LOCATION LOURIS MNEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Aquic Calciudolls
TYPICAL PEDON: Louris silt loam with a slightly convex slope of 1 percent on a ground moraine in a cultivated field. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 8 inches; black (10YR 2/1) silt loam, very dark gray (10YR 3/1) dry; weak fine subangular blocky structure; friable; strongly effervescent; slightly alkaline; abrupt smooth boundary. (6 to 10 inches thick)
Ak--8 to 13 inches; very dark gray (10YR 3/1) silt loam, dark gray (10YR 4/1) dry; weak very fine subangular blocky structure; friable; carbonates disseminated throughout; violently effervescent; moderately alkaline; clear smooth boundary. (0 to 10 inches thick)
Bk--13 to 20 inches; dark grayish brown (2.5Y 4/2) silt loam; weak fine subangular blocky structure; friable; carbonates disseminated throughout; violently effervescent; moderately alkaline; clear smooth boundary. (6 to 12 inches thick)
BC--20 to 27 inches; olive brown (2.5Y 4/4) silt loam; weak medium subangular blocky structure; friable; strongly effervescent; slightly alkaline; gradual smooth boundary.
(0 to 10 inches thick)
C1--27 to 31 inches; light olive brown (2.5Y 5/4) loam; massive; friable; common fine distinct grayish brown (2.5Y 5/2) Fe depletions; strongly effervescent; slightly alkaline; abrupt smooth boundary. (6 to 12 inches thick)
2C2--31 to 80 inches; light olive brown (2.5Y 5/4) loam; massive; friable; common fine and medium distinct grayish brown (2.5Y 5/2) Fe depletions and common fine distinct yellowish brown (10YR 5/6) Fe concentrations; 6 percent gravel; carbonates segregated in few white (10YR 8/2) fine and medium soft masses; strongly effervescent; slightly alkaline.
TYPE LOCATION: Renville County, Minnesota; about 4 miles east and 2.5 miles north of Minnesota Falls; about 2,125 feet north and 250 feet east of the southwest corner of sec. 24, T. 116 N., R. 38 W.; USGS Minnesota Falls quadrangle, latitude 44 degrees 50 minutes 17 seconds N. and longitude 95 degrees 22 minutes 48 seconds W.
RANGE IN CHARACTERISTICS: The thickness of the mollic epipedon ranges from 8 to 16 inches. The thickness of the silty mantle and depth to glacial till ranges from 24 to 40 inches. The upper sediment typically does not have rock fragments, but in some pedons it contains up to 2 percent by volume. The glacial till contains 2 to 10 percent, by volume, of coarse fragments of mixed lithology. The calcic horizon is within depths of 40 inches and has 15 to 40 percent calcium carbonate equivalent. The profile is calcareous throughout and the reaction is mildly alkaline or moderately alkaline. The control section has 18 to 35 percent clay.
The A, Ap and Ak horizons have hue of 10YR or 2.5Y, value of 2 or 3, and chroma of 1 or 2. They are typically silt loam but the range includes silty clay loam.
The Bk horizon has hue of 10YR, value of 4 to 6, and chroma of 1 to 3, or a hue of 2.5Y, value of 4 to 6, and chroma of 2 to 4. It does not have distinct or prominent mottles. It is silt loam or silty clay loam. Carbonates are typically disseminated throughout the matrix but some pedons have a few threads or masses of segregated carbonates.
The C and 2C horizons have hue of 2.5Y, value of 4 to 6, and chroma of 3 to 6. Fe depletions are typically present. The C horizon is silt loam or loam. The 2C horizon is loam or clay loam.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: These soils have plane or slightly convex slopes with gradient of 1 to 3 percent on glacial till plains or ground moraines. The Louris soils formed in 24 to 40 inches of silty lacustrine sediments or loess and calcareous loam or clay loam glacial till. Mean annual air temperature is 45 to 48 degrees F. Mean annual precipitation is 22 to 26 inches. Frost free days range from 120 to 160. Elevation above sea level is 1000 to 1500 feet.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Crooksford and Leen soils which formed in similar sediments and Seaforth and Swanlake soils which formed entirely in glacial till. They are members of the same hydrosequence. The Crooksford and Swanlake soils are well drained and are on more sloping positions. The Seaforth soils are moderately well drained on similar positions. The Leen soils are poorly drained and are on lower positions.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained. Permeability is moderate. Surface runoff is moderately low. Depth to a seasonal high water table is at 1.5 to 2.5 feet at some time during November to May in most years.
USE AND VEGETATION: Nearly all of these soils are cultivated. Small grain, corn, and soybeans are the principal crops. Native vegetation is tall grass prairie.
DISTRIBUTION AND EXTENT: South Central Minnesota. Moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota
ESTABLISHED SERIES: Renville County, Minnesota, l995.
ADDITIONAL DATA: Soil Interpretations Record MN0829.
REMARKS: Diagnostic horizons and features recognized in this pedon are: mollic epipedon - the zone from the surface to 13 inches (Ap and Ak horizons); calcic horizon - the zone from 8 to 20 inches (Ak and Bk horizon); aquic subgroup - low chroma redox depletions within 40 inches (C1 and 2C2 horizons).