LOCATION CHENOA IL

Established Series
Rev. SKH-DEC-TJE
02/2017

CHENOA SERIES

The Chenoa series consists of very deep, somewhat poorly drained soils formed in loess or other silty material and the underlying calcareous till. Slope ranges from 0 to 5 percent. Mean annual air temperature is about 10 degrees C (50 degrees F), and mean annual precipitation is about 940 mm (37 inches).

TAXONOMIC CLASS: Fine, illitic, mesic Aquic Argiudolls

TYPICAL PEDON: Chenoa silty clay loam, on a nearly level slope in a cultivated field at an elevation of 211 meters (691 feet) above mean sea level. (Colors are for moist soil unless otherwise stated.)

Ap--0 to 30 cm (0 to 12 inches); black (10YR 2/1) silty clay loam, dark gray (10YR 4/1) dry; moderate fine granular structure; friable; few fine roots; neutral; abrupt smooth boundary. [25 to 38 cm (10 to 15 inches) thick]

BA--30 to 41 cm (12 to 16 inches); brown (10YR 4/3) silty clay loam; weak fine prismatic structure parting to moderate fine angular blocky; friable; few very fine roots; many distinct black (10YR 2/1) organic coatings on faces of peds; few fine faint dark grayish brown (10YR 4/2) iron depletions in the matrix; neutral; clear smooth boundary. [0 to 15 cm (0 to 6 inches) thick]

Bt--41 to 53 cm (16 to 21 inches); brown (10YR 4/3) silty clay loam; moderate fine prismatic structure parting to moderate fine angular blocky; friable; few very fine roots; few distinct very dark grayish brown (10YR 3/2) organo-clay films on faces of peds; common distinct dark grayish brown (10YR 4/2) clay films on faces of peds; few fine distinct gray (10YR 5/1) iron depletions in the matrix; neutral; clear smooth boundary.

Btg1--53 to 66 cm (21 to 26 inches); grayish brown (10YR 5/2) silty clay loam; moderate fine prismatic structure parting to moderate fine angular blocky; friable; few very fine roots; many distinct dark grayish brown (10YR 4/2) clay films on vertical faces of peds; common medium black (10YR 2/1) very weakly cemented iron-manganese concretions throughout; common medium prominent yellowish brown (10YR 5/6) masses of oxidized iron in the matrix; common fine faint gray (10YR 5/1) iron depletions in the matrix; neutral; clear smooth boundary.

Btg2--66 to 81 cm (26 to 32 inches); grayish brown (10YR 5/2) silty clay loam; moderate medium prismatic structure parting to moderate medium angular blocky; friable; few very fine roots; common distinct dark grayish brown (10YR 4/2) clay films on vertical faces of peds; common medium black (10YR 2/1) very weakly cemented iron-manganese concretions throughout; common medium prominent yellowish brown (10YR 5/6) masses of oxidized iron in the matrix; common medium faint gray (10YR 5/1) iron depletions in the matrix; neutral; clear smooth boundary. [Combined thickness of the Bt horizon is 23 to 58 cm (9 to 23 inches).]

2Bt--81 to 91 cm (32 to 36 inches); light olive brown (2.5Y 5/4) silty clay loam; weak medium prismatic structure parting to weak medium angular blocky; firm; few very fine roots; few distinct grayish brown (2.5Y 5/2) clay films on faces of peds; common medium distinct gray (2.5Y 6/1) iron depletions in the matrix; 3 percent gravel; slightly alkaline; clear smooth boundary. [10 to 30 cm (4 to 12 inches) thick]

2C--91 to 152 cm (36 to 60 inches); light olive brown (2.5Y 5/4) silty clay loam; massive; firm; few prominent light brownish gray (10YR 6/2) coatings on vertical cleavage planes; common medium distinct gray (2.5Y 6/1) iron depletions in the matrix; 3 percent gravel; strongly effervescent; moderately alkaline.

TYPE LOCATION: Livingston County, Illinois; about 2.5 miles southeast of Flanagan; 865 feet west and 105 feet south of the northeast corner of sec. 2, T. 27 N., R. 3 E.; USGS Flanagan South topographic quadrangle; lat. 40 degrees 50 minutes 31.1 seconds N. and long. 88 degrees 50 minutes 13.6 seconds W., WGS84; UTM Zone 16, 345124 easting and 4522838 northing, NAD 83.

