LOCATION WILHELM                 WY

Tentative Series
Rev. TAG-DMM-RJS
02/2011

WILHELM SERIES

The Wilhelm series consists of very deep, well drained soils that formed in alluvium or outwash derived from metamorphic and sedimentary rock. These soils are on fan remnants and outwash terraces. Slopes are 1 to 6 percent. Mean annual precipitation is about 432 mm, and mean annual air temperature is about 1.3 degrees C.

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

TYPICAL PEDON: Wilhelm gravelly loam, in rangeland (colors are for dry soil unless otherwise noted).

A--0 to 13 cm; dark brown (7.5YR 3/2) crushed, gravelly loam, very dark brown (7.5YR 2/2) crushed, moist; weak very fine granular structure; soft, very friable, slightly sticky, slightly plastic; many fine roots throughout; many fine vesicular pores; 25 percent gravel, 5 percent cobbles; neutral (pH 6.6); clear smooth boundary. (10 to 19 cm thick)

Bt--13 to 28 cm; dark brown (7.5YR 3/2) crushed, gravelly clay loam, very dark brown (7.5YR 2/2) crushed, moist; moderate fine subangular blocky structure; moderately hard, firm, moderately sticky, moderately plastic; many fine roots throughout; many fine tubular pores; few patchy faint clay films on all faces of peds; 25 percent gravel, 5 percent cobbles; neutral (pH 6.6); clear smooth boundary. (10 to 20 cm thick)

Btk1--28 to 43 cm; reddish brown (5YR 5/4) broken face, very gravelly clay loam, reddish brown (5YR 4/4) broken face, moist; moderate fine subangular blocky structure; moderately hard, firm, moderately sticky, moderately plastic; many fine roots throughout; many fine tubular pores; few patchy distinct clay films on all faces of peds; many fine prominent moderately cemented carbonate nodules on bottom of rock fragments; 5 percent paragravel, 35 percent gravel, 5 percent cobbles; slightly effervescent (3 percent calcium carbonate equivalent); neutral (pH 6.8); gradual wavy boundary.

Btk2--43 to 64 cm; reddish brown (5YR 5/4) broken face, very gravelly clay loam, reddish brown (5YR 4/4) broken face, moist; moderate medium subangular blocky structure; moderately hard, firm, moderately sticky, moderately plastic; common fine roots throughout; many fine tubular pores; few patchy faint clay films on all faces of peds; many fine prominent moderately cemented carbonate nodules on bottom of rock fragments and common fine distinct carbonate masses throughout; 5 percent paragravel, 40 percent gravel, 10 percent cobbles, 1 percent stones; strongly effervescent (6 percent calcium carbonate equivalent); slightly alkaline (pH 7.8); gradual wavy boundary. (combined thickness of Btk1 and Btk2 - 20 to 40 cm thick)

Bkk--64 to 94 cm; pinkish white (5YR 8/2) broken face, very gravelly loam, pink (5YR 7/3) broken face, moist; weak very fine subangular blocky structure; hard, very firm, moderately sticky, moderately plastic; common fine roots throughout; many fine tubular pores; many distinct irregular carbonate masses throughout; 40 percent gravel, 10 percent cobbles, 1 percent stones; violently effervescent (31 percent calcium carbonate equivalent); moderately alkaline (pH 8.4); gradual wavy boundary.(20 to 40 cm thick)

Bk--94 to 122 cm; yellowish red (5YR 4/6) broken face, very gravelly loam, brown (7.5YR 4/4) broken face, moist; weak fine subangular blocky structure, and weak fine subangular blocky structure; moderately hard, firm, moderately sticky, moderately plastic; common fine roots throughout; many fine tubular pores; common distinct irregular carbonate masses throughout; 35 percent gravel, 2 percent cobbles, 1 percent stones; violently effervescent (19 percent calcium carbonate equivalent); moderately alkaline (pH 8.4); gradual wavy boundary. (0 to 40 cm thick)

BCk--122 to 200 cm; yellowish red (5YR 4/6) broken face, very gravelly loam, reddish brown (5YR 4/4) broken face, moist; massive; slightly hard, friable, slightly sticky, slightly plastic; common fine roots throughout; many fine tubular pores; common distinct irregular carbonate masses throughout; 35 percent gravel, 2 percent cobbles, 1 percent stones; violently effervescent (6 percent calcium carbonate equivalent); moderately alkaline (pH 8.2).

TYPE LOCATION: Sublette County, Wyoming; located approximately 520 ft. south and 520 ft. east of the NW corner. of section 3, T 31N, R 114W; USGS Red Castle Creek, Wyoming topographic quadrangle; 42 degrees 42 minutes 27.00 seconds north latitude and 110 degrees 24 minutes 51.00 seconds west longitude.

RANGE IN CHARACTERISTICS:
Soil temperature: 1.7 to 3.3 degrees C.
Thickness of mollic epipedon: 20 to 35 cm.
Depth to argillic horizon: 8 to 19 cm.
Depth to calcic horizon: 40 to 75 cm.

