LOCATION TARGHEE                 ID+CO+MT

Established Series
Rev. LAR-JJU-RJS
06/2011

TARGHEE SERIES


The Targhee series consists of moderately deep, well drained soils that formed in slope alluvium, colluvium or slide deposits derived from rhyolitic tuff, gneiss, granite, or basalt rock sources. These soils are on mountain slopes and landslides. Slopes range from 1 to 60 percent. Mean annual precipitation is about 33 inches, and the mean annual air temperature is about 37 degrees F.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive Typic Haplocryepts

TYPICAL PEDON: Targhee loam - on a 2 percent nearly level west-facing slope in woodland. When described on June 12, 1979, the soil was moist below 15 inches (colors are for dry soil unless otherwise noted).

A--0 to 5 inches; pale brown (10YR 6/3) loam, dark brown (10YR 3/3) moist; strong fine granular structure; slightly hard, friable, nonsticky and nonplastic; many very fine and fine, and common medium roots; common very fine discontinuous random vesicular pores; moderately acid (pH 5.6); gradual smooth boundary. (4 to 7 inches thick)

Bw--5 to 14 inches; light gray (10YR 7/2) gravelly sandy loam, brown (10YR 4/3) moist; weak fine subangular blocky structure parting to moderate fine granular; soft, very friable, nonsticky and nonplastic; many very fine and fine, and common medium roots; common very fine discontinuous random vesicular pores; 25 percent gravel; slightly acid (pH 6.2); gradual wavy boundary. (5 to 15 inches thick)

C1--14 to 30 inches; white (10YR 8/1) very gravelly sandy loam, brown (10YR 5/3) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; many fine and common medium roots; few very fine oblique random vesicular pores; 35 percent gravel; moderately acid (pH 6.0); gradual wavy boundary. (3 to 20 inches thick)

2C2--30 to 36 inches; white (10YR 8/1) extremely cobbly sand, light brownish gray (10YR 6/2) moist; single grain; loose, nonsticky and nonplastic; 40 percent gravel and 50 percent cobbles; moderately acid (pH 6.0); abrupt wavy boundary. (3 to 20 inches thick)

2R--36 inches; rhyolitic tuff.

TYPE LOCATION: Fremont County, Idaho; about 1 mile east of Elk Creek Ranch; 800 feet south and 500 feet west of the northeast corner, sec. 23, T. 13N, R. 43E.

RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 38 to 41 degrees F.
Depth to lithic contact - 20 to 40 inches
Particle-size control section (weighted average) - 40 to 75 percent rock fragments

Note: An O horizon may be present.

A horizon
Value: 5 to 7 dry
Chroma: 2 to 4 moist
Rock fragments: 0 to 35 percent

Bw horizon
Hue: 7.5YR or 10YR; dry or moist
Value: 6 to 8 dry; 3 to 5 moist
Chroma: 2 to 4; dry or moist
Texture: loam or sandy loam
Clay content: 6 to 16 percent
Rock fragments: 25 to 65 percent

C1, 2C2 horizons
Value: 6 to 8 dry; 4 to 6 moist
Chroma: 1 to 4; dry
Texture: sandy loam, loamy sand or sand
Rock fragments: 25 to 95 percent

COMPETING SERIES:
Basaltlake (AK) - are very deep
Butchlake (AK) - are very deep
Cuberant (UT) - do not have a lithologic discontinuity
Enentah (CO) - are very deep
Garlet (MT) - are very deep
Gromes (NM) - are very deep
Holokukfamily (AK) - are very deep
Kegsprings (MT) - are very deep
Mountedith (MT) - are very deep
Soakpak (AK) - are very deep
Storm (CO) - are very deep
Telay (AK) - are very deep

GEOGRAPHIC SETTING:
Landform - mountain slopes and landslides
Elevation - 6,200 to 9,500 feet; 10,000 to 11,200 feet in Colorado
Slope - 1 to 60 percent
Parent material - slope alluvium, colluvium or slide deposits derived from rhyolitic tuff, gneiss, granite, or basalt rock sources
Mean annual precipitation - 25 to 35 inches
Mean annual air temperature - 36 to 39 degrees F.
Frost-free period - 30 to 60 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bootjack and Chickreek soils. Bootjack soils are on river terraces and outwash plains and have a silty clay loam surface horizon, are very deep and are poorly drained. Chickreek soils are on floodplains, have an ash layer immediately below the surface, are very deep and are poorly drained.

DRAINAGE AND PERMEABILITY: Well drained; medium or rapid runoff; permeability is moderately rapid in the upper part and very rapid in the lower part.

USE AND VEGETATION: Targhee soils are used principally as grazeable woodland, commercial woodland, and summer homes. Vegetation is mainly lodgepole pine and pine reedgrass.

DISTRIBUTION AND EXTENT: Targhee soils are of moderate extent in eastern Idaho, northwestern Colorado, and southwestern Montana. MLRAs - 13, 43B, 48A.

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

SERIES ESTABLISHED: Rio Blanco County (Flat Tops Area), Colorado, 1984.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - from 0 to 5 inches (A horizon)
Cambic horizon - from 5 to 14 inches (Bw horizon)
Lithic contact - at 36 inches (2R horizon)
Particle-size control section - from 10 to 36 inches (part of the Bw, C1, 2C2 horizons)

Targhee soils have a cryic temperature regime and an udic soil moisture regime.

Additional Information: The 3/2008 description reflects a change in classification from Loamy-skeletal, mixed, superactive Typic Eutrocryepts to Loamy-skeletal, mixed, superactive Typic Haplocryepts due to revision of the cryepts great groups and subgroups.


National Cooperative Soil Survey
U.S.A.