; very slightly effervescent (3 percent calcium carbonate equivalent), carbonates are disseminated; moderately alkaline (pH 8.2); abrupt smooth boundary. (0 to 8 inches thick)

A3--11 to 17 inches; grayish brown (10YR 5/2) sandy loam, very dark grayish brown (10YR 3/2) moist; moderate medium subangular blocky structure; soft, friable, slightly sticky and nonplastic; many very fine, fine and common medium roots; few medium and common fine tubular pores; 5 percent gravel; slightly effervescent, (7 percent calcium carbonate equivalent), carbonates are disseminated; moderately alkaline (pH 8.4); clear smooth boundary. (6 to 15 inches thick)

A4--17 to 34 inches; grayish brown (10YR 5/2) sandy loam, very dark grayish brown (10YR 3/2) moist; moderate medium subangular blocky structure parting to weak fine subangular blocky; soft, friable, slightly sticky and nonplastic; many very fine, fine common medium and few coarse roots; common medium and fine tubular pores; 10 percent gravel; slightly effervescent, (5 percent calcium carbonate equivalent), carbonates are disseminated; moderately alkaline (pH 8.4); clear wavy boundary. (8 to 28 inches thick)

Bw1--34 to 49 inches; grayish brown (10YR 5/2) sandy loam, dark grayish brown (10YR 4/2) moist; weak medium subangular blocky structure; soft, friable, slightly sticky and nonplastic; common very fine, fine and few medium and coarse roots; common medium fine and few coarse tubular pores; 10 percent gravel; slightly effervescent, (7 percent calcium carbonate equivalent), carbonates are disseminated; moderately alkaline (pH 8.4); clear smooth boundary. (8 to 19 inches thick)

Bw2--49 to 60 inches; dark grayish brown (10YR 4/2) sandy loam, very dark grayish brown (10YR 3/2) moist; moderate medium subangular blocky structure parting to weak fine subangular blocky; soft, friable, slightly sticky and slightly plastic; common very fine and fine roots; common very fine and fine tubular pores; 5 percent gravel; slightly effervescent, (5 percent calcium carbonate equivalent), carbonates are disseminated; moderately alkaline (pH 8.4).

TYPE LOCATION: Uintah County, Utah; San Arroyo Ridge, Utah quadrangle; 41 miles south of Bonanza, Utah; 400 feet east and 1,100 feet south of northwest corner of sec. 22, T. 15 S., R. 24 E., SLBM; 39 degrees, 29 minutes, 59 seconds north latitude and 109 degrees, 13 minutes, 27 seconds west longitude; NAD 27.

RANGE IN CHARACTERISTICS:

Soil moisture: The soil moisture control section is affected by precipitation that falls evenly throughout the year, with a slight increase in late summer and fall. The moisture regime is typic ustic.
Mean annual soil temperature: 42 to 45 degrees F.
Mean summer soil temperature: 62 to 66 degrees F.
Thickness of the mollic epipedon: 16 to 60 inches

Particle size control section: 5 to 18 percent clay and 0 to 15 percent subrounded sandstone gravel and cobbles with individual horizons ranging to 35 percent

A horizon:
Values: 3 to 5 dry, 2 or 3 moist
Chroma: 2 or 3 dry, 1 to 3 moist
Texture: sandy loam or loam with clay content ranging from 10 to 18 percent, and content of subrounded sandstone gravel and cobbles ranging from 0 to 15 percent
Calcium carbonate equivalent: 0 to 5 percent

Bw horizon:
Values: 3 to 5 dry
Chroma: 2 or 3
Texture: sandy loam, fine sandy loam or loam with clay content ranging from 5 to 18 percent, and content of subrounded sandstone gravel and cobbles ranging from 0 to 15 percent
Calcium carbonate equivalent: 3 to 10 percent

COMPETING SERIES: There are no current competitors.

GEOGRAPHIC SETTING:

Parent material: alluvium derived from sedimentary rocks of the Green River Formation
Landform: drainageways
Slopes: 3 to 15 percent
Elevation: 6,600 to 8,400 feet
Mean annual precipitation: 16 to 22 inches
Mean annual air temperature: 40 to 43 degrees F.
Frost-free period: 70 to 90 days

GEOGRAPHICALLY ASSOCIATED SOILS: All these soils are on dissected plateau hillslopes. These are the Pathead, Saddlehorse and the Tosca soils. Pathead soils do not have a mollic epipedon and they have a lithic contact at depths of 20 to 40 inches. Saddlehorse soils have a calcic horizon and have a paralithic contact at depths of 20 to 40 inches. Tosca soils have a calcic horizon and have a lithic contact at depths of 40 to 60 inches.

DRAINAGE AND PERMEABILITY: Well drained; very low or low runoff; moderately rapid permeability.

USE AND VEGETATION: These soils are used for rangeland, wildlife habitat and recreation. Potential native vegetation is basin wildrye, mountain big sagebrush, mountain brome and Columbia needlegrass. These soils have been correlated to the Mountain Loamy Bottom (Basin Wildrye) - 048AY410UT range site in Utah.

DISTRIBUTION AND EXTENT: Northeast Utah; LRR E; MLRA 48A. The series is of small extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana

SERIES ESTABLISHED: Uintah County, Uintah Area Soil Survey, Utah, 1998. The name comes from a geographic feature within the survey area.

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

Particle-size control section: The zone from 10 to 40 inches. (A2, A3, A4, and Bw1 horizons)
Mollic epipedon: The zone from the surface of the soil to a depth of 34 inches. (A1, A2, A3, and A4 horizons)
Cambic horizon: The zone of structural development from 34 to 60 inches. (Bw1 and Bw2 horizons).

The classification was changed from Cumulic Haploboroll to frigid Cumulic Haplustoll July 1998.

Taxonomic version: Eighth Edition, 1998.

The CEC activity class was inferred from laboratory data from similar soils in the Uintah Area Soil Survey.


National Cooperative Soil Survey
U.S.A.