LOCATION POSEN MIEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Typic Eutrudepts
TYPICAL PEDON: Posen cobbly fine sandy loam - on a 1 percent north- facing slope in a forested area. (Colors are for moist soil unless otherwise stated).
Oe--1 to 0 inch; black (N 2/0) partially decomposed leaf forest litter; many very fine to medium roots. (0 to 3 inches thick)
A--0 to 3 inches; very dark gray (10YR 3/1) stony fine sandy loam, dark gray (10YR 4/1) dry; moderate medium granular structure; very friable; many very fine to medium and common coarse roots; about 3 percent gravel, 15 percent cobbles, and 15 percent stones; slightly acid; abrupt wavy boundary. (2 to 5 inches thick)
Bw1--3 to 10 inches; dark brown (10YR 3/3) stony silt loam; light yellowish brown (10YR 6/4) dry; moderate fine and medium subangular blocky structure; friable; common very fine to medium roots; about 5 percent gravel, 10 percent cobbles, and 15 percent stones; neutral; abrupt wavy boundary.
Bw2--10 to 16 inches; brown (10YR 4/3) very cobbly silt loam; moderate fine and medium subangular blocky structure; friable; common very fine to medium roots; about 10 percent gravel and 30 percent cobbles; neutral; clear wavy boundary. (Combined thickness of the Bw horizons is 10 to 20 inches.)
C--16 to 60 inches; brown (10YR 5/3) very cobbly fine sandy loam; massive; friable; few fine roots; about 30 percent gravel and 30 percent cobbles; violent effervescence; moderately alkaline.
TYPE LOCATION: Chippewa County, Michigan; about 1.5 miles northeast of the village of Johnswood; 2,400 feet east and 50 feet south of the northwest corner, sec. 8, T. 41 N., R. 7 E.
RANGE IN CHARACTERISTICS: Solum thickness and depth to free carbonates ranges from 15 to 25 inches. The solum ranges from medium acid to neutral. Rock fragments range from 15 to 35 percent in the A horizon and from 35 to 60 percent in the B and C horizons.
The A horizon has hue of 10YR or is neutral, value of 2 or 3, and chroma of 0 to 3. It is the cobbly or stony analogues fine sandy loam, sandy loam, or silt loam.
The Bw horizons have value of 3 or 4 and chroma of 2 to 4. They are very gravelly, very cobbly, or stony analogues of fine sandy loam, silt loam, or loam.
The C horizon has value of 5 to 7 and chroma of 3 or 4. It is very gravelly or very cobbly analogues of fine sandy loam, loam, or sandy loam.
COMPETING SERIES: This is the Beeskove series in the same family and the Emmet and Onaway series in closely related families. Beeskove soils are substantially drier in the soil moisture control section for the 120 days following the summer solstice. Emmet and Onaway soils have argillic horizons and fewer rock fragments throughout.
GEOGRAPHIC SETTING: Posen soils are on till plains and glacial lake benches. Slope gradients range from 0 to 35 percent. Mean annual temperature ranges from 38 to 42 degrees F. Mean annual precipitation ranges from 25 to 37 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Alpena, Longrie, Shelter, and Summerville soils. The Alpena soils are sandy-skeletal. Longrie and Summerville soils are underlain by limestone bedrock at depths less than 40 inches. These soils are on similar landscape positions. Shelter soils are somewhat poorly drained and occur on slightly lower landscape positions.
DRAINAGE AND PERMEABILITY: Well drained. Surface runoff is slow to rapid. Permeability is moderate.
USE AND VEGETATION: Most are as of this soil are forested. Vegetation consists of sugar maple, quaking aspen, balsam fir, yellow birch, northern red oak, red pine, American basswood, American beech, and white ash.
DISTRIBUTION AND EXTENT: Eastern Upper Peninsula and Northern Lower Peninsula of Michigan. The Posen series is inextensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota
SERIES ESTABLISHED: East Unit Hiawatha National Forest, Michigan, 1984.
REMARKS: Diagnostic horizons and features recognized in this pedon are: ochric epipedon - the zone from 0 to 3 inches (A horizon); cambic horizon - the zone from 3 to 16 inches (Bw1 and Bw2 horizon).