LOCATION RADFORD IL+IA MN WI

Established Series
Rev. SES-TJE-AAC
02/2011

RADFORD SERIES

The Radford series consists of very deep, somewhat poorly drained, moderately permeable soils on flood plains. These soils formed in recent silt loam alluvium underlain by buried soils. Slope ranges from 0 to 5 percent. Mean annual precipitation is about 864 mm (34 inches), and mean annual temperature is about 10.0 degrees C (50 degrees F).

TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Fluvaquentic Hapludolls

TYPICAL PEDON: Radford silt loam - on a 1 percent slope with an east aspect in a cultivated field at an elevation of 173 meters (567 feet) above mean sea level. (Colors are for moist soil unless otherwise stated.)

Ap--0 to 18 cm (0 to 7 inches); very dark grayish brown (10YR 3/2) silt loam, brown (10YR 5/3) dry; weak medium subangular blocky structure parting to moderate fine and medium granular; friable; few very fine roots; neutral; clear smooth boundary. [15 to 25 cm (6 to 10 inches) thick]

A--18 to 31 cm (7 to 12 inches); very dark grayish brown (10YR 3/2) silt loam, brown (10YR 5/3) dry; weak medium subangular blocky structure; friable; few very fine roots; neutral; clear smooth boundary. [ 5 to 46 cm (2 to 18 inches) thick]

C--31 to 84 cm (12 to 33 inches); dark grayish brown (10YR 4/2) and very dark grayish brown (10YR 3/2) silt loam with common thin grayish brown (10YR 5/2) and brown (10YR 5/3) lenses; massive; friable; few very fine roots; common faint very dark grayish brown (10YR 3/2) organic coatings in worm channels; few fine rounded black (7.5YR 2.5/1) weakly cemented manganese oxide concretions with diffuse boundaries throughout; neutral; clear smooth boundary. [15 to 64 cm (6 to 25 inches) thick]

Ab1--84 to 107 cm (33 to 42 inches); very dark gray (10YR 3/1) silt loam; weak fine subangular blocky structure parting to moderate medium granular; friable; few very fine roots; few fine rounded black (7.5YR 2.5/1) weakly cemented manganese oxide concretions with diffuse boundaries lining root channels and pores; few fine prominent strong brown (7.5YR 5/8) masses of oxidized iron in the matrix; slightly alkaline; gradual smooth boundary.

Ab2--107 to 183 cm (42 to 72 inches); very dark gray (10YR 3/1) silt loam; moderate fine subangular blocky structure; friable; few very fine roots; few distinct gray (10YR 6/1) dry, clay depletions on faces of peds; few fine rounded black (7.5YR 2.5/1) weakly cemented manganese oxide concretions with diffuse boundaries lining root channels and pores; few fine prominent strong brown (7.5YR 5/8) masses of oxidized iron in the matrix; slightly alkaline; clear smooth boundary. [The combined thickness of the Ab and/or Abb horizons is 13 to 122 cm (5 to 48 inches).]

Bgb--183 to 203 cm (72 to 80 inches); grayish brown (10YR 5/2) silt loam; moderate medium prismatic structure parting to weak medium subangular blocky; friable; few very fine roots; common distinct very dark gray (10YR 3/1) organic coatings lining root channels and pores; slightly alkaline.

TYPE LOCATION: Cass County, Illinois; about 2 1/2 miles north and 2 miles east of Philadelphia; 1,470 feet north and 60 feet east of the center of sec. 2, T. 17 N., R. 9 W.; USGS Ashland topographic quadrangle; lat. 39 degrees 56 minutes 26 seconds N. and long. 90 degrees 04 minutes 43 seconds W.; NAD 27.

RANGE IN CHARACTERISTICS:
Thickness of the mollic epipedon: 25 to 51 cm (10 to 20 inches), but ranges to 25 to 61 cm (10 to 24 inches)
Depth to the base of soil development: 25 to 51 cm (10 to 20 inches), but ranges to 25 to 61 cm (10 to 24 inches)
Depth to the top of the buried soil: 51 to 102 cm (20 to 40 inches)
Depth to carbonates: within a depth of 152 cm (60 inches) in subhorizons of some pedons

Ap and A horizons:
Hue: 10YR
Value: 2 or 3
Chroma: 1 or 2
Texture: silt loam
Reaction: moderately acid to slightly alkaline

C horizon:
Hue: 10YR
Value: 2 to 6
Chroma: typically 1 or 2, it commonly has thin strata with chroma of 3 or 4.
Texture: silt loam but can include thin strata of silty clay loam.
Average clay content: 18 to 27 percent
Average sand content: less than 20 percent
Reaction: slightly acid to slightly alkaline

Ab and/or ABb horizon(s):
Hue: 10YR or N (neutral)
Value: 2 or 3
Chroma: 0 or 1
Texture: silty clay loam, silt loam, clay loam or loam
Average clay content: 24 to 35 percent
Average sand content: 5 to 20 percent
Reaction: slightly acid to slightly alkaline

Bgb horizon (where present):
Hue: 10YR, 2.5Y, 5Y or N (neutral)
Value: 3 to 6
Chroma: 0 to 2
Texture: silt loam

COMPETING SERIES: These are the Fatima, Gilliam, and Tice series. Fatima and Tice soils are more than 24 inches to the base of soil development and do not have a buried soil within a depth of 40 inches. Gilliam soils are calcareous throughout.

GEOGRAPHIC SETTING: Radford soils are on flood plains or toe slopes. Slope ranges from 0 to 5 percent. These soils formed in dark colored, silt loam alluvium 20 to 40 inches thick underlain by buried, dark colored soils formed in older alluvium. Mean annual temperature ranges from 45 to 57 degrees F, and mean annual precipitation varies from 30 to 45 inches.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Arenzville, Huntsville, Lawson, Littleton, Raddle, and Worthen soils. Arenzville, Huntsville, and Lawson soils are in similar positions on the flood plain nearby. Littleton, Raddle, and Worthen soils are in positions upslope from Radford soils on terraces or foot slopes. Arenzville soils do not have a mollic epipedon and Huntsville, Littleton and Worthen soils have a mollic epipedon more than 24 inches thick.

DRAINAGE AND PERMEABILITY: Somewhat poorly drained. These soils have an apparent seasonal high water table at a depth of 1 to 2 feet below the surface at some time between January and May in most years. The potential for surface runoff is negligible to low. Permeability is moderate. Flooding from stream overflow is rare to common for brief periods between November and June.

USE AND VEGETATION: Most areas of Radford soils are cultivated. Corn and soybeans are the principal crops. Some areas are used for pasture. Native vegetation is prairie grasses.

DISTRIBUTION AND EXTENT: Illinois, Iowa, Minnesota, and Wisconsin. The soils of this series are extensive (about 200,000 acres correlated) in MLRAs 95B, 104, 105, 107, 108, 109, and 115.

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

SERIES ESTABLISHED: Christian County, Illinois, 1947.

REMARKS: Diagnostic horizons and features recognized in this pedon are: mollic epipedon - the zone from the surface of the soil to a depth of 12 inches (Ap and A horizons); aquic conditions - redoximorphic features in C horizon and chroma of 2 or less and redox concentrations in the Ab1 and Ab2 horizons: buried soil - the zone from 33 inches to greater than 60 inches.

National Cooperative Soil Survey
U.S.A.