LOCATION CORWIN IN+IL OH

Established Series
Rev. TRZ-TEL-TJE
11/2021

CORWIN SERIES

The Corwin series consists of very deep, moderately well drained soils that are moderately deep to dense till. Corwin soils formed in as much as 46 cm (18 inches) of loess and in the underlying till. They are on till plains and moraines. Slope ranges from 0 to 12 percent. Mean annual precipitation is about 965 mm (38 inches), and mean annual temperature is about 10.6 degrees C (51 degrees F).

TAXONOMIC CLASS: Fine-loamy, mixed, active, mesic Oxyaquic Argiudolls

TYPICAL PEDON: Corwin silt loam, on a convex, 3 percent slope in a cultivated field at an elevation of 255 meters (837 feet) above mean sea level. (Colors are for moist soil unless otherwise stated.)

Ap--0 to 28 cm (11 inches); 75 percent very dark grayish brown (10YR 3/2) silt loam, grayish brown (10YR 5/2) dry, and 25 percent yellowish brown (10YR 5/4) clay loam; moderate medium subangular blocky structure parting to moderate medium granular; friable; many very fine roots; 1 percent gravel; moderately acid; abrupt smooth boundary. [25 to 41 cm (10 to 16 inches) thick]

Bt1--28 to 38 cm (11 to 15 inches); yellowish brown (10YR 5/4) clay loam; moderate medium subangular blocky structure; firm; common very fine roots; few medium tubular pores; common distinct brown (10YR 4/3) clay films on faces of peds; few medium spherical very dark gray (10YR 3/1) worm casts; 8 percent gravel; strongly acid; clear wavy boundary.

Bt2--38 to 56 cm (15 to 22 inches); yellowish brown (10YR 5/4) clay loam; moderate medium subangular blocky structure; firm; common very fine roots; common distinct dark yellowish brown (10YR 4/4) clay films on faces of peds; few medium spherical dark grayish brown (10YR 4/2) worm casts; 9 percent gravel; strongly acid; clear wavy boundary.

Bt3--56 to 66 cm (22 to 26 inches); dark yellowish brown (10YR 4/4) clay loam; moderate medium subangular blocky structure; firm; common very fine roots; common faint brown (10YR 4/3) clay films on faces of peds; few medium spherical dark grayish brown (10YR 4/2) worm casts; few fine distinct yellowish brown (10YR 5/6) masses of oxidized iron in the matrix; 4 percent gravel; slightly acid; clear wavy boundary.

Bt4--66 to 76 cm (26 to 30 inches); brown (10YR 4/3) clay loam; moderate fine subangular blocky structure; firm; common faint dark grayish brown (10YR 4/2) clay films on faces of peds; few medium spherical dark grayish brown (10YR 4/2) worm casts; few medium distinct yellowish brown (10YR 5/6) masses of oxidized iron in the matrix; few medium faint grayish brown (10YR 5/2) iron depletions in the matrix; 4 percent gravel; slightly alkaline; gradual wavy boundary. [Combined thickness of the Bt horizon is 36 to 63 cm (14 to 25 inches).]

Cd1--76 to 102 cm (30 to 40 inches); light olive brown (2.5Y 5/4) loam; weak very coarse prismatic structure; very firm; few prominent white (10YR 8/1) carbonate masses on vertical fracture faces; few medium prominent yellowish brown (10YR 5/8) and few fine prominent red (2.5YR 4/8) masses of oxidized iron in the matrix; few medium distinct light brownish gray (10YR 6/2) iron depletions in the matrix; 7 percent gravel; strongly effervescent; moderately alkaline; gradual wavy boundary. [0 to 38 cm (15 inches) thick]

Cd2--102 to 152 cm (40 to 60 inches); light olive brown (2.5Y 5/4) loam; weak very coarse prismatic structure; very firm; few prominent white (10YR 8/1) carbonate masses on vertical fracture faces; few medium prominent yellowish brown (10YR 5/8) and few fine prominent red (2.5YR 4/8) masses of oxidized iron in the matrix; common medium distinct light brownish gray (10YR 6/2) iron depletions in the matrix; 6 percent gravel; strongly effervescent; moderately alkaline; gradual wavy boundary. [0 to 63 cm (0 to 25 inches) thick]

Cd3--152 to 203 cm (60 to 80 inches); brown (10YR 5/3) loam; massive; very firm; few fine distinct gray (10YR 6/1) iron depletions throughout; 6 percent gravel; strongly effervescent; moderately alkaline.

TYPE LOCATION: Benton County, Indiana; about 3 1/2 miles west of Swanington; 520 feet north and 380 feet west of the southeast corner of sec. 29, T. 25 N., R. 8 W.; USGS Fowler, Ind. topographic quadrangle; lat. 40 degrees 34 minutes 49.7 seconds N. and long. 87 degrees 20 minutes 37.7 seconds W., NAD 27; UTM Zone 16, 470900 easting and 4492247 northing, NAD 83.

