LOCATION WINFIELD MO+ILEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Oxyaquic Hapludalfs
TYPICAL PEDON: Winfield silt loam - on an 8 percent northwest facing slope in pasture. (Colors are for moist soil unless otherwise noted.)
Ap--0 to 6 inches; brown (10YR 4/3) silt loam, pale brown (10YR 6/3) dry; moderate fine granular structure; friable; common fine roots; few dark brown (10YR 3/3) stains; neutral; clear smooth boundary. (5 to 10 inches thick)
E--6 to 10 inches; brown (10YR 4/3) silt loam; weak medium subangular blocky structure; friable; common fine roots; slightly acid; clear smooth boundary. (0 to 6 inches thick)
BE--10 to 14 inches; dark yellowish brown (10YR 4/4) silt loam; moderate medium subangular blocky structure; friable; many fine roots; slightly acid; clear smooth boundary. (0 to 6 inches thick)
Bt1--14 to 22 inches; yellowish brown (10YR 5/4) silty clay loam; moderate fine subangular blocky structure; firm; common fine roots; many faint brown clay films on faces of peds; strongly acid; gradual smooth boundary.
Bt2--22 to 30 inches; yellowish brown (10YR 5/6) silty clay loam; strong medium subangular blocky structure; firm; few fine roots; many faint brown clay films on faces of peds; some peds coated with gray silt; common fine very dark brown iron and manganese concretions; very strongly acid; gradual smooth boundary.
Btg1--30 to 43 inches; variegated light brownish gray (10YR 6/2), brown (7.5YR 4/4) and yellowish brown (10YR 5/6) silty clay loam; moderate medium prismatic structure parting to weak medium subangular blocky; firm; few fine roots; many faint clay films on faces of peds; very thick light brownish gray clay coatings on flows on some vertical prism faces; many very dark brown iron and manganese concretions; very strongly acid; gradual smooth boundary.
Btg2--43 to 54 inches; gray (10YR 6/1) silty clay loam; moderate medium prismatic structure parting to weak medium subangular blocky; firm; few fine roots; many distinct clay films on vertical faces of prisms; few faint clay films on other faces of peds; many fine distinct dark yellowish brown (10YR 4/4) masses of iron accumulation in ped interiors; many soft very dark brown iron and manganese accumulations; very strongly acid; diffuse wavy boundary. (Combined thickness of the Bt and Btg horizons is 20 to 43 inches.)
Cg--54 to 72 inches; gray (10YR 6/1) silt loam; massive; friable; few fine roots; many fine prominent brown (7.5YR 4/4) masses of iron accumulation in ped interiors; common soft very dark brown iron and manganese accumulations; moderately acid.
TYPE LOCATION: Boone County, Missouri, 990 feet east and 330 feet south of the northwest corner of sec. 33, T. 48 N., R. 13 W.; USGS Huntsdale topographic quadrangle; lat. 38 degrees 54 minutes 30 seconds N. and long. 92 degrees 23 minutes 50 seconds W.
RANGE IN CHARACTERISTICS: Sand content averages less than 10 percent throughout the series control section. Depth to the base of the argillic is 25 to 65 inches.
The Ap horizon has hue of 10YR, value of 4 or 5 and chroma of 2 or 3. Some pedons have an A horizon less than 6 inches thick with color value of 3 or 4 and chroma of 2 or 3. Dry value is 6 or 7. Texture is silt loam or silty clay loam. Reaction is very strongly acid to neutral.
The E horizon has hue of 10YR, value of 4 to 6 and chroma of 2 to 4. It is silt loam or silty clay loam. Reaction is very strongly acid to slightly acid.
The BE horizon has hue of 10YR or 7.5YR, value of 4 or 5 and chroma of 3 or 4. It is silt loam or silty clay loam.
The upper part of the Bt horizon has hue of 10YR or 7.5YR, value of 4 or 5 and chroma of 3 to 6. The lower part of the Bt horizon and Btg horizon has hue of 7.5YR to 2.5Y, value of 4 to 6, and chroma of 1 to 6. Redox depletions or dominant chroma of 2 or less are above a depth of 40 inches. The Bt horizon is silt loam or silty clay loam. Clay maximum commonly is 30 to 35 percent, but can range to 40 percent. Reaction ranges from very strongly acid to slightly acid.
Some pedons have a BC or BCg horizon.
The Cg or C horizon has hue of 10YR or 2.5Y, value of 4 to 6 and chroma of 1 to 4. It is strongly acid to neutral.
COMPETING SERIES: These are the Birkbeck, Cadiz, Campton, Elco, Eleroy, Hedrick, Homen, Inton, Iona, Libre, Mayville, Minnith, Morningsun (T), Redbud, Rocheport, Rockfield, Somonauk, Uniontown, and Zurich soils. Birkbeck, Cadiz, Campton, Elco, Homen, Libre, Mayville, Minnith, Rockfield, Somonauk, and Zurich soils have more than 10 percent sand in some subhorizon in the series control section. Eleroy and Rocheport soils have a lithic or paralithic contact at the base of the series control section. Hedrick soils have a surface layer, 7 to 9 inches thick, that has value and chroma of 3 or less. Inton soils have a matrix with a hue of 2.5Y or 5Y and chroma of 2 or less within 30 inches of the surface. Iona and Uniontown soils are calcareous in the lower part of the series control section. Redbud soils average more than 30 percent clay in the lower part of the series control section.
GEOGRAPHIC SETTING: Winfield soils are on ridgetops, sideslopes, summits, shoulders, and backslopes of hills, and on terrace treads of high stream terraces. These soils formed in loess. Slope gradients are dominantly 2 to 20 percent with an extreme range up to 45 percent. Mean annual temperature ranges from 52 to 57 degrees F., and mean annual precipitation ranges from 32 to 42 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Menfro, Marion and Weller soils. The Winfield series is the moderately well drained soil in a drainage sequence with the well drained Menfro soils and commonly are on lower slopes. The somewhat poorly drained Marion and the moderately well drained Weller soils contain more clay in the series control section and are upslope from the Winfield soils.
DRAINAGE AND PERMEABILITY: Moderately well drained. Runoff potential is low to high. Permeability is moderate. Saturated hydraulic conductivity is moderately high or high (4.0 to 14.11 micrometers/sec). In undisturbed areas there is a perched water table that has an upper limit of 2.0 to 3.5 feet during November to April in most years.
USE AND VEGETATION: Most areas are cleared and used to grow soybeans, small grains, corn, hay, and pasture. Remaining areas are in hardwood forest. Native vegetation is deciduous hardwoods (oak and hickory).
DISTRIBUTION AND EXTENT: Central and eastern Missouri bordering the river hills of the Missouri and Mississippi Rivers. West-central and southwestern Illinois on loess hillls along the Mississipi River. The series is of large extent.
MLRA OFFICE RESPONSIBLE: Indianapolis, Indiana
SERIES ESTABLISHED: St. Charles County, Missouri, 1947.
REMARKS: Diagnostic horizons and features recognized in this series are:
ochric epipedon - the zone from the surface of the soil to a depth of 14 inches (Ap, E, and BE horizons);
argillic horizon - the zone from approximately 14 inches to 54 inches (Bt1, Bt2, Btg1, and Btg2 horizons);
aquic conditions- iron accumulations and depletions at depths of 2 to 3.5 feet.