LOCATION DESIOUX MOEstablished Series
TAXONOMIC CLASS: Coarse-silty, mixed, superactive, mesic Cumulic Hapludolls
TYPICAL PEDON: DeSioux loam - on a 1 percent slope in a cultivated field. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 13 centimeters (0 to 5 inches); black (10YR 2/1) loam, dark grayish brown (10YR 4/2) dry; moderate fine subangular blocky structure; friable; common very fine and fine roots; common fine and few medium and coarse tubular pores; neutral; abrupt smooth boundary.
A1--13 to 48 centimeters (5 to 19 inches); black (10YR 2/1) silt loam, dark grayish brown (10YR 4/2) dry; moderate medium subangular blocky structure; friable; few very fine and fine roots; few fine and medium tubular pores; neutral; clear smooth boundary.
A2--48 to 81 centimeters (19 to 32 inches); 70 percent black (10YR 2/1), dark grayish brown and 30 percent very dark grayish brown (10YR 3/2) loam, dark grayish brown (10YR 4/2) and grayish brown (10YR 5/2) dry; moderate medium subangular blocky structure; friable; few very fine and fine roots; few coarse tubular pores; neutral; clear smooth boundary.
A3--81 to 104 centimeters (32 to 41 inches); 70 percent very dark grayish brown (10YR 3/2) and 30 percent very dark gray (10YR 3/1) loam, dark grayish brown (10YR 4/2) and grayish brown (10YR 5/2) dry; moderate medium subangular blocky structure; friable; few very fine and fine roots; few coarse tubular pores; neutral; abrupt smooth boundary. (Combined thickness of the A horizon is 61 to 114 centimeters 24 to 45 inches.)
Bw1--104 to 145 centimeters (41 to 57 inches); 60 percent dark grayish brown (10YR 4/2) and 40 percent dark brown (10YR 3/3) loam; weak medium subangular blocky structure; friable; few very fine and fine roots; common fine and medium tubular pores; neutral; clear smooth boundary.
Bw2--145 to 170 centimeters (57 to 67 inches); 70 percent brown (10YR 4/3) and 30 percent dark grayish brown (2.5Y 4/2) silt loam; weak medium prismatic structure; friable; few very fine and fine roots; common fine and medium tubular pores; common fine prominent strong brown (7.5YR 5/6) masses of oxidized iron (fe+3) in matrix; slightly acid; abrupt smooth boundary. (Combined thickness of the Bw horizon is 38 to 142 centimeters 15 to 56 inches.)
2C1--170 to 191 centimeters (67 to 75 inches); dark grayish brown (10YR 4/2) fine sand; single grain; loose; many fine interstitial pores; slightly alkaline; abrupt smooth boundary.
2C2--191 to 208 centimeters (75 to 82 inches); 40 percent grayish brown (2.5Y 5/2), 40 percent dark grayish brown (2.5Y 4/2), and 20 percent very dark gray (10YR 3/1) stratified silt loam and very fine sandy loam; massive; friable; common fine and medium tubular pores; common fine prominent yellowish red (5YR 5/6) and dark reddish brown (5YR 3/4) masses of oxidized iron (fe+3) in matrix; neutral. (Combined thickness of the 2C horizon is 0 to 104 centimeters 0 to 41 inches.)
TYPE LOCATION: St. Charles County, Missouri; 1,423 feet West and 237 feet North from the Southeast corner of Section 32, Township 48N, Range 5E of the 5th Principal Meridian. St. Charles, Missouri USGS quadrangle; latitude 38 degrees, 52 minutes 9 seconds N. and longitude 90 degrees, 28 minutes, 41 seconds W. UTM 718,797 meters easting, 4,305,280 meters northing, Zone 15, NAD 83.
