LOCATION MILLINGTON IL+IA MN WIEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, calcareous, mesic Cumulic Endoaquolls
TYPICAL PEDON: Millington silt loam - on a slope of less than 1 percent at an elevation of 198 meters (650 feet) above mean sea level. (Colors are for moist soil unless otherwise stated.)
A1--0 to 30 cm (0 to 12 inches); black (10YR 2/1) silt loam, dark gray (10YR 4/1) dry; moderate fine and medium granular structure; friable; common very fine roots; strongly effervescent; moderately alkaline; gradual wavy boundary.
A2--30 to 53 cm (12 to 21 inches); very dark gray (10YR 3/1) silt loam containing about 20 percent sand; gray (10YR 5/1) dry; weak medium subangular blocky structure parting to weak medium granular; friable; common very fine and fine roots; 3 percent snail shells and 5 percent snail-shell fragments; strongly effervescent; moderately alkaline; gradual wavy boundary. [Combined thickness of the A horizon is 30 to 61 cm (12 to 24 inches).]
AB--53 to 66 cm (21 to 26 inches); very dark grayish brown (2.5Y 3/2) silt loam containing about 25 percent sand; grayish brown (2.5Y 5/2) dry; weak fine and medium subangular blocky structure parting to weak fine granular; friable; common very fine roots; few distinct very dark gray (10YR 3/1) organic coatings on surfaces along root channels and pores; 2 percent snail shells and 6 percent snail-shell fragments; strongly effervescent; moderately alkaline; gradual wavy boundary. [0 to 25 cm (0 to 10 inches) thick]
Bg1--66 to 91 cm (26 to 36 inches); dark grayish brown (2.5Y 4/2) loam; weak fine subangular blocky structure; friable; common very fine roots; few distinct very dark grayish brown (2.5Y 3/2) organic coatings on surfaces along root channels and pores; 2 percent snail shells and 4 percent snail-shell fragments; common fine prominent dark yellowish brown (10YR 4/6) iron-manganese concretions throughout; strongly effervescent; moderately alkaline; gradual wavy boundary.
Bg2--91 to 124 cm (36 to 49 inches); dark grayish brown (2.5Y 4/2) stratified silt loam and sandy loam; weak medium subangular blocky structure; friable; common very fine roots; few distinct very dark grayish brown (2.5Y 3/2) organic coatings on surfaces along root channels and pores; 2 percent snail shells and 3 percent snail-shell fragments; many fine faint light brownish gray (2.5Y 6/2) iron depletions in the matrix; strongly effervescent; moderately alkaline; clear wavy boundary. [Combined thickness of the Bg horizon is 41 to 81 cm (16 to 32 inches).]
Cg1--124 to 145 cm (49 to 57 inches); black (2.5Y 2.5/1) stratified silt loam and sandy loam; massive; friable; few very fine roots; 2 percent snail shells and 3 percent snail-shell fragments; few fine distinct light brownish gray (2.5Y 6/2) iron depletions in the matrix; strongly effervescent; moderately alkaline; clear wavy boundary.
Cg2--145 to 157 cm (57 to 62 inches); dark gray (2.5Y 4/1) sandy loam; massive; friable; 14 percent gravel; slightly effervescent; moderately alkaline.
TYPE LOCATION: Kane County, Illinois; 185 meters (608 feet) north and 72 meters (237 feet) east of the southwest corner of sec. 27, T. 39 N., R. 8 E.; USGS Aurora North, IL topographic quadrangle; lat. 41 degrees 49 minutes 37 seconds N. and long. 88 degrees 19 minutes 12 seconds W., NAD 27; UTM Zone 16, 390381 easting and 4631411 northing, NAD 83.
RANGE IN CHARACTERISTICS: The depth to the base of soil development ranges from 61 to 122 cm (24 to 48 inches). The series control section is moderately alkaline or slightly alkaline. Carbonates are in all parts of the fine-earth fraction between 25 and 51 cm (10 and 20 inches). The thickness of the mollic epipedon ranges from 61 to 91 cm (24 to 36 inches).
The A, Ap, or AB horizon has hue of 10YR, 2.5Y, or is neutral, value of 2 to 3, and chroma of 0 to 2. It is loam, silt loam, silty clay loam, or clay loam. Clay content ranges from 20 to 35 percent. Rock fragment content is less than 5 percent.
The Bg horizon has hue of 10YR, 2.5Y, 5Y, or is neutral; value of 2 to 5, and chroma of 0 to 2. It is loam, silt loam, silty clay loam, or clay loam, and in some pedons there are strata of sandy loam and/or thin strata of gravel. Clay content averages between 20 and 35 percent, and rock fragment content averages less than 15 percent.
The Cg horizon has hue of 10YR, 2.5Y, 5Y, or is neutral; value of 2 to 6; and chroma of 0 to 2. Redoximorphic features have chroma ranging to 8. Texture is stratified sandy loam to silty clay loam. Clay content averages between 18 and 35 percent and rock fragment content is less than 15 percent.
COMPETING SERIES: These are the Bishop, Havelock, Riverston, Stearns and Winner series. The Bishop, Stearns, and Winner soils are dry in all parts of the soil moisture control for more than 45 days out of the 120 days following the summer solstice. Also, Stearns soils have SAR greater than 10 in all parts of the series control section. Havelock soils have a mollic epipedon that extends to depths greater than 91 cm (36 inches). Riverston soils average less than 18 percent clay in the lower third of the series control section.
GEOGRAPHIC SETTING: Millington soils are on flood plains. They formed in dark colored, stratified calcareous alluvium derived principally from Mollisols that formed in drift and loess of Wisconsinan Age. Slope gradients are less than 2 percent. Mean annual air temperature ranges from 6 to 12 degrees C (43 to 54 degrees F), mean annual precipitation ranges from 640 to 940 mm (25 to 37 inches), frost-free period ranges from 130 to 180 days, and the elevation ranges from 165 to 457 meters (540 to 1500 feet) above mean sea level.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Du Page, Lawson, and Otter soils. Du Page soils are better drained and are on higher positions. Lawson and Otter soils are noncalcareous and are on similar positions. In addition, they contain less than 15 percent fine or coarser sand in the particle-size control section.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Poorly drained. An intermittent apparent high water table is 15 cm (0.5 foot) above the surface to 46 cm (1.5 feet) below the surface at some time in normal years. The potential for surface runoff is negligible to low. Saturated hydraulic conductivity is moderately high or high (4.23 to 14.11 micrometers/s). Permeability is moderate. This soil is subject to rare to common flooding.
USE AND VEGETATION: Most areas are used for pasture although some areas are cultivated where they are associated with noncalcareous soils and in areas large enough to be economically drained with subsurface drains. Natural vegetation is marsh and wet-prairie grasses.
DISTRIBUTION AND EXTENT: Central and northern Illinois, southern Wisconsin, western Iowa, and southern Minnesota. The extent is moderate in MLRAs 95B, 102A, 102B, 103, 108, and 110.
MLRA OFFICE RESPONSIBLE: Indianapolis, Indiana.
SERIES ESTABLISHED: Kendall County, Illinois, 1941.
REMARKS: Diagnostic horizons and features recognized in this pedon are: mollic epipedon - the zone from the surface to a depth of 66 cm (0 to 26 inches) (A1, A2, and AB horizons); cambic horizon - the zone from 66 to 124 cm (26 to 49 inches) (Bg1 and Bg2 horizons); aquic moisture regime - chroma of 2 or less in the matrix and redoximorphic features in the zone from 66 to 152 cm (26 to 60 inches) (Bg1, Bg2,Cg1, and Cg2 horizons).