LOCATION CLARE IL

Established Series
JAD-KDH-AAC
02/2013

CLARE SERIES

The Clare series consists of very deep, moderately well drained soils formed in loess or other silty material and the underlying loamy stratified outwash on outwash plains, stream terraces, till plains, kames, and eskers. Slope gradients range from 0 to 5 percent. Mean annual precipitation is about 940 mm (37 inches) and mean annual temperature is about 9.4 degrees C (49 degrees F).

TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Oxyaquic Argiudolls

TYPICAL PEDON: Clare silt loam - on a north-facing convex slope of 1 percent in a cultivated field at an elevation of 229 meters (750 feet) above mean sea level. (Colors are for moist soil unless otherwise stated.)

Ap--0 to 13 cm (0 to 5 inches); very dark grayish brown (10YR 3/2) silt loam, grayish brown (10YR 5/2) dry; weak fine granular structure; friable; common very fine roots; neutral; clear smooth boundary.

A--13 to 28 cm (5 to 11 inches); very dark grayish brown (10YR 3/2) silt loam, grayish brown (10YR 5/2) dry; moderate fine and medium subangular blocky structure; friable; common very fine roots; neutral; clear smooth boundary. [Combined thickness for the A horizon ranges from 25 to 51 cm (10 to 20 inches).]

BA--28 to 36 cm (11 to 14 inches); 60 percent dark yellowish brown (10YR 4/4) and 40 percent very dark grayish brown (10YR 3/2) silty clay loam; moderate medium subangular blocky structure; friable; common very fine roots; neutral; gradual wavy boundary.[0 to 20 cm (0 to 8 inches) thick.]

Bt1--36 to 53 cm (14 to 21 inches); dark yellowish brown (10YR 4/4) silty clay loam; weak medium prismatic structure parting to weak fine and medium subangular blocky; friable; common fine roots; common distinct very dark grayish brown (10YR 3/2) organo-clay films on faces of peds and on surfaces along pores: common distinct brown (10YR 4/3) clay films on faces of peds; neutral; gradual wavy boundary.

Bt2--53 to 71 cm (21 to 28 inches); dark yellowish brown (10YR 4/4) silty clay loam; moderate medium prismatic structure parting to moderate fine and medium subangular blocky; firm; common fine roots; common distinct brown (10YR 4/3) clay films on faces of peds and on surfaces along pores; slightly acid; gradual wavy boundary.

Bt3--71 to 81 cm (28 to 32 inches); dark yellowish brown (10YR 4/4) silt loam; moderate medium and coarse subangular blocky structure; friable; few very fine roots; common distinct brown (10YR 4/3) clay films on faces of peds and on surfaces along pores; common fine distinct yellowish brown (10YR 5/6) masses of oxidized iron in the matrix; common medium distinct grayish brown (2.5Y 5/2) iron depletions in the matrix; slightly acid; gradual wavy boundary. [Combined thickness of the Bt horizon ranges from 38 to 76 cm (15 to 30 inches).]

2Bt4--81 to 94 cm (32 to 37 inches); dark yellowish brown (10YR 4/4) loam; moderate medium and coarse subangular blocky structure; friable; few very fine roots; few distinct brown (10YR 4/3) clay films on faces of peds and on surfaces along pores; common medium distinct strong brown (7.5YR 5/6) masses of oxidized iron in the matrix; common medium distinct grayish brown (2.5Y 5/2) iron depletions in the matrix; neutral; clear wavy boundary.

2Bt5--94 to 114 cm (37 to 45 inches); brown (7.5YR 4/4) sandy loam; weak medium and coarse angular blocky structure; friable; few very fine roots; few distinct brown (10YR 4/3) clay films on faces of peds; common medium distinct strong brown (7.5YR 5/6) masses of oxidized iron in the matrix; common medium distinct dark grayish brown (10YR 4/2) iron depletions in the matrix; 2 percent gravel; neutral; gradual wavy boundary.

2Bt6--114 to 155 cm (45 to 61 inches); brown (7.5YR 4/4) clay loam; weak medium and coarse angular blocky structure; friable; few distinct dark brown (7.5YR 3/2) organo-clay films on faces of peds; few distinct brown (10YR 4/3) clay films on faces of peds; common medium rounded black (10YR 2/1) very weakly cemented iron-manganese concretions throughout; common medium rounded yellowish brown (10YR 5/6) very weakly cemented iron-manganese concretions throughout; 5 percent gravel; neutral; clear smooth boundary. [Combined thickness of the 2Bt horizon ranges from 15 to 76 cm (6 to 30 inches).]

2C--155 to 203 cm (61 to 80 inches); brown (7.5YR 5/4) stratified gravelly sandy loam and loam; massive; friable; 17 percent gravel; strongly effervescent; moderately alkaline.

TYPE LOCATION: DeKalb County, Illinois; about 2.4 kilometers (1.5 miles) north of Fairdale; 366 meters (1,200 feet) north and 670 meters (2,200 feet) east of the southwest corner of sec. 7, T. 42 N., R. 3 E.; USGS Cherry Valley topographic quadrangle; lat. 42 degrees 07 minutes 32 seconds N. and long. 88 degrees 55 minutes 51 seconds W., NAD 27; UTM Zone 16T, 340388 easting, 4665526 northing, NAD 83.

RANGE IN CHARACTERISTICS:
Depth to the base of soil development; 102 to 178 cm (40 to 70 inches)
Depth to carbonates: greater than 102 cm (40 inches)
Depth to horizons with greater than 15 percent fine and medium sand: 51 to 102 cm (20 to 40 inches)
Particle-size control section: averages between 25 and 35 percent clay and less than 10 percent fine sand or coarser.

