LOCATION TRESANO            WY+CO
Established Series
Rev. JRS/CJF
10/2007

TRESANO SERIES


The Tresano series is a member of the fine-loamy, mixed, frigid family of Typic Haplargids. Typically, Tresano soils have grayish brown friable slightly alkaline sandy loam A1 horizons, brown slightly alkaline sandy clay loam B2t horizons, and grayish brown sandy clay loam B3ca and Cca horizons.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Typic Haplargids

TYPICAL PEDON: Tresano sandy loam rangeland. (Colors are for air dry soil unless otherwise noted.)

A--0 to 3 inches; grayish brown (10YR 5/2) sandy loam, dark grayish brown (10YR 4/2) moist; moderate fine granular structure; soft, very friable, slightly sticky, slightly plastic many fine and fine roots; slightly alkaline (pH 7.4); clear smooth boundary (2 to 4 inches thick).

AB--3 to 7 inches; grayish brown (10YR 5/2) sandy loam, dark grayish brown (10YR 4/2) moist; strong course granular structure; soft, very friable, slightly sticky, slightly plastic; many very fine, fine, and medium roots; slightly alkaline (pH 7.4); clear smooth boundary (2 to 5 inches thick).

Bt1--7 to 12 inches; brown (7.5YR 5/2) sandy clay loam, brown (7.5YR 4/2) moist; moderate medium prismatic that parts to moderate medium angular blocky structure; hard, firm, sticky, plastic; few fine and medium roots; thin nearly continuous waxy coatings on faces of peds; slightly alkaline (pH 7.6); abrupt smooth boundary (4 to 6 inches thick).

Btz--12 to 17 inches; brown (7.5YR 5/2) sandy clay loam, brown (7.5YR 4/2) moist; moderate medium angular blocky structure; hard, firm, sticky, plastic; few fine roots; thin nearly continuous waxy coatings on faces of peds; slightly alkaline (pH 7.6); clear smooth boundary ( 4 to 6 inches thick).

Bk1--17 to 24 inches; grayish brown (10YR 5/2) sandy clay loam, dark grayish brown (10YR 4/2) moist; weak medium angular blocky structure; slightly hard, friable, sticky, plastic; thin patchy waxy coatings on some faces of peds; calcareous; few fine and medium seams and soft masses of calcium carbonate; moderately alkaline (pH 8.4); gradual wavy boundary (5 to 8 inches thick).

Bk2--24 to 60 inches; grayish brown (10YR 5/2) sandy clay loam, dark grayish brown (10YR 4/2) moist; massive; slightly hard, friable, sticky, plastic; strongly calcareous; few fine and medium seams and soft masses of calcium carbonate; strongly alkaline (pH 8.6).

TYPE LOCATION: Sublette County, Wyoming; about 17 miles east of Marbleton; NE1/4, SW1/4, Sec. 24., T30N, R109W.

RANGE IN CHARACTERISTICS: The mean annual soil temperature is 36 to 47F. The mean summer soil temperature is 59 to 62 F. Dept to continuous horizons of secondary calcium carbonate is 12 to 28 inches. Calcium carbonate equivalent is less that 15 percent. The depth to the base of the argillic horizon is 12 to 28 inches. Very fine gravel ranges from 0 to 15 percent throughout.

The A1 horizon has hue of 2.5Y or 10YR; value of 5 or 6 dry, 4 or 5 moist; and chroma of 2 through 4 dry and moist. It is sandy loam, fine sandy loam, or very fine sandy loam. It is neutral or slightly alkaline.

The Bt has hue of 10YR or 7.5YR: value of 5 or 6 dry, 4 or 5 moist; and chroma of 2 through 4 dry and moist. It is loam sandy clay loam or clay loam averaging between 20 and 35 percent clay and less that 35 percent fine sand or coarser. It is neutral to moderately alkaline.

The Bk1 horizon has hue of 2.5Y through 7.5YR. Value 5 through 7 dry 4 to 0 moist chroma 2 to 6. It is sandy clay loam averaging between 18 and 28 percent clay. It is moderately alkaline or strongly alkaline.

The Bk2 horizon has hue of 2.5Y through 7.5YR. It is sandy loam or sandy clay loam. It is moderately alkaline or strongly alkaline.

COMPETING SERIES: These are the tentative Acacio and tentative Gini series. The Acacio soils have continuous horizons of secondary gypsum. The Gini soils (Idaho, please differentiate.)

GEOGRAPHIC SETTING: Tresano soils are on gently or moderately sloping alluvial plateaus fans. Slopes are 0 to 12 percent. They formed in mixed alluvial calcareous sediments & eolian. Mean annual temperature is 34 to 45F. Precipitation is 6 to 11 inches. Elevation is 6,000 to 7,000 feet. The frost-free is 75 to 110 days, but frost may occur in any month.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the tentative Debone soils. The Debone soils have natric horizons.

DRAINAGE AND PERMEABILITY: Well drained: low runoff; moderate permeability.

USE AND VEGETATION: Used for rangeland and wildlife habitat. Vegetation is big sagebrush, thickspike wheatgrass, Indian ricegrass, and needleandthread.

DISTRIBUTION AND EXTENT: Southwestern Wyoming and northwestern Colorado. The series is inextensive.

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

SERIES ESTABLISHED: Moffat County Area, Colorado, 1990. Proposed in Sublette County, Wyoming; 1973. The name is a coined name.


National Cooperative Soil Survey
U.S.A.