LOCATION FLANAGAN IL+IN
Established Series
Rev. JBF-SLE-SEW
06/2015
FLANAGAN SERIES
The Flanagan series consists of very deep, somewhat poorly drained soils that formed in loess or other silty material and the underlying loamy calcareous till on till plains and moraines. Slope ranges from 0 to 7 percent. Mean annual air temperature is 11 degrees C (51 degrees F), and mean annual precipitation is 991 mm (39 inches).
TAXONOMIC CLASS: Fine, smectitic, mesic Aquic Argiudolls
TYPICAL PEDON: Flanagan silt loam - on a 1 percent convex south-facing slope in a grass border of the University of Illinois experimental plots at an elevation of about 223 meters (730 feet) above mean sea level. (Colors are for moist soil unless otherwise stated.)
A1--0 to 20 cm (0 to 8 inches); very dark gray (10YR 3/1) silt loam, gray (10YR 5/1) dry; moderate medium granular structure; friable; slightly acid; gradual smooth boundary.
A2--20 to 38 cm (8 to 15 inches); very dark brown (10YR 2/2) silty clay loam, dark grayish brown (10YR 4/2) dry; moderate medium granular structure; friable; slightly acid; clear smooth boundary.
A3--38 to 46 cm (15 to 18 inches); very dark grayish brown (10YR 3/2) silty clay loam, grayish brown (10YR 5/2) dry; moderate medium granular structure; friable; slightly acid; clear smooth boundary. [Combined thickness of the A horizon is 25 to 50 cm (10 to 20 inches).]
Bt1--46 to 58 cm (18 to 23 inches); dark grayish brown (10YR 4/2) silty clay loam; moderate fine subangular blocky structure; firm; many distinct very dark grayish brown (10YR 3/2) organo-clay films on faces of peds; few fine faint brown (10YR 4/3) iron-manganese accumulations in the matrix; moderately acid; clear smooth boundary.
Bt2--58 to 81 cm (23 to 32 inches); dark grayish brown (10YR 4/2) silty clay loam; moderate medium subangular blocky structure; firm; many distinct very dark grayish brown (10YR 3/2) organo-clay films on faces of peds; common fine faint brown (10YR 5/3) and brown (10YR 4/3) iron-manganese accumulations in the matrix; moderately acid; clear smooth boundary.
Bt3--81 to 97 cm (32 to 38 inches); yellowish brown (10YR 5/4) silty clay loam; moderate medium subangular blocky structure; firm; many distinct very dark grayish brown (10YR 3/2) organo-clay films on faces of peds; common fine faint light yellowish brown (10YR 6/4) and distinct yellowish brown (10YR 5/6) masses of oxidized iron in the matrix; slightly acid; clear smooth boundary.
Bt4--97 to 114 cm (38 to 45 inches); 40 percent yellowish brown (10YR 5/6), 30 percent light brownish gray (10YR 6/2), and 30 percent brown (10YR 5/3) silt loam; weak medium subangular blocky structure; friable; common distinct very dark grayish brown (10YR 3/2) organo-clay films on faces of peds; slightly acid; gradual smooth boundary.[Combined thickness of the Bt horizon is 66 to 102 cm (26 to 40 inches).]
2Bt5--114 to 124 cm (45 to 49 inches); 35 percent yellowish brown (10YR 5/4), 35 percent light olive brown (2.5Y 5/4), and 30 percent light brownish gray (10YR 6/2) silt loam; weak coarse subangular blocky structure; firm; few distinct dark grayish brown (10YR 4/2) clay films on faces of peds; 5 percent fine gravel; neutral; abrupt smooth boundary. [8 to 38 cm (3 to 15 inches) thick]
2C--124 to 152 cm (49 to 60 inches); yellowish brown (10YR 5/4) loam; massive; firm; common medium rounded white (10YR 8/1) weakly cemented calcium carbonate nodules throughout; common fine and medium distinct light brownish gray (10YR 6/2) iron depletions in the matrix; 5 percent fine gravel; slightly effervescent; slightly alkaline.
TYPE LOCATION: Champaign County, Illinois; about 1 mile south of Champaign on University of Illinois south farm; 1,607 feet east and 1,405 feet north of the southwest corner, sec. 19, T. 19 N., R. 9 E.; USGS Urbana topographic quadrangle; lat. 40 degrees, 5 minutes, 14.1 seconds N., and long. 88 degrees, 13 minutes, 57.2 seconds W.; UTM Zone 16T, 0394923 easting and 4438169 northing, NAD 83.