Ap, A, and/or AB horizons:
Hue: 10YR
Value: 2 or 3 (4 or 5 dry)
Chroma: 1 to 3
Texture: typically silt loam, but silty clay loam is also included.
Reaction: moderately acid to slightly alkaline

Bt or BA horizon:
Hue: 10YR or 7.5YR
Value: 3 to 6
Chroma: 3 to 6
Texture: silty clay loam or silt loam
Average clay content: 25 to 35 percent
Reaction: strongly acid to neutral
Redox features: The lower part of the Bt horizon contains redoximorphic features which have chroma of 2 to 8.

2Bt horizon:
Hue: 7.5YR, 10YR or 2.5Y
Value: 4 to 6
Chroma: 3 to 6
Texture: loam, sandy loam, clay loam, silty clay loam, silt loam or sandy clay loam
Gravel content: a few pebbles to 15 percent
Average clay content: 18 to 32 percent
Average fine and medium sand content: 15 to 45 percent. Sand content of individual subhorizons ranges from 10 to 75 percent.
Redox features: Redoximorphic features have chroma of 2 to 8.
Reaction: moderately acid to slightly alkaline
Other features: Some pedons have a subhorizon just above the 2C horizon that is enriched in clay and has darker color value than the subhorizon above it.

2C horizon:
Hue: 7.5YR, 10YR or 2.5Y
Value: 4 to 6
Chroma: 3 to 6
Texture: commonly stratified with dominant textures of sandy loam, loam, or silt loam, and their gravelly analogs with thin strata of loamy sand or sand
Average clay content: 10 to 20 percent
Average sand content: 15 to 75 percent. Sand content of individual subhorizons ranges from 15 to 95 percent.
Rock fragment: 2 to 20 percent gravel
Reaction: slightly acid to moderately alkaline
Redox features: Redoximorphic features have chroma of 2 to 8.
Other features: In some pedons, the 2C horizon is in the lower part of the series control section.

COMPETING SERIES: These are the Assumption, Aviston, Barrington, Blackberry, Buckhart, Catlin, Dana, Danabrook, Geryune, Graymont, Harrison, Keltner, Saybrook, and Totanang series. Assumption, Graymont, and Saybrook soils average more than 20 percent clay in the lower part of the series control section. Aviston, Blackberry, Buckhart, Catlin, and Harrison soils do not have horizons with more than 15 percent sand within a depth of 102 cm (40 inches). Barrington soils have carbonates within a depth of 102 cm (40 inches). Dana, Danabrook, and Geryune soils have a well graded sand fraction in the lower one-half of the series control section. Keltner soils have a paralithic contact within a depth of 152 cm (60 inches). Totanang soils average more than 75 percent sand in the lower part of the series control section.

GEOGRAPHIC SETTING: Clare soils are on loess covered outwash plains, stream terraces, till plains, kames, and eskers of Wisconsinan Age. These soils formed in 51 to 102 cm (20 to 40 inches) of loess or other silty material and in the underlying loamy stratified outwash. Slope gradients range from 0 to 5 percent. Mean annual air temperature ranges from 8 to 12 degrees C (46 to 53 degrees F). Mean annual precipitation ranges from 840 to 1,070 mm (33 to 42 inches). Frost free days range from 150 to 195. Elevation ranges from 154 to 311 meters (505 to 1,020 feet) above sea level.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Barony, Brenton, Drummer, Elburn, Millbrook, and Otter soils. The moderately well drained Barony soils are on similar landform positions adjacent to Clare soils and have a dark colored surface layer less than 10 inches thick. The poorly drained Drummer soils are in slight depressions or lower parts of the landform. The somewhat poorly drained Brenton, Elburn, and Millbrook soils are on slightly lower lying landform positions. The poorly drained Otter soils have a mollic epipedon more than 24 inches thick and are on nearby flood plains.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Moderately well drained. The depth to an apparent seasonal high water table is 61 to 107 cm (2.0 to 3.5 feet) below the surface at some time between February and April in most years. The potential for surface runoff is negligible to low. Saturated hydraulic conductivity is moderately high or high (4.23 to 14.11 micrometers per second) in the upper part of the solum and moderately high or high (4.23 to 42.33 micrometers per second) in the lower part of the solum and in the substratum. Permeability is moderate in the upper part of the solum and moderate or moderately rapid in the lower part of the solum and in the substratum.

USE AND VEGETATION: Most areas are used for cultivated crops. Principal crops are corn, soybeans, small grain, and hay. Some areas are used for pasture. Native vegetation is prairie grasses.

DISTRIBUTION AND EXTENT: Central and northern Illinois. The extent is moderate in MLRAs 95B, 108A, and 108B.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Indianapolis, Indiana.

SERIES ESTABLISHED: DeKalb County, Illinois, 1998. The name Clare is from the town of Clare, in DeKalb County which is near the type location.

REMARKS: This soil was formerly mapped as Proctor in DeKalb County. Through MLRA update activities these soils were found to be moderately well drained instead of well drained and fit an oxyaquic subgroup rather than a typic subgroup.
Diagnostic horizons and features recognized in this pedon are: mollic epipedon - 0 to 28 cm (0 to 11 inches) (Ap and A horizons); argillic horizon - 36 to 155 cm (14 to 61 inches) (Bt1, Bt2, Bt3, 2Bt4, 2Bt5, and 2Bt6 horizons); lithological discontinuity at a depth of 81 cm (32 inches) - the contact between the Bt3 and 2Bt4 horizons; udic moisture regime.

National Cooperative Soil Survey
U.S.A.