RANGE IN CHARACTERISTICS:
Depth to the base of the argillic horizon: 61 to 102 cm (24 to 40 inches)
Depth to 2 chroma iron depletions: 51 to 76 cm (20 to 30 inches)
Depth to densic contact: 61 to 102 cm (24 to 40 inches)

Ap or A horizon:
Hue: 10YR
Value: 2 or 3
Chroma: 1 to 3
Texture: loam or silt loam; clay loam is allowed in severely eroded pedons
Clay content: 15 to 26 percent; 27 to 35 percent in severely eroded pedons
Rock fragment content: 0 to 2 percent; 1 to 5 percent in severely eroded pedons
Reaction: strongly acid to neutral

Bt horizon:
Hue: 7.5YR to 2.5Y
Value: 4 or 5
Chroma: 3 to 6
Texture: loam or clay loam
Clay content: 25 to 35 percent
Sand content: 20 to 45 percent
Rock fragment content: 0 to 10 percent
Reaction: strongly acid to slightly acid in the upper part and moderately acid to slightly alkaline in the lower part

BC, CB, or C horizon, where present:
Hue: 10YR or 2.5Y
Value: 4 or 5
Chroma: 3 to 6
Texture: loam or silt loam
Clay content: 10 to 25 percent
Sand content: 20 to 50 percent
Rock fragment content: 2 to 10 percent
Calcium carbonate equivalent: 5 to 30 percent
Reaction: slightly alkaline or moderately alkaline

Cd horizon:
Hue: 10YR or 2.5Y
Value: 4 or 5
Chroma: 3 to 6
Texture: loam or silt loam
Clay content: 10 to 20 percent
Sand content: 20 to 50 percent
Rock fragment content: 2 to 10 percent
Moist bulk density: 1.75 to 1.95 g/cc
Calcium carbonate equivalent: 20 to 30 percent
Reaction: slightly alkaline or moderately alkaline

COMPETING SERIES: These are the Foresman, Pacer, Parr, Prairieville, and Tippecanoe series. Foresman soils have strata with more than 50 percent sand in the lower part of the series control section. Pacer soils have more than 10 percent rock fragments in the argillic horizon. Parr soils do not have 2 chroma iron depletions within a depth of 76 cm (30 inches). Prairieville soils are deeper than 102 cm (40 inches) to the base of the argillic horizon. Tippecanoe soils have more than 10 percent rock fragments in the lower part of the series control section.

GEOGRAPHIC SETTING: Corwin soils are on swells on till plains and moraines of Wisconsinan age. Slope ranges from 0 to 12 percent. Corwin soils formed in as much as 46 cm (18 inches) of loess and in the underlying loam or silt loam till. Mean annual precipitation ranges from 813 to 1067 mm (32 to 42 inches). Mean annual temperature ranges from 8.9 to 11.7 degrees C (48 to 53 degrees F). Frost-free period is 150 to 180 days. Elevation is 183 to 466 meters (600 to 1,530 feet) above mean sea level.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Chalmers, Montmorenci, Odell, Parr, and Wolcott soils. The poorly drained Chalmers and very poorly drained Wolcott soils are in depressions. The Montmorenci soils are on similar landform positions but have a thinner, dark colored surface layer. The somewhat poorly drained Odell soils are on lower lying swells on till plains. The competing Parr soils are on higher lying swells on till plains.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Moderately well drained. Depth to the top of an intermittent perched high water table ranges from 46 to 76 cm (1.5 to 2.5 feet) during winter and early spring in normal years. Potential for surface runoff is low to high. Saturated hydraulic conductivity is moderately high above the dense till and moderately low or low in the dense till. Permeability is moderate above the dense till and slow or very slow in the dense till.

USE AND VEGETATION: Soils are being used to grow corn, soybeans, and small grain, mainly wheat. Native vegetation is prairie grasses (tall grass prairie).

DISTRIBUTION AND EXTENT: MLRAs 110, 111A, 111C, 111D, and 111E in west-central Indiana, Illinois, and western Ohio. The type location is in MLRA 111D. The series is of moderate extent.

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: AMHERST, MASSACHUSETTS

SERIES ESTABLISHED: Newton County, Indiana, 1948.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon: from the surface to a depth of 28 cm (Ap horizon).
Argillic horizon: from a depth of 28 to 76 cm (Bt horizon).
Densic contact: at 76 cm (top of the Cd1 horizon).
Aquic conditions: redox depletions present in all horizons below a depth of 66 cm.

NASIS Data Mapunit ID 154983 represents a fine sandy loam surface phase on a 0 to 1 percent slope.

ADDITIONAL DATA: Lab characterization data is available for the typical pedon (BE8011, Soil No. S80IN7-11) from the Purdue University Soil Characterization Lab, AES Bulletin No. 412, Vol. 8, Pg. 31. Additional characterization data is available for pedons (BE8013, Soil No. S80IN7-13) and (JR7810, Soil No. S78IN73-10) from the Purdue University Soil Characterization Lab, AES Bulletin No. 412, Vol. 8, Pg. 32, and AES Bulletin No. 274, Vol. 5, Pg. 35, respectively. Transect data is on file at the MLRA Project Office, Plymouth, Indiana.

National Cooperative Soil Survey
U.S.A.