LOCATION SELKIRK                 MI+WI

Established Series
Rev. RWJ-EPW-WEF
08/2012

SELKIRK SERIES

The Selkirk series consists of very deep, somewhat poorly drained soils formed in clayey till on moraines and till plains. Slope ranges from 0 to 6 percent. Mean annual precipitation is about 762 mm (30 inches), and mean annual temperature is about 6.7 degrees C (44 degrees F).

TAXONOMIC CLASS: Fine, mixed, semiactive, frigid Aquic Glossudalfs

TYPICAL PEDON: Selkirk silt loam, on a 2 percent slope in a cultivated field on a till plain. (Colors are for moist soil unless otherwise stated.)

Ap--0 to 18 cm (7 inches); dark gray (10YR 4/1) silt loam, light brownish gray (10YR 6/2) dry; weak fine granular structure; friable; many fine roots; slightly acid; abrupt smooth boundary. [15 to 20 cm (6 to 8 inches) thick]

E--18 to 30 cm (7 to 12 inches); light brownish gray (10YR 6/2) silt loam; weak medium platy structure; friable; many fine roots; few medium prominent yellowish brown (10YR 5/6) masses of oxidized iron; slightly acid; abrupt irregular boundary. [8 to 18 cm (3 to 7 inches) thick]

E/B--30 to 41 cm (12 to 16 inches); light brownish gray (10YR 6/2) silt loam (E); weak medium subangular blocky structure; friable; reddish brown (5YR 5/3) clay (Bt); strong medium subangular blocky structure; very firm; few fine roots; moderately acid; clear irregular boundary. [0 to 20 cm (8 inches) thick]

Bt--41 to 56 cm (16 to 22 inches); reddish brown (5YR 5/3) clay; interfingering and ped coatings of light brownish gray (10YR 6/2) silt loam; strong medium angular blocky structure; very firm; few fine roots along ped faces; many medium faint olive gray (5Y 4/2) iron depletions; many medium prominent yellowish brown (10YR 5/6) masses of oxidized iron; moderately acid; abrupt wavy boundary. [15 to 41 cm (6 to 16 inches) thick]

C--56 to 152 cm (22 to 60 inches); reddish brown (5YR 5/3) clay; moderate medium angular blocky fragments; very firm; many coarse prominent olive (5Y 5/3) iron depletions; slightly effervescent; moderately alkaline.

TYPE LOCATION: Alpena County, Michigan; 600 feet east and 400 feet south of the center of sec. 16, T. 30 N., R. 6 E.

RANGE IN CHARACTERISTICS:
Thickness of the solum: 41 to 76 cm (16 to 30 inches)
Particle-size control section: weighted average clay content ranges from 45 to 60 percent
Rock fragment content: 0 to 10 percent gravel and cobbles throughout the profile

A horizon, where present:
Thickness: 2.5 to 8 cm (1 to 3 inches)
Hue: 10YR
Value: 2 or 3
Chroma: 1 to 3
Texture: silty clay loam, clay loam, silt loam, loam, or sandy loam
Reaction: moderately acid to neutral

Ap horizon:
Hue: 10YR
Value: 4 or 5
Chroma: 1 or 2
Texture: silty clay loam, clay loam, silt loam, loam, or sandy loam
Reaction: moderately acid to neutral

Some pedons do not have an E/B horizon and the E horizon extends as coatings on ped faces and in root channels and worm casts into the upper part of the Bt horizon.

Bt horizon:
Hue: 5YR to 10YR
Value: 4 or 5
Chroma: 3 or 4
Texture: clay or silty clay
Reaction: moderately acid to neutral

C horizon:
Hue: 2.5YR to 10YR
Value: 4 to 6
Chroma: 2 to 4
Texture: clay or silty clay

COMPETING SERIES: These are the Bowers, Kawkawlin, and Pinewood series. Bowers and Kawkawlin soils average less than 45 percent clay in the particle-size control section. Pinewood soils are deeper than 76 cm (30 inches) to the base of the argillic horizon.

GEOGRAPHIC SETTING: Selkirk soils are on till plains and moraines. Slope ranges from 0 to 6 percent. These soils formed in clayey till. Mean annual precipitation ranges from 660 to 813 mm (26 to 32 inches). Mean annual temperature ranges from 5.6 to 7.8 degrees C (42 to 46 degrees F).

GEOGRAPHICALLY ASSOCIATED SOILS: The well drained or moderately well drained Kent soils and the poorly drained or very poorly drained Pickford soils are in a drainage sequence with Selkirk soils. Allendale and Manistee soils are associated in some areas where sandy layers overlie the clay till. Kawkawlin soils are associated on some till plains and moraines.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Somewhat poorly drained. Potential for surface runoff is medium or high. Saturated hydraulic conductivity is moderately low. Permeability is slow.

USE AND VEGETATION: A large part is under cultivation. Wheat, oats, and hay are the principal crops. A small amount of corn is grown. A smaller part, especially those areas that lack adequate drainage, is in permanent pasture or in woodland. Native vegetation is chiefly hardwood forest of sugar maple, white spruce, American beech, American elm and ironwood. Balsam fir, northern white cedar and hemlock are in some areas.

DISTRIBUTION AND EXTENT: MLRAs 94A, 94B, and 98 in northern Michigan and northeastern Wisconsin. The series is of moderate extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: AMHERST, MASSACHUSETTS

SERIES ESTABLISHED: Ogemaw County, Michigan, 1923.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: from the surface to a depth of 18 cm (7 inches) (Ap horizon).
Albic horizon: from a depth of 18 to 41 cm (7 to 16 inches) (E horizon and E part of the E/B horizon).
Argillic horizon: from a depth of 41 to 56 cm (16 to 22 inches) (Bt horizon).
Aquic conditions: reduced matrix color or redoximorphic features in all horizons below a depth of 18 cm (7 inches).

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National Cooperative Soil Survey
U.S.A.