LOCATION LAMOURE SD+MN MT NDEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, calcareous, frigid Cumulic Endoaquolls
TYPICAL PEDON: Lamoure silty clay loam - on a slope of 1 percent in a cultivated field. When described the soil was moist throughout. (Colors are for moist soil unless otherwise stated.)
A1--0 to 15 inches; black (N 2/0) silty clay loam, very dark gray (N 3/0) dry; weak fine granular structure; slightly hard, friable, slightly sticky; strong effervescence; moderately alkaline; clear wavy boundary.
A2--15 to 27 inches; black (10YR 2/1) silty clay loam, gray (10YR 5/1) dry; weak medium and coarse prismatic structure parting to weak fine subangular blocky; slightly hard, friable, slightly sticky; strong effervescence; moderately alkaline; gradual wavy boundary. (Combined A horizons 24 to 42 inches thick.)
Cg1--27 to 34 inches; dark gray (N 4/0) silty clay loam, gray (N 5/0) dry; vertical faces of peds very dark gray (N 3/0); weak fine subangular blocky structure; slightly hard, friable, slightly sticky; few fine prominent dark brown (10YR 3/3) redox concentrations; strong effervescence; moderately alkaline; gradual wavy boundary.
Cg2--34 to 43 inches; dark grayish brown (2.5Y 4/2) silt loam, grayish brown (2.5Y 5/2) dry; weak fine subangular blocky structure; slightly hard, friable; many fine distinct very dark gray (N 3/0) redox depletions and common fine prominent dark yellowish brown (10YR 4/4) redox concentrations; strong effervescence; moderately alkaline; clear wavy boundary.
Ab--43 to 52 inches; very dark gray (10YR 3/1) loam, very dark grayish brown (10YR 3/2) rubbed, gray (10YR 5/1) dry; weak fine subangular blocky structure; hard, friable, slightly sticky; few fine faint dark brown (10YR 3/3) redox concentrations; slight effervescence; moderately alkaline; abrupt wavy boundary.
C'g--52 to 60 inches; dark grayish brown (2.5Y 4/2) sandy loam, grayish brown (2.5Y 5/2) dry; massive; soft, very friable; few fine distinct olive brown (2.5Y 4/4) redox concentrations; slight effervescence; moderately alkaline.
TYPE LOCATION: Brookings County, South Dakota; about 1 mile west and 1.5 miles north of Bushnell; 1930 feet south and 100 feet east of the northwest corner of sec. 12, T. 110 N., R. 49 W.
RANGE IN CHARACTERISTICS: Depth to carbonates ranges from 0 to 10 inches. The soil is slightly alkaline or moderately alkaline throughout. The control section typically is a silty clay loam, but is silt loam in some pedons. Thickness of the mollic epipedon ranges from 24 to more than 60 inches. Buried A horizons are common below depths of 30 inches.
The A horizon is neutral or has hue of 10YR, 2.5Y, and 5Y; value of 2 or 3 and 3 to 5 dry; and chroma of 1 or less. It typically is silty clay loam, but is silt loam in some pedons.
The Cg horizon is neutral or has hue of 2.5Y or 5Y, value of 2 to 6 and 4 to 8 dry, and chroma of 2 or less. Chroma of 2 is only in the lower part. Redox features are variable, ranging from few fine faint to many prominent. In some pedons the Cg horizon contains few or common, fine to coarse accumulations of carbonates. The Cg horizon below depths of 40 inches has texture similar to the control section or is stratified loam, silt loam, sandy loam, silty clay loam, or clay. Some pedons are sand, gravelly sand, or loamy sand.
COMPETING SERIES: These are the Downata, Halleck, Inkom, Playmoor, and Rauville series. Downata soils have A horizons with chroma of 2 or 3. Halleck soils have mean annual precipitation of 10 to 12 inches and violent effervescence throughout. Inkom soils have cambic horizons. Playmoor soils contain more visible salts and have more exchangeable sodium. Rauville soils do not have mottles within depths of 40 inches and are very poorly drained.
GEOGRAPHIC SETTING: The Lamoure soils are on nearly level bottoms of glacial outwash valleys and on flood plains of major streams and tributaries within glacial till plains. Slopes are less than 2 percent. They formed in silty alluvium. Mean annual air temperature ranges from 36 to 48 degrees F, and mean annual precipitation ranges from 16 to 24 inches. Growing season is about 120 to 135 days; average growing season precipitation from 14 to 20 inches; and growing degree days are about 2500 to 3100.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Playmoor and Rauville soils and the Dovray, Forman, LaDelle, Lowe, Ludden, and Poinsett soils. Ludden and Playmoor soils are in similar landscapes. Ludden soils have a fine textured series control section. Rauville soils are in more depressed and sluggish drainageways. Dovray soils are deeper to carbonates, have a fine textured series control section, and are on similar landscapes. The well drained Forman soils have an argillic horizon and on adjacent uplands. The moderately well drained LaDelle soils do not have mottles within depths of 40 inches and are on slightly higher positions on the landscape. Lowe soils have a calcic horizon within 16 inches of the surface and have a fine-loamy series control section. They are on similar landscapes to the Lamoure soil. The well drained Poinsett soils have mollic epipedons less than 16 inches thick and are on adjacent uplands.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained or poorly drained. Surface runoff is low. Permeability is moderate or moderately slow. The water table is at depths of 0 to 2 feet, except during the growing season. Lamoure soils frequently flood from stream overflow.
USE AND VEGETATION: Much is in native hay and pasture. The better drained areas are cropped to corn, small grain, alfalfa, and feed grains. Native vegetation is mainly big bluestem, switchgrass, indiangrass, kentucky bluegrass, prairie cordgrass, little bluestem, sedges, and forbs.
DISTRIBUTION AND EXTENT: Northeastern South Dakota, eastern North Dakota, and western Minnesota. The series is of large extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota
SERIES ESTABLISHED: Lamoure County, North Dakota, 1914.
REMARKS: Diagnostic horizons and features recognized in this pedon are: mollic epipedon - the zone from the surface of the soil to a depth of about 27 inches (A1 and A2 horizons).