LOCATION OMSRUD MNEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Typic Hapludolls
TYPICAL PEDON: Omsrud loam with a slope of 13 percent in a cultivated field. (Colors are for moist soil unless otherwise noted)
Ap--0 to 9 inches; very dark gray (10YR 3/1) loam, dark gray (10YR 4/1) dry; weak fine subangular blocky structure; friable; about 2 percent gravel; neutral; abrupt smooth boundary. (7 to 10 inches thick)
Bw--9 to 18 inches; dark yellowish brown (10YR 4/4) clay loam; moderate medium subangular blocky structure; friable; about 2 percent gravel; neutral; gradual wavy boundary. (8 to 28 inches thick)
Bk--18 to 36 inches; brown (10YR 5/3) loam; weak medium subangular blocky structure; friable; common threads and masses of calcium carbonate; about 3 percent gravel; violently effervescent; moderately alkaline; gradual wavy boundary. (0 to 30 inches thick)
C--36 to 80 inches; light olive brown (2.5Y 5/4) loam; massive; friable; few fine distinct yellowish brown (10YR 5/6) relic Fe concentrations; few threads of calcium carbonate; about 5 percent gravel; strongly effervescent; slightly alkaline.
TYPE LOCATION: Renville County, MN; about 4.5 miles east and 1.5 miles north of Buffalo Lake; 2550 north and 200 feet west of the southeast corner of sec. 23, T. 115 N., R. 31 W.; USGS Lake Allie quadrangle, latitude 44 degrees 45 minutes 12 seconds N; longitude 94 degrees 31 minutes 8 seconds W.
RANGE IN CHARACTERISTICS: The mollic epipedon ranges from 7 to 20 inches in thickness. Depth to calcium carbonates is quite variable within short horizontal distances and ranges from 18 to 50 inches. The 10 to 40 inch particle size control section ranges from 18 to 30 percent clay and 30 to 60 percent sand. Rock fragments, of mixed lithology, range from 2 to 10 percent by volume of the profile.
The Ap or A horizon has hue of 10YR, value of 2 or 3, and chroma of 1 to 3. It is typically loam but includes clay loam. Reaction is moderately acid to neutral.
The Bw horizon has hue of 10YR, value of 4 or 5, and chroma of 3 or 4. It is loam or clay loam. Reaction is moderately acid to neutral.
The Bk horizon has hue of 2.5Y or 10YR, value of 4 to 6 and chroma of 3 or 4. It is typically loam, sandy loam or clay loam. Reaction is slightly alkaline or moderately alkaline. Secondary calcium carbonates are common to many in the form of threads and masses.
Some pedons have a BC horizon.
The C horizon has hue of 2.5Y or 10YR, value of 4 to 6 and chroma of 2 to 4. The moderately coarse substratum phase has textures of loam, fine sandy loam or sandy loam. It has 12 to 22 percent clay and more than 40 percent total sand. The moderately fine substratum phase has textures of loam or clay loam. It has 20 to 30 percent clay and less than 45 percent total sand. Reaction is slighlty alkaline or moderately alkaline. Redox features are considered as relic as they do not relate to present day soil saturation.
COMPETING SERIES: These are Arbor, Aredale, Bode, Clarion, Cresken, Everly, Farrar, Frontenac, Garmore, Kenyon, Limecreek, Liscomb, Moland, Neeper, Ocheyedan, Ostrander and Rossfield series. Arbor, Cresken, Kenyon and Liscomb soils have firm glacial till with a bulk density of more than 1.60 g/cc in the lower on third of the series control section. Aredale, Everly, Moland, Ocheyedan and Ostrander soils have a lithologic discontinuity in the control section and have less than 2 percent rock fragments in the upper one fourth of the series control section. Bode soils have a lithologic discontinuity in the series control section and have less than 30 percent sand in the upper one fourth of the series control section. Clarion soils have saturation with water in the lower third of the series control section. Farrar soils have a lithologic discontinuity in the control section and have less than 18 percent clay in the upper one third of the series control section. Frontenac soils have 35 to 75 percent rock fragments in the lower third of the series control section. Garmore soils have free carbonates at depths of more than 50 inches. Limecreek and Rossfield soils have a paralithic contact at depths of less than 40 inches. Neeper soils do not have free carbonates in the control section.
GEOGRAPHIC SETTING: Omsrud soils have convex or linear slopes on ground moraines. Slopes gradients range from 5 to 40 percent. These soils formed in calcareous loamy glacial till of late Wisconsin age. Mean annual air temperature is 45 to 50 degrees F. Mean annual precipitation is 25 to 30 inches. Frost free days range from 125 to 165. Elevation ranges from 700 to 1600.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Canisteo, Clarion, Crippin, Nicollet, Okoboji, Storden, Swanlake and Webster soils. The poorly drained Canisteo and somewhat poorly drained Crippin soils are calcareous and are lower on the landscape. The well drained Clarion soils are on nearly level summits, sideslopes or convex rises. The somewhat poorly drained Nicollet and poorly drained Webster soils are lower on the landscape. The very poorly drained Okoboji soils are in closed depressions. The well drained Storden and Swanlake soils are on higher lying convex knolls and shoulder slopes.
DRAINAGE AND PERMEABILITY: Well drained. Surface runoff is moderate to high. Permeability is moderate.
USE AND VEGETATION: Mostly cultivated with corn, soybeans, small grain, and legume hay being the major crops. Native vegetation is tall grass prairie.
DISTRIBUTION AND EXTENT: South-central Minnesota and north-central Iowa in MLRA-103. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota
SERIES ESTABLISHED: Renville County, Minnesota, 1995.
REMARKS: Diagnostic horizons and features recognized in this pedon are: mollic epipedon - the zone from the surface to a depth of 9 inches (Ap horizon); cambic horizon - the zone from 9 to 18 inches (Bw horizon); calcic horizon - the zone from 18 to 36 inches (Bk horizon); udic moisture regime.
This series replaces the Clarion series on steeper slopes. Clarion soils have saturation with water in the lower one third of the series control section.
ADDITIONAL DATA: Soil Interpretation Record MN0781.