LOCATION RUSON                   NM

Established Series
Rev. JER/RJA/SJJ
08/2016

RUSON SERIES

The Ruson series consists of very deep, well drained soils that formed in alluvium derived dominantly from shale. Ruson soils are on valley floors with slopes of 0 to 4 percent. The mean annual precipitation is about 16 inches, and the mean annual temperature is about 46 degrees F.

TAXONOMIC CLASS: Fine, mixed, superactive, calcareous, mesic Typic Ustorthents

TYPICAL PEDON: Ruson silt loam--rangeland. (Colors are for dry soil unless otherwise noted.)

A--0 to 2 inches; light brownish gray (2.5Y 6/2) silt loam, grayish brown (2.5Y 5/2) moist; weak fine granular structure; soft, very friable, sticky and plastic; few very fine and fine roots; few fine interstitial pores; strongly effervescent; moderately alkaline (pH 8.4); clear smooth boundary. (1 to 4 inches thick)

C1--2 to 19 inches; light brownish gray (2.5Y 6/2) silty clay loam, grayish brown (2.5Y 5/2) moist; massive; hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; few fine interstitial pores; strongly effervescent; moderately alkaline (pH 8.4); clear smooth boundary. (3 to 58 inches thick)

C2--19 to 65 inches; grayish brown (10YR 5/2) clay, dark grayish brown (10YR 4/2) moist; massive; hard, firm, sticky and plastic; few very fine and fine roots; few fine interstitial pores; strongly effervescent; moderately alkaline (pH 8.2).

TYPE LOCATION: Rio Arriba County, New Mexico; east of Berryman Ranch Headquarters; 2,700 feet west and 1,980 feet north from the SE corner of sec. 34, T. 26 N., R. 4 E; 106 degrees, 30 minutes, 02 seconds west longitude; 36 degrees, 26 minutes, 29 seconds north latitude.

RANGE IN CHARACTERISTICS:

Soil Moisture: Intermittently moist in some part of the soil moisture control section December through April and July through September. The soil is driest during May and June.

Soil Temperature: 47 to 51 degrees F.

Rock fragments: 0 to 15 percent pebbles.

A horizon: Hue - 10YR or 2.5Y. Value: 5 or 6 dry, 4 or 5 moist. Chroma: 2 through 4.
Texture: silt loam or clay loam

C horizon: Hue - 10YR or 2.5Y. Value: 5 through 7 dry, 4 or 5 moist. Chroma: 2 through 6.
Texture: silty clay, silty clay loam, clay loam or clay. Clay Content: 35 to 50 percent.

COMPETING SERIES: There are no competing series in the same family. The similar Berryman soils have a cambic horizon and are carbonatic.

GEOGRAPHIC SETTING: Ruson soils are on valley floors with slopes of 0 to 4 percent. Elevations range from 7,100 to 7,600 feet. The soils formed in alluvium derived dominantly from shale. The mean annual precipitation is 14 to 17 inches. The mean annual temperature is 45 to 48 degrees F., and the frost-free season is about 100 to 120 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Berryman and Teromote soils. Teromote soils have cambic horizons.

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

USE AND VEGETATION: Ruson soils are used for grazing livestock. The present vegetation is western wheat and big sagebrush.

DISTRIBUTION AND EXTENT: Northern New Mexico. Series is of small extent.

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

SERIES ESTABLISHED: Rio Arriba County, New Mexico, 1989.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric Epipedon - 0 to 2 inches (A horizon)
Entisol feature - lack of diagnostic horizons.

The soil moisture regime of "Typic Ustic" should probably be re-evaluated. Similar soils in southern Colorado with 14 to 17 inches of ppt are classified as "Aridic Ustic".

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National Cooperative Soil Survey
U.S.A.