LOCATION FORMAN ND+MN SDEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Calcic Argiudolls
TYPICAL PEDON: Forman clay loam - in a cultivated field. (Colors are for dry soil unless otherwise stated)
Ap--0 to 8 inches; very dark gray (10YR 3/1) clay loam, black (10YR 2/1) moist; weak fine granular structure; hard, friable; many fine roots; many fine pores; neutral; abrupt smooth boundary. (Combined A horizons 4 to 10 inches thick)
Bt1--8 to 14 inches; brown (10YR 4/3) clay loam, dark brown (10YR 3/3) moist; moderate medium prismatic and moderate medium and fine angular blocky structure; very hard, friable; common fine roots; many faint very dark grayish brown (10YR 3/2) moist clay films on faces of peds; 1/8 to 1 inch black (10YR 2/1) moist tongues of A horizon; neutral; gradual smooth boundary.
Bt2--14 to 17 inches; grayish brown (2.5Y 5/2) clay loam, dark grayish brown (2.5Y 4/2) moist; moderate medium prismatic and moderate medium subangular blocky structure; very hard, friable; few fine roots; many distinct clay films on faces of peds; strong effervescence in the interior of prisms and blocks; slightly alkaline; clear wavy boundary. (Combined Bt horizons 5 to 19 inches thick)
Bk--17 to 44 inches; light yellowish brown (2.5Y 6/4) clay loam, light olive brown (2.5Y 5/4) moist; weak coarse prismatic structure; very hard, friable; many fine masses of carbonates; violent effervescence; moderately alkaline; diffuse wavy boundary. (7 to 30 inches thick)
Bky--44 to 60 inches; light yellowish brown (2.5Y 6/4) clay loam, grayish brown and light olive brown (2.5Y 5/2 and 5/4) moist; few fine distinct light olive brown (2.5Y 5/6) moist mottles; weak coarse and fine subangular blocky structure; friable; common fine masses of carbonates; many small nests of gypsum crystals; strong effervescence; moderately alkaline.
TYPE LOCATION: Sargent County, North Dakota; about 1/4 mile north of Forman; 1250 feet east and 150 feet south of northwest corner, sec. 18, T. 130 N., R. 55 W.
RANGE IN CHARACTERISTICS: The soil contains as much as 20 percent by volume pebbles, cobbles, and boulders throughout. Stony and cobbly phases are recognized. The mollic epipedon ranges from 7 to 16 inches in thickness.
The A horizon has hue of 10YR, value of 3 or 4 and 2 moist, and chroma of 1. It typically is loam or clay loam, but the range includes silt loam and silty clay loam. It is neutral or slightly alkaline.
The Bt horizon has hue of 10YR or 2.5Y, value of 4 or 5 and 3 or 4 moist, and chroma of 1 to 4. It averages between 30 and 35 percent clay, but ranges to 40 percent in thin layers or horizons in some pedons. The B/A clay ratio ranges from 1.2 to 1.3. It is neutral or slightly alkaline. It has moderate or strong medium or fine prismatic and angular or subangular blocky structure. Peds in the Bt horizon have common or many, faint or distinct clay films.
The Bk horizons have hue of 10YR or 2.5Y, value of 5 to 7 and 4 to 6 moist, and chroma of 2 to 4. They are clay loam or loam. They are slightly alkaline or moderately alkaline and contain both diffuse and segregated carbonates. Some pedons do not have a Bky horizon.
Some pedons have a C horizon below the Bk or Bky horizon. The C horizon where present, has hue of 10YR or 2.5Y, value of 4 to 6 and 3 to 5 moist, and chroma of 2 to 6. It is clay loam or loam. It is slightly alkaline or moderately alkaline.
COMPETING SERIES: These are the Bottineau, Doughty and Sipple series. Bottineau soils have uncoated sand grains on faces of peds in the A and B horizons. Doughty and Sipple soils are on fans and terraces and have gravelly or very gravelly C horizons.
GEOGRAPHIC SETTING: Forman soils are on level to steep till plains and moraines. Slope gradient commonly is 1 to 4 percent, but ranges from 0 to 30 percent. The soils formed in calcareous loam or clay loam glacial till. Mean annual air temperature ranges from 36 to 48 degrees F, and the mean annual precipitation is 15 to 25 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Aastad, Barnes, Buse, Parnell and Tonka soils. Aastad, Barnes and Buse soils do not have an argillic horizon. Aastad soils are in swales and on flats. Barnes soils are on convex slopes. Buse soils are on the convex hilltops and ridges. Parnell and Tonka soils have an aquic moisture regime and are in depressions.
DRAINAGE AND PERMEABILITY: Well drained. Runoff is low to very high depending on slope. Permeability is moderate in the solum, and moderately slow or slow in the substratum.
USE AND VEGETATION: Cultivated areas are used for growing small grains, corn, hay and pasture. Native vegetation is medium and tall prairie grasses.
DISTRIBUTION AND EXTENT: Eastern North Dakota, northeastern South Dakota, and western Minnesota. Forman soils are extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota
SERIES ESTABLISHED: Sargent County, North Dakota, 1959.
REMARKS: Revised 2/95.
Diagnostic horizons and features recognized in this pedon are: mollic epipedon - the zone from the surface of the soil to a depth of 14 inches (Ap and Bt1 horizons); argillic horizon - the zone from 8 to 17 inches (Bt1 and Bt2 horizons).
ADDITIONAL DATA: Refer to pages 92-105 in the Soil Survey Investigation Report No. 2.