LOCATION DORA MN+MI NY WIEstablished Series
TAXONOMIC CLASS: Clayey, smectitic, euic, frigid Terric Haplosaprists
TYPICAL PEDON: Dora mucky peat in a shallow depressional area on a lacustrine plain. (Colors are for moist soil unless otherwise noted.)
Oe--0 to 12 inches; black (10YR 2/1) broken face, rubbed and pressed mucky peat; about 50 percent fiber, 20 percent rubbed; weak medium blocky structure; very friable; primarily herbaceous fibers; moderately acid; clear smooth boundary.
Oa1--12 to 26 inches; black (10YR 2/1) broken face, rubbed and pressed muck; about 10 percent fiber, 3 percent rubbed; moderate medium blocky structure that parts to moderate fine subangular blocky and granular; very friable; primarily herbaceous fiber, moderately acid; clear wavy boundary.
Oa2--26 to 32 inches; black (10YR 2/1) broken face, rubbed and pressed muck; about 7 percent fiber, 2 percent rubbed; moderate medium and coarse blocky structure; very friable; primarily herbaceous fibers; about 10 percent mineral material; moderately acid; clear smooth boundary.
A--32 to 36 inches; black (10YR 2/1) mucky silty clay loam, about 20 percent organic material; massive; firm; slightly acid; clear wavy boundary. (0 to 6 inches thick)
Cg1--36 to 42 inches; gray (5Y 5/1) and dark gray (5Y 4/1) silty clay loam; massive; firm; common medium prominent strong brown (7.5YR 5/6) and few fine prominent yellowish brown (10YR 5/4) Fe concentrations; slightly acid; gradual wavy boundary.
Cg2--42 to 52 inches; olive gray (5Y 4/2) silty clay; massive; firm; common medium prominent strong brown (7.5YR 5/6) and yellowish red (5YR 4/6) Fe concentrations; slightly acid; gradual wavy boundary.
Cg3--52 to 60 inches; gray (5Y 5/1) silty clay; massive; few fine and medium prominent yellowish red (5YR 4/6) Fe concentrations; slightly effervescent; slightly alkaline.
TYPE LOCATION: Itasca County, Minnesota; about 6 miles north and 3 miles east of the town of Deer River; 1,300 feet east and 700 feet north of the southwest corner of section 11, T. 57 N., R. 27 W.
RANGE IN CHARACTERISTICS: The depth to the clayey material commonly is 20 to 42 inches and ranges between 16 and 51 inches. The material above the C horizon in most pedons primarily is from herbaceous plants, but in some it is predominantly from woody plants. Some pedons contain wood fragments of twigs, branches, or logs which range from 1/8 to 5 inches in diameter and amount to less than 15 percent of the volume. The organic portion of the control section has 10YR, 7.5YR, or 5YR hue; value of 2 or 3; and chroma of 0, 1, or 2. Some pedons exhibit decrease in value or chroma when exposed to the air. The organic portion of the control section ranges from pH 4.5 to pH 7.8 in 0.01M calcium chloride and does not have free carbonates. The mineral part ranges from slightly acid to moderately alkaline.
The surface tier, exclusive of loose surface litter or mosses, is comprised of mucky peat or muck with an unrubbed fiber content that ranges from about 20 percent to 50 percent of the organic volume. Rubbed fiber content ranges from less than 10 percent to 20 percent. Surface layers of both muck and mucky peat are recognized.
The subsurface tier is dominated by muck that comprises more than half of the organic material. The unrubbed fiber content ranges from less than 10 percent to 50 percent of the organic volume and is less than 10 percent after rubbing.
In some pedons, layers of mucky peat are within the organic portion of the control section but have a combined thickness of less than 10 inches. A thin tier of coprogenous material, less than 6 inches thick, is between the sapric material and the mineral soil material in some pedons.
The A horizon has hue of 10YR or 2.5Y, value of 2 or 3, and chroma of 0 to 2. It is mucky silty clay loam or mucky silt loam.
The C horizon has 5Y, 2.5Y, 10YR, 7.5YR, 5YR or 2.5YR hue; value of 4 to 6; and chroma of 1 to 6. It is silty clay, clay, silty clay loam, clay loam, or sandy clay. Thin layers in some pedons have more sand or silt and less clay.
Cd horizons occur below 60 inches in some pedons.
COMPETING SERIES: There are no competing series. Other closely related series are the Cathro, Lupton, Markey, and Rondeau series. Cathro soils have less clay in the underlying mineral soil at depths less than 51 inches. Lupton soils formed primarily in woody material greater than 51 inches thick. Markey soils have sandy 2C horizons at depths less than 51 inches. Rondeau soils have marly 2C horizons at depths less than 51 inches.
GEOGRAPHIC SETTING: Dora soils are in depressions within till plains, moraines, glacial lake plains, and outwash plains. Individual bodies range in size from a few acres to several hundred acres. Slope gradients are 0 to 1 percent. The mean annual precipitation ranges from 22 to 28 inches. Mean annual air temperature ranges from 36 to 42 degrees F. Frost-free days range from 88 to 135. Elevation above sea level ranges from 1000 to 1600 feet.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Brickton, Carbondale, Fayal, Indus, Lupton, Seelyeville, and Wildwood soils. Brickton and Indus are poorly drained clayey soils occupying adjacent nearly level areas. Carbondale and Seelyeville soils have dominantly sapric material more than 51 inches thick. Very poorly drained Fayal soils formed in dense clayey till. Wildwood soils are very poorly drained, clayey soils having a histic epipedon.
DRAINAGE AND PERMEABILITY: Very poorly drained. Runnoff is negligible. Permeability is moderate or moderately rapid in the organic layers and very slow in the clayey material. Seasonal high saturation is at depths of plus 1 to 0 feet at some time from April through June and October through November normal years for the undrained phase. It is at plus 3 feet to 0 feet from January to December in most years for the ponded phase.
USE AND VEGETATION: Most of areas are alder, aspen, dogwood, grasses, reeds, and sedges. Some areas are wooded with American elm, black ash, and black spruce as the principal species.
DISTRIBUTION AND EXTENT: Northern Minnesota and Michigan and possibly northern Wisconsin. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota
SERIES ESTABLISHED: Itasca County, Minnesota, 1982.
REMARKS: This covers a portion of inactive Suamico series. Diagnostic horizons and soil features in this pedon are: sapric material from the surface to 32 inches (Oe, Oa1 and Oa2 horizons); terric subgroup- mineral soil material from 32 to 60 inches (A, Cg1, Cg2 and Cg3 horizons).