RANGE IN CHARACTERISTICS:
Thickness of mollic epipedon: 61 to 114 centimeters (24 to 45 inches). Depth to top of the cambic horizon: 61 to 114 centimeters (24 to 45 inches). Depth to the base of the cambic horizon: 152 to greater than 203 centimeters (60 to 80 inches)
Particle-size control section: averages 10 to 18 percent clay
Solum thickness: 145 to more than 203 centimeters (57 to 80 inches)
Depth to carbonates: commonly more than 203 centimeters (80 inches)
Ap and A horizons
Hue: 10YR
Value: 2 or 3, moist; 4 or 5, dry
Chroma: 1 to 3
Texture: silt loam, very fine sandy loam, or loam
Average clay content: 10 to 18 percent
Average sand content: 5 to 50 percent
Reaction: moderately acid to slightly alkaline
Bw horizon
Hue: 10YR or 2.5Y
Value: 3 or 4
Chroma: 2 to 4
Texture: silt loam, loam, or very fine sandy loam
Average clay content: 5 to 18 percent
Average sand content: 5 to 60 percent (50 percent or more very fine sand)
Reaction: moderately acid to slightly alkaline
2Bw horizon (where present)
Hue: 10YR or 2.5Y
Value: 4 or 5
Chroma: 1 to 4
Texture: commonly silt loam, very fine sandy loam, or silty clay loam, less commonly silty clay, or clay
Average clay content: 5 to 55 percent
Average sand content: 5 to 60 percent (50 percent or more very fine sand)
Reaction: neutral or slightly alkaline
2C horizon (where present)
Hue: 10YR or 2.5Y
Value: 3 to 5
Chroma: 1 to 3
Texture: commonly silt, silt loam, very fine sandy loam, loamy fine sand, or fine sand, less commonly silty clay
Average clay content: 5 to 45 percent
Average sand content: 10 to 90 percent
Reaction: neutral or slightly alkaline
COMPETING SERIES: There are no competing series. Similar series include Lowmo which has a thinner mollic epipedon and Lomax which has more sand in the control section.
GEOGRAPHIC SETTING: DeSioux soils are on nearly level, linear to convex terraces. These soils formed in Mississippi or Missouri River alluvium. Slopes are 0 to 2 percent. They are rarely flooded. The mean annual temperature ranges from 10 to 13 degrees C (50 to 55 degrees F), and mean annual precipitation ranges from 889 to 1020 millimeters (35 to 40 inches).
GEOGRAPHICALLY ASSOCIATED SOILS: The somewhat poorly drained Blas soils and the poorly drained Booker, Carlow, Portage, and SansDessein soils. All these soils contain more clay in the control section and occur on slightly lower positions.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained. The potential for runoff is negligible to low. Permeability is moderate. Saturated hydraulic conductivity (Ksat) is 4-14 micrometers per second. In undisturbed areas a apparent water table is at a depth of more than 122 cm (4 feet). These soils are subject to rare flooding.
USE AND VEGETATION: Most areas are used to grow soybeans and corn. The native vegetation is grasses.
DISTRIBUTION AND EXTENT: The Central Mississippi Valley Wooded Slopes, MLRA 115B, of east central Missouri. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Indianapolis, Indiana
SERIES ESTABLISHED: St. Charles County, Missouri, 2009.
REMARKS: These soils were previously included in the Lomax series in Missouri. They differ from the Lomax soils by being coarse-silty in the particle-size control section rather than coarse-loamy. The name is derived from a town near the type location.
Diagnostic horizons and features recognized in this pedon are: mollic epipedon - the zone from the surface of the soil to a depth of 104 centimeters (41 inches) (Ap and A horizons); cambic horizon - the zone from approximately 104 to 170 centimeters (41 inches to 67 inches) (Bw1 and Bw2 horizons).
ADDITIONAL DATA: Laboratory data University of Missouri, Columbia, Missouri; Pedon ID M0718330 is data for the OSD typical pedon; Pedons ID M0718336, M0718342, M0718331, M0718335, M0718333, and M0718340, are additional data used for the series range in characteristics.