A horizon(s)
Clay content: 18 to 25 percent
Fragment content: 15 to 35 percent
Fragment size and content: 15 to 35 percent gravel; 0 to 10 percent cobbles
Reaction: pH 6.6 to 7.3
Organic matter content: 2.0 to 4.0 percent

Bt horizon(s)
Texture: gravelly sandy clay loam, gravelly clay loam
Clay content: 25 to 35 percent
Fragment content: 15 to 35 percent
Fragment size and content: 15 to 35 percent gravel; 0 to 10 percent cobbles
Reaction: pH 6.6 to 7.3
Organic matter content: 2.0 to 4.0 percent

Btk1 horizon(s)
Texture: very gravelly clay loam, very gravelly sandy clay loam
Clay content: 25 to 35 percent
Fragment content: 35 to 60 percent
Fragment size and content: 2 to 7 percent carbonate nodules paragravel; 30 to 55 percent gravel; 2 to 10 percent cobbles
Calcium carbonate equivalent: 1 to 4 percent
Reaction: pH 6.8 to 7.6

Btk2 horizon(s)
Texture: very gravelly sandy clay loam, very gravelly clay loam
Clay content: 25 to 35 percent
Fragment content: 35 to 60 percent
Fragment size and content: 2 to 7 percent carbonate nodules paragravel; 35 to 55 percent gravel; 0 to 15 percent cobbles; 0 to 5 percent stones
Calcium carbonate equivalent: 5 to 15 percent
Reaction: pH 7.8 to 8.2

Bkk horizon(s)
Texture: very gravelly sandy clay loam, very gravelly loam
Clay content: 18 to 26 percent
Carbonate clay content: 4 to 8 percent
Fragment content: 35 to 60 percent
Fragment size and content: 35 to 55 percent gravel; 0 to 10 percent cobbles; 0 to 5 percent stones
Calcium carbonate equivalent: 25 to 40 percent
Sodium adsorption ratio: 0 to 5
Reaction: pH 7.9 to 8.4

Bk horizon(s)
Texture: very gravelly sandy clay loam, very gravelly loam
Clay content: 18 to 26 percent
Fragment content: 35 to 60 percent
Fragment size and content: 35 to 55 percent gravel; 0 to 10 percent cobbles; 0 to 5 percent stones
Calcium carbonate equivalent: 15 to 25 percent
Sodium adsorption ratio: 0 to 5
Reaction: pH 7.9 to 8.4

BCk horizon(s)
Texture: very gravelly sandy loam, very gravelly loam
Clay content: 15 to 22 percent
Fragment content: 35 to 60 percent
Fragment size and content: 35 to 55 percent gravel; 0 to 10 percent cobbles; 0 to 5 percent stones
Calcium carbonate equivalent: 5 to 15 percent
Sodium adsorption ratio: 0 to 5
Reaction: pH 7.9 to 8.4

COMPETING SERIES:
Cavemountain (NV) - has a lithic contact at depths of 100 cm or less.
Hodden (CO) - has a lithologic discontinuity.
Hoodling (CO) - peak precipitation occurs during July and August.
Latigo (ID) - has a xeric moisture regime.
Maciver (MT) - does not have secondary carbonates in any part of the argillic.
Nurkey (ID) - has a xeric moisture regime.
Teeler (WY) - does not have secondary carbonates in any part of the argillic.

GEOGRAPHIC SETTING:
Landform - outwash terraces, fan remnants.
Elevation - 2,286 to 2,529 meters.
Slope - 1 to 6 percent.
Parent material - alluvium and outwash derived from metamorphic and sedimentary rock.
Climate - long, cold winters; cool, moist springs; short, cool summers.
Mean annual precipitation - 381 to 483 mm with peak periods of precipitation occurring during the spring.
Mean annual air temperature - 0.6 to 1.7 degrees C.
Frost-free period - 25 to 45 days.

GEOGRAPHICALLY ASSOCIATED SOILS: None Listed.

DRAINAGE AND PERMEABILITY: Well drained, moderate permeability.

USE AND VEGETATION: Wilhelm soils are primarily used for rangeland. The potential native vegetation is mainly mountain big sagebrush, Letterman's needlegrass, snowberry, and Idaho fescue.

DISTRIBUTION AND EXTENT: Wilhelm soils are of small extent in southwestern Wyoming. MLRAs 34A and 43B.

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

SERIES PROPOSED: Sublette County, Wyoming, 2011. The series name is derived from a local landmark.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - 0 to 28 cm (A, Bt horizons);
Argillic horizon - 13 to 64 cm (Bt, Btk1, Btk2 horizons);
Calcic horizons - 64 to 122 cm (Bkk, Bk horizons); and a
Particle-size control section - from 13 to 63 cm (Bt, Btk1, and part of the Btk2 horizons).

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

Taxonomic version: Eleventh Edition: 2010

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National Cooperative Soil Survey
U.S.A.