RANGE IN CHARACTERISTICS:
Depth to the base of soil development: 114 to 165 cm (45 to 65 inches)
Depth to horizons with more than 15 percent sand: 102 to 152 cm (40 to 60 inches). Soil development extends into the till.
Depth to carbonates: 114 to 165 cm (45 to 65 inches)
Thickness of the mollic epipedon: 25 to 50 cm (10 to 20 inches). Includes the upper part of the B horizon in some pedons.
Particle-size control section: averages between 35 and 42 percent clay and less than 10 percent fine sand or coarser
Ap and A horizons:
Hue: 10YR
Value: 2 or 3 (4 or 5 dry)
Chroma: 1 or 2
Texture: silt loam or silty clay loam
Clay content: 20 to 32 percent
Reaction: neutral to strongly acid
Some pedons have an AB or 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 or silt loam.
Clay content: 35 to 42 percent in the upper part and 25 to 35 percent in the lower part
Reaction: neutral to moderately acid.
2Bt horizon
Hue: 7.5YR, 10YR, or 2.5Y
Value: 4 to 6
Chroma: 1 to 6. Redoximorphic features are present.
Texture: loam, clay loam, silt loam, or silty clay loam
Clay content: 18 to 30 percent. Individual subhorizons can have up to 40 percent clay.
Sand content: 15 to 40 percent
Gravel content: 1 to 15 percent
Reaction: slightly acid to slightly alkaline. Some pedons contain carbonates in the lower part.
2C horizon
Hue: 7.5YR, 10YR, 2.5Y, or 5Y
Value of 4 to 6
Chroma: 2 to 6
Texture: loam but includes clay loam, silt loam, or silty clay loam
Clay content: 15 to 30 percent
Sand content: 15 to 45 percent
Gravel content: 1 to 15 percent
Reaction: slightly alkaline or moderately alkaline and contains carbonates
COMPETING SERIES: These are the
Biddle,
Herrick,
Ipava,
Macksburg,
Malvern, and
Timewell, soils. Biddle, Herrick, Ipava, Malvern, and Timewell soils average less than 15 percent sand in the lower part of the series control section. Macksburg soils do not have carbonates within a depth of 165 cm (65 inches).
GEOGRAPHIC SETTING: Flanagan soils are on convex slopes of till plains of Wisconsinan Age. Slopes are typically between 0 and 4 percent but range to 7 percent. The soils formed in 102 to 152 cm (40 to 60 inches) of loess and the underlying calcareous till. Mean annual temperature ranges from 8 to 12 degrees C (46 to 54 degrees F); mean annual precipitation ranges from 864 to 1067 mm (34 to 42 inches); frost-free period ranges from 160 to 190 days; and elevation ranges from 174 to 311 meters (570 to 1020 feet) above mean sea level.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Catlin,
Dana,
Drummer,
Milford,
Raub, and
Saybrook soils. The moderately well drained Catlin soils and the poorly drained Drummer soils are on nearby landscapes and form a drainage sequence. The moderately well drained Dana and Saybrook soils and somewhat poorly drained Raub soils are on nearby parts of the till plain where loess is thinner than 102 cm (40 inches). The poorly drained and very poorly drained Milford soils are lower on the landscape in lacustrine areas.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Somewhat poorly drained. A perched seasonal high water table is at a depth of 31 to 61 cm (1 to 2 feet) at some time between January and May in most years. The potential for surface runoff is low to high. Saturated hydraulic conductivity is moderately high (1.41 to 4.23 micrometers per second). Permeability is moderately slow.
USE AND VEGETATION: Most areas of Flanagan soils are used to grow corn and soybeans. Native vegetation is prairie grasses.
DISTRIBUTION AND EXTENT: Flanagan soils are in central and north-central Illinois and in west-central Indiana. The acreage is of large extent (more than 540,000 acres correlated to date) in MLRAs 95B, 108A, 110, and 115C.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Indianapolis, Indiana
SERIES ESTABLISHED: DeWitt County, Illinois, 1937.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
mollic epipedon - the zone from the surface to 46 cm (18 inches) (A1, A2, and A3 horizons);
argillic horizon - the zone from 46 to 97 cm (18 to 38 inches) (Bt1, Bt2, and Bt3 horizons);
lithologic discontinuity - at a depth of 114 cm (45 inches) (contact between the Bt4 and 2Bt5 horizons)
aquic conditions - redoximorphic features in horizons below the mollic epipedon;
udic moisture regime;
mesic temperature regime.
ADDITIONAL DATA: For series typical pedon refer to University of Illinois laboratory samples 17882-17890. Data for 13 additional pedons is in the database of soils sampled by the University of Illinois.
________________________________________
National Cooperative Soil Survey
U.S.A.