LOCATION MUG                     ID

Established Series
Rev. DL/MJ/CLM
09/2019

MUG SERIES

The Mug series consists of soils that are well drained and moderately deep soils that formed in colluvium and residuum from welded tuff. They are on terraces, basalt plains, and foothills. Permeability is very slow. Slopes range from 1 to 12 percent. The average annual precipitation is about 330 mm, and the average annual temperature is about 8.3 degrees C.

TAXONOMIC CLASS: Clayey-skeletal, smectitic, frigid Ultic Palexerolls

TYPICAL PEDON: Mug very cobbly loam - on a slope of 4 percent under rangeland vegetation at 1,710 meters elevation. When described on November 11, 1981, the soil was dry throughout. (Colors are for dry soil unless otherwise noted.)

A--0 to 13 cm; grayish brown (10YR 5/2) very cobbly loam, very dark grayish brown (10YR 3/2) moist; weak medium platy structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine and fine roots; many very fine tubular pores; 20 percent cobbles, 20 percent gravel; slightly acid (pH 6.4); abrupt smooth boundary. (10 to 18 cm thick)

Bt--13 to 36 cm; grayish brown (10YR 5/2) extremely cobbly clay loam, very dark grayish brown (10YR 3/2) moist; strong fine angular blocky structure; hard, firm, moderately sticky and moderately plastic; common very fine and fine roots; many very fine tubular pores; common distinct clay films on faces of peds and in pores; 30 percent cobbles, 40 percent gravel; slightly acid (pH 6.3); abrupt smooth boundary. (0 to 23 cm thick)

2Bt--36 to 64 cm; brown (7.5YR 5/4) gravelly clay, dark brown (7.5YR 4/4) moist; strong coarse prismatic structure; extremely hard, very firm, very sticky and very plastic; few very fine and fine roots; few very fine tubular pores; many prominent clay films on faces of peds and in pores; 20 percent gravel, 5 percent cobbles; neutral (pH 6.7); abrupt smooth boundary. (23 to 50 cm thick)

2R--64 cm; gray (10YR 6/1) welded tuff, dark gray (10YR 4/1) moist; thin inconsistent calcium carbonate-silica coating on the rock surface.

TYPE LOCATION: Twin Falls County, Idaho about 21 miles southwest of Rogerson, Idaho; about 1,040 feet north and 360 feet east of the southwest corner of section 6, T. 15 S., R. 13 E.; USGS Cedar Creek Reservoir 7.5 minute topographic quadrangle; latitude 42 degrees 08 minutes 46 seconds N and longitude 114 degrees 59 minutes 20 seconds W; WGS84 Decimal Degrees 42.1461111 latitude, -114.9888889 longitude.

RANGE IN CHARACTERISTICS:

Depth to the welded tuff - 50 to 100 cm.
Mollic epipedon - 18 to 38 cm.
Average clay percent in the control section - 35 to 60
Base saturation upper 50 cm of argillic horizon - 65 to 75 percent.
Rock fragments in the control section - 40 to 80 percent
Average annual soil temperature - 6.7 to 7.8 degrees F.
Moisture, soil - dry for more than 90 consecutive days during the summer. Typic xeric moisture regime.

A horizon
Value - 4 or 5 dry, 2 or 3 moist
Chroma - 1 through 3 dry or moist

Bt1 horizon
Chroma - 2 or 3 dry or moist
Texture - GRV-C, GRX-CL
Gravel - 35 to 50 percent
Cobbles - 5 to 30 percent

2Bt2 or Btb horizons
Hue - 10YR or 7.5YR
Value - 4 to 6 dry
Chroma - 2 through 4 dry or moist
Texture - GR-C, CB-C, GBX-SICL, CBX-SIC, and CBV-SIC
Gravel - 5 to 25 percent
Cobbles - 5 to 60 percent
Stones - 0 to 20 percent
Reaction - moderately acid to neutral

COMPETING SERIES: This is the Boiler, Hudspeth, and the Player series. Boiler and Player soils are greater than 150 cm deep to bedrock. Hudspeth soils are usually moist and are dry between a depth of 10 and 30 cm for less than 90 consecutive days during the summer.

GEOGRAPHIC SETTING: Mug soils are on terraces basalt plains and foothills. The slope ranges from 1 to 12 percent. The soils formed in colluvium and residuum from welded tuff or basalt. Elevations are 1,525 to 1,925 meters. The average annual precipitation ranges from300 to 410 mm. The average annual temperature is 6.1 to 7.2 degrees C. The frost free season is 60 to 100 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Amboat, Arness, Brose, Eep, and Dehana soils. Amboat and Brose soils occur on summits. Amboat soils are deep. Brose soils are shallow, and are not skeletal. Arness soils occur on lower terraces, and have sandy clay loam or sandy clay argillic horizons. Dehana and Eep soils are deep, and occur on sideslopes or breaks.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained, medium runoff; very slow saturated hydraulic conductivity.

USE AND VEGETATION: Mug soils are used for rangeland. Native vegetation is bluebunch wheatgrass, Idaho fescue, and low sagebrush.

DISTRIBUTION AND EXTENT: Mug soils are of small extent in south central Idaho. MLRA 25, 11 and 43C.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California

SERIES ESTABLISHED: Twin Falls County, Idaho, 1992.

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

Mollic epipedon - 0 to 36 cm (A and Bt horizons).
Abrupt texture change - The boundary at 13 cm (upper Bt boundary). Argillic horizon - 13 to 64 cm (Bt and 2Bt horizons)

Ultic feature - BS less than 75 percent in some part of upper 50 cm.
Lithic contact - The boundary at 64 cm (R boundary).


Particle-size control section - 13 to 63 (Bt and part of the 2Bt horizons).

ADDITIONAL DATA: Clay percent by hydrometer: 0 to 13 cm - 20 percent; 13 to 36 cm - 36 percent; 36 to 64 cm - 58 percent.
Base saturation: 0 13 cm - 76 percent; 13 to 36 cm - 67 percent; 36 to 64 cm - 78 percent.

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National Cooperative Soil Survey
U.S.A.