LOCATION SKOS               UT
Established Series
Rev: MEO/DTH
10/2008

SKOS SERIES


The Skos series consists of very shallow to shallow, well drained, moderately permeable soils that formed in residuum and colluvium from interbedded sandstone, siltstone and shale. Skos soils occur on structural benches, ridges, and hillsides on structural benches and have slopes of 4 to 60 percent. The average annual precipitation is about 12 inches and the mean annual temperature is about 50 degrees F.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, calcareous, mesic Lithic Ustic Torriorthents

TYPICAL PEDON: Skos channery loam, rangeland. (Colors are for air-dry soil unless otherwise stated.)

A--0 to 1 inch; reddish brown (2.5YR 4/4) channery loam, red (2.5YR 4/6) moist; weak fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; few fine pores; 25 percent channers, 5 percent gravel on surface and in matrix; slightly calcareous; carbonates are disseminated; moderately alkaline (pH 8.0); abrupt smooth boundary. (0 to 4 inches thick)

C--1 to 6 inches; reddish brown (2.5YR 4/4) very channery sandy clay loam, reddish brown (2.5YR 4/4) moist; massive, hard, firm, sticky and plastic; few very fine and fine roots; few fine pores; 40 percent channers, 10 percent gravel; moderately calcareous; carbonates are disseminated; moderately alkaline (pH 8.0); clear wavy boundary. (3 to 17 inches thick)

R--6 inches; sandstone.

TYPE LOCATION: San Juan County, Utah, about 13 miles southwest of the intersection of state highways 95 and 263; 1,000 feet north and 1,000 feet west of the southeast corner of sec. 11, T. 38 S., R. 15 E.

RANGE IN CHARACTERISTICS:

Soil moisture- usually dry when the soil temperature exceeds 41 degrees F., but they usually are moist in some part of the moisture control section for at least 45 consecutive days. The moist period occurs during the months of July, August, and September. Ustic aridic moisture regime.

Mean annual soil temperature: 47 to 56 degrees F.

Depth to bedrock: 4 to 20 inches.

Particle-size control section-

Clay content: 18 to 35 percent

Rock fragment: 35 to 60 percent

Hues: 2.5YR, 5YR

A horizon
Value: 4 or 5 dry, 3 or 4 moist
Chroma: 4 to 6 dry, or moist
Reaction: slightly alkaline or moderately alkaline
Effervescence: slightly calcareous to strongly calcareous

C horizon
Value: 4 to 6 dry, 3 to 5 moist
Chroma: 4 to 6 dry, or moist
Textures: sandy clay loam, clay loam, silt loam, silty clay loam, loam.

COMPETING SERIES: These are the Andanada (NM), Daklos, (UT), Ednagrey (), Hillburn (UT), Meriwhitica (AZ), Nonip (UT), Redsun (WY), Reef (UT), Sunup (AZ), Teesto (AZ) and Windcomb (UT) series. Ednagrey, Meriwhitica, Redsun, Reef, and Windcomb soils have less than 18 percent clay. Andanada, Daklos, Meriwhitica, Nonip, and Teesto soils have hues of 7.5YR or yellower. Sunup, Redsun, and Windcomb soils are moist in the soil moisture control section during May and June. Hillburn soils are inactive.

GEOGRAPHIC SETTING: Skos soils are on structural benches, ridges, and hillsides on structural benches. Elevations range from 4,400 to 8,000 feet. Above elevations of 7,000 feet, Skos soils occur on south facing mountainsides. Mean annual temperature is 45 to 54 degrees F., and the average annual precipitation is 9 to 14 inches. The freeze-free period is 100 to 160 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Sazi, Mivida, and Rizno soils. Sazi and Mivida soils are greater than 20 inches deep to bedrock.
Rizno soils have less than 35 percent rock fragments in the particle-size control section.

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

USE AND VEGETATION: Used as rangeland and wildlife habitat. Potential vegetation is Utah juniper, pinyon, blackbrush, and Mormon-tea.

DISTRIBUTION AND EXTENT: Southeast Utah. The series is of moderate extent. MLRA 35.

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

SERIES ESTABLISHED: San Juan County, Central Part, Utah, 1985.

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

Ochric epipedon - the zone from the surface of the soils to 1 inch (A horizon)

Lithic feature - Sandstone at 6 inches (R horizon)

Competing series section updated June 26, 2008, CEM


National Cooperative Soil Survey
U.S.A.