RANGE IN CHARACTERISTICS:
Depth to the base of the argillic horizon: 64 to 114 cm (25 to 45 inches)
Depth to carbonates: 64 to 114 cm (25 to 45 inches)
Depth to horizons containing gravel and averaging more than 8 percent sand: 51 to 102 cm (20 to 40 inches)
Particle-size control section: averages 35 to 42 percent clay
Sand content in the upper one-half of the series control section: averages 2 to 8 percent

Ap or A horizon:
Hue: 10YR
Value: 2 or 3
Chroma: 1 or 2
Texture: silty clay loam or silt loam
Reaction: moderately acid to neutral

Some pedons have an AB horizon instead of a BA horizon.

Bt horizon:
Hue: 10YR or 2.5Y
Value: 4 to 6
Chroma: 2 to 6
Texture: commonly silty clay loam, but some subhorizons are silty clay
Clay content: 35 to 45 percent
Reaction: moderately acid to neutral

2Bt or 2BC horizon:
Hue: 10YR, 2.5Y or 5Y
Value: 4 to 6
Chroma: 1 to 6
Texture: commonly silty clay loam or silt loam, but some pedons have thin layers of loam or clay loam
Clay content: averages 30 to 40 percent, but individual horizons range to as low as 24 percent
Sand content: averages 5 to 20 percent. The sand fraction is poorly sorted (well graded).
Rock fragment content: averages 1 to 10 percent
Reaction: slightly acid to slightly alkaline in the 2Bt horizon and neutral to moderately alkaline in the 2BC horizon

2C horizon:
Hue: 10YR, 2.5Y or 5Y
Value: 4 to 6
Chroma: 1 to 6
Texture: silty clay loam or silt loam with more than 24 percent clay
Sand content: averages 5 to 20 percent. The sand fraction is poorly sorted (well graded).
Rock fragment content: averages 1 to 10 percent
Reaction: slightly alkaline or moderately alkaline and contains carbonates

COMPETING SERIES: These are the Clarence, Elliott, Martinton and Strole series. Clarence and Strole soils average more than 42 percent clay in the particle-size control section. Elliott soils have horizons containing gravel and more than 8 percent sand within a depth of 51 cm (20 inches). Martinton soils have in the lower part of the series control section subhorizons with more than 20 percent well sorted (poorly graded) sand.

GEOGRAPHIC SETTING: Chenoa soils are on relatively undissected parts of till plains of Wisconsinan Age. Slope gradients range from 0 to 5 percent. The soils formed in 51 to 102 cm (20 to 40 inches) of loess or other silty material and in the underlying calcareous till. Mean annual temperature ranges from 8.9 to 11.7 degrees C (48 to 53 degrees F). Mean annual precipitation ranges from 864 to 1016 mm (34 to 40 inches). Frost-free period is 155 to 190 days. Elevation is 177 to 248 meters (581 to 814 feet) above mean sea level.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Andres, Ashkum, Graymont, Symerton, and Varna soils. Andres soils and the moderately well drained Symerton soils formed in loamy outwash and in the underlying till. The Symerton soils are on higher parts of the landform. The poorly drained Ashkum soils are on adjacent lower lying parts of the landform. The moderately well drained Graymont and Varna soils are on adjacent landform positions and on higher areas. Graymont soils are fine-silty. Varna soils formed in less than 51 cm (20 inches) of loess and in the underlying till.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Somewhat poorly drained. Depth to the top of a perched seasonal high water table ranges from 30 to 61 cm (1 to 2 feet) at some time between January and May in normal years. Potential for surface runoff is low or medium. Saturated hydraulic conductivity is moderately high or high (1.43 to 14.11 micrometers per second) in the solum, and moderately low or moderately high (0.42 to 1.41 micrometers per second) in the till substratum. Permeability is moderate or moderately slow in the solum, and slow in the till substratum.

USE AND VEGETATION: Most areas are cultivated. Corn, soybeans, oats, and meadow are the principal crops. Native vegetation is prairie grass.

DISTRIBUTION AND EXTENT: MLRA 110 and LRU 108A in north-central and east-central Illinois. The series is of moderate extent.

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

SERIES ESTABLISHED: Livingston County, Illinois, 1990.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon: from the surface to a depth of 30 cm (0 to 12 inches) (Ap horizon);.
Argillic horizon: from a depth of 41 to 91 cm (16 to 36 inches) (Bt, Btg1, Btg2, and 2Bt horizons).
Lithologic discontinuity: at a depth of 81 cm (32 inches) (contact between the Btg2 and 2Bt horizons).
Aquic conditions: presence of redox depletions within the argillic horizon.

National Cooperative Soil Survey
U.S.A.