LOCATION HANGMANS                MT

Established Series
REV. KTS-GFB-RJS
01/2012

HANGMANS SERIES

The Hangmans series consists of very shallow, somewhat excessively drained soils that formed in colluvium and/or residuum derived from hard sedimentary rock. These soils occur on hills, ridges and structural benches. Slopes are 8 to 45 percent. Mean annual precipitation is about 300 mm, and the mean annual air temperature is about 6 degrees C.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, calcareous, frigid Aridic Lithic Ustorthents

TYPICAL PEDON: Hangmans very channery sandy loam, in rangeland, at an elevation of 1830 meters (colors are for dry soil unless otherwise noted).

A--0 to 8 cm; grayish brown (2.5Y 5/2) very channery sandy loam, olive brown (2.5Y 4/3) moist; weak fine and medium subangular blocky structure parting to weak fine granular; soft, very friable, slightly sticky and nonplastic; common very fine and few fine roots; common very fine and fine interstitial and tubular pores; 40 percent channers, 5 percent flagstones; slightly alkaline (pH 7.6); clear smooth boundary. (5 to 10 cm thick)

C--8 to 16 cm; light yellowish brown (2.5Y 6/3) extremely channery sandy loam, olive brown (2.5Y 4/3) moist; massive; soft, very friable, slightly sticky and nonplastic; common very fine and few fine roots; common very fine and fine interstitial and tubular pores; 60 percent channers, 10 percent flagstones; strongly effervescent; finely disseminated calcium carbonate; moderately alkaline (pH 8.0); clear smooth boundary. (5 to 15 cm thick)

R--16 to 152 cm; hard sandstone bedrock.

TYPE LOCATION: Beaverhead County, Montana; located about 180 meters north and 425 meters east of the SW corner of sec. 14, T. 8 S., R 11 W. Bannack topographic quadrangle. UTM 12T, 349030e, 4999421n. NAD 83

RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 5 to 8 degrees C.
Depth to lithic contact - less than 25 cm

A horizon
Hue: 10YR or 2.5Y; dry or moist
Value: 5 to 7 dry; 4 to 6 moist
Chroma: 2 or 3; dry or moist
Texture: loam or sandy loam
Clay content: 12 to 22 percent
Rock fragments: 35 to 60 percent--20 to 45 percent channers or gravel, 5 to 25 percent flagstones or cobbles
Calcium carbonate equivalent: 0 to 3 percent.
Reaction: pH 6.8 to 7.8

C horizons
Hue: 10YR or 2.5Y; dry or moist
Value: 5 to 7 dry; 4 or 6 moist
Chroma: 2 to 4; dry or moist
Texture: loam or sandy loam
Clay content: 10 to 18 percent
Rock Fragments: 40 to 80 percent--30 to 65 percent channers or gravel, 10 to 30 percent flagstones or cobbles
Calcium carbonate equivalent: 5 to 15 percent.
Reaction: pH 7.9 to 8.4

COMPETING SERIES:
Bloodstone (WY) - have hues of 2.5YR or 5YR
Gompers (UT) - have a calcium carbonate equivalent of 15 to 30 percent throughout the profile

GEOGRAPHIC SETTING:
Landform - hills, ridges and structural benches
Elevation - 1675 to 1980 meters
Slope - 8 to 45 percent
Parent material - colluvium and/or residuum from hard sedimentary rock
Climate - long, cold winters; moist springs; warm summers
Mean annual precipitation - 250 to 350 mm
Mean annual air temperature - 4 to 7 degrees C.
Frost-free period - 70 to 90 days

GEOGRAPHICALLY ASSOCIATED SOILS: None listed.

DRAINAGE AND PERMEABILITY: Somewhat excessively drained; moderately rapid permeability.

USE AND VEGETATION: Hangmans soils are used mainly for rangeland and wildlife habitat. Potential native vegetation is mainly sagebrush, rabbitbrush, bluebunch wheatgrass, Indian ricegrass, and miscellaneous forbs.

DISTRIBUTION AND EXTENT: Hangmans soils are of small extent in southwestern Montana. MLRA - 43B.

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

SERIES ESTABLISHED: Horse Prairie-South Valley Area - Part of Beaverhead County, Montana, 2011; proposed in Beaverhead County, Montana, 2011.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - from 0 to 8 cm (A horizon)
Lithic contact - at 16 cm (R horizon)
Particle-size control section - from 0 to 16 cm (A and C horizons)

Hangmans soils have a frigid temperature regime and an ustic moisture regime bordering on aridic.

Taxonomic version: Eleventh Edition, 2010

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National Cooperative Soil Survey
U.S.A.