LOCATION WOODHURST               MT

Established Series
Rev. CAM-JJU-EMM
04/2014

WOODHURST SERIES


The Woodhurst series consists of moderately deep, well drained soils formed in colluvium over residuum derived from nonacid igneous rocks. These soils are on hills and mountains. Slopes are 8 to 40 percent. Mean annual precipitation is about 22 inches, and mean annual air temperature is about 40 degrees F.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive Pachic Argicryolls

TYPICAL PEDON: Woodhurst stony loam, in native grass (colors are for dry soil unless otherwise noted).

A--0 to 12 inches; very dark grayish brown (10YR 3/2) stony loam, very dark brown (10YR 2/2) moist; weak fine granular structure; soft, very friable, slightly sticky and slightly plastic; many very fine roots; many fine interstitial pores; 20 percent stones; slightly alkaline (pH 7.6); clear boundary. (8 to 19 inches thick)

Bt1--12 to 20 inches; dark grayish brown (10YR 4/2) very stony clay loam, very dark grayish brown (10YR 3/2) moist; moderate fine blocky structure that parts to very fine granular;; soft, friable, moderately sticky and moderately plastic; many very fine roots; many fine tubular pores; continuous distinct clay films on vertical faces and patchy clay films on horizontal faces with organically stained glossy films on weathered rock fragments; 50 percent rock fragments and weathered igneous rock fragments that crush easily in the hand; slightly alkaline (pH 7.8); clear boundary. (5 to 15 inches thick)

Bt2--20 to 26 inches; brown (10YR 4/3) extremely stony clay loam, dark brown (10YR 3/3) moist; moderate fine and medium blocky structure; slightly hard, friable, moderately sticky and moderately plastic; few very fine roots; distinct continuous clay films on all faces of peds; moderately alkaline (pH 8.3); 80 percent rock fragments; clear wavy boundary. (2 to 10 inches thick)

R--26 inches; light colored hard quartz monzonite porphyry rock in situ. Weathered rock has organic stainings which give rise to a darker colored appearance.

TYPE LOCATION: Judith Basin County, Montana; Little Belt Mountains; 1,500 feet north and 450 feet east of center of sec. 26, T. 14N, R. 11E.

RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 44 to 47 degrees F.
Average summer soil temperature - 55 to 59 degrees F.
Depth to lithic contact - 20 to 40 inches

A horizon
Hue: 2.5Y, 10YR or 7.5YR; dry or moist
Value: 3 or 4; dry
Chroma: 1 or 2; dry or moist
Texture: loam or sandy loam
Clay content: 13 to 27 percent
Rock fragments: 15 to 60 percent--0 to 25 percent gravel, 0 to 35 percent cobbles and stones
Reaction: pH 6.4 to 7.8

AB horizon present in some pedons.

Bt1 horizon
Hue: 2.5Y, 10YR or 7.5YR; dry or moist
Value: 4 or 5 dry; 3 or 4 moist
Chroma: 2 or 4; dry or moist
Texture: clay loam or sandy clay loam
Clay content: 22 to 35 percent
Rock fragments: 40 to 85 percent--15 to 35 percent gravel, 5 to 55 percent cobbles and stones
Reaction: pH 6.4 to 8.4

Bt2 horizon
Hue: 2.5Y, 10YR or 7.5YR; dry or moist
Value: 4 or 5 dry; 3 or 4 moist
Chroma: 2 to 4; dry or moist
Texture: loam, clay loam or sandy clay loam
Clay content: 20 to 35 percent
Rock fragments: 50 to 85 percent--20 to 60 percent gravel, 5 to 55 percent cobbles and stones
Reaction: pH 7.0 to 8.4

COMPETING SERIES:
Angelwhine (CA) - are very deep
Aspetill (CA) - are very deep
Badwater (WY) - are very deep
Bickmore (UT) - have secondary calcium carbonate accumulation
Bigcoulee (MT) - are very deep
Blackbear (MT) - have an udic moisture regime
Bluebell (NV) - are slightly or moderately acid in the argillic horizon
Booneville (ID) - are very deep
Buena vista (CO) - have secondary calcium carbonate accumulation
Dab (NV) - are very deep
Dailybasin (MT) - are very deep
Delhew (NV) - are very deep
Hawkinspeak (CA) - have a xeric moisture regime
Igor (WY) - are very deep
Keman (ID) - are very deep
Littlemud (NV) - have a xeric moisture regime
Lostcannon (CA) - are very deep
Monibasin (CA) - are very deep
Panin (NV) - have a xeric moisture regime
Parkalley (ID) - are very deep
Parkay (UT) - are very deep
Rangertaft (NV) - have a xeric moisture regime
Redbird (SD) - are very deep
Rutherford (ID) - have a xeric moisture regime
Sweetmount (CA) - are deep to a paralithic contact

GEOGRAPHIC SETTING:
Landform - hills and mountains
Elevation - 5,000 to 9,000 feet
Slope - 8 to 40 percent
Parent material - colluvium over residuum derived from nonacid igneous rocks
Mean annual precipitation - 20 to 24 inches
Mean annual air temperature - 36 to 45 degrees F.
Mean summer air temperature - 54 to 60 degrees F.
Frost-free period - 30 to 60 days

GEOGRAPHICALLY ASSOCIATED SOILS: None listed.

DRAINAGE AND PERMEABILITY: Well-drained; moderate permeability.

USE AND VEGETATION: Used as rangeland. Vegetation is bluebunch wheatgrass, Idaho fescue, rough rescue, needle-and-thread grass, sedges, balsamroot, fringed sagewort, lupine and silver sagebrush.

DISTRIBUTION AND EXTENT: Woodhurst soils are moderately extensive in central and southwestern Montana. MLRA 43B

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

SERIES ESTABLISHED: Judith Basin County, Montana, 1963.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - from 0 to 26 inches (A, Bt1, Bt2 horizons)
Argillic horizon - from 12 to 26 inches Bt1, Bt2 horizons)
Particle-size control section - from 12 to 26 inches (Bt1, Bt2 horizons)
Lithic contact - at 26 inches (R horizon)

Woodhurst soils have a cryic temperature regime and an ustic moisture regime.


National Cooperative Soil Survey
U.S.A.