LOCATION DISCO                   IL

Established Series
Rev. WMT-AAC
01/2011

DISCO SERIES


The Disco series consists of very deep well drained soils formed in wind re-worked loamy and sandy alluvial sediments. Disco soils are on stream and outwash terraces on major drainageways. Slope ranges from 0 to 5 percent. Mean annual precipitation is about 940 mm (37 inches) and mean annual temperature is about 10.6 degrees C (51 degrees F).

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, mesic Pachic Hapludolls

TYPICAL PEDON: Disco sandy loam, on a west facing 1 percent slope at an elevation of 155 meters (510 feet) above mean sea level- cultivated. (Colors are for moist soil unless otherwise stated.)

Ap--0 to 18 cm (0 to 7 inches); very dark grayish brown (10YR 3/2) moist, sandy loam; grayish brown (10YR 5/2) dry; weak medium granular structure; very friable; common very fine roots; moderately acid; abrupt smooth boundary.

A1--18 to 66 cm (7 to 26 inches); very dark brown (10YR 2/2) moist, sandy loam; grayish brown (10YR 5/2) dry; weak fine subangular blocky structure; very friable; moderately few very fine roots; slightly acid; clear smooth boundary.

A2--66 to 86 cm (26 to 34 inches); very dark grayish brown (10YR 3/2) moist, sandy loam; grayish brown (10YR 5/2) dry; weak medium subangular blocky structure; very friable; moderately few very fine roots; moderately acid; clear smooth boundary. [Combined thickness of the A horizon is 25 to 91 cm (10 to 36 inches).]

Bw--86 to 104 cm (34 to 41 inches); brown (10YR 4/3) moist, sandy loam; weak medium subangular blocky structure; friable; moderately few very fine roots; 35 percent (common) faint very dark grayish brown (10YR 3/2), moist, organo-clay films on faces of peds and bridging between sand grains; moderately acid; clear smooth boundary. [Combined thickness of the Bw horizons is 15 to 61 cm (6 to 24 inches).]

C--104 to 203 cm (41 to 80 inches); variegated yellowish brown (10YR 5/6) and dark yellowish brown (10YR 4/6) moist, sand; single grain; loose; moderately acid.

TYPE LOCATION: Tazewell County, Illinois; about 3 miles northwest of Manito; 2,055 feet south and 636 feet west of the center of the section 13, T. 23 N., R. 7 W.; USGS Manito, IL topographic quadrangle; lat. 40 degrees 26 minutes 10.8 seconds N. and long. 89 degrees 50 minutes 23.1 seconds W., NAD 83; UTM Zone 16T, 0259135 easting and 4480062 northing, NAD 83.

RANGE IN CHARACTERISTICS:
Depth to base of soil development: 91 to 183 cm (36 to 72 inches)
Thickness of the mollic epipedon: 61 to 91 cm (24 to 36 inches)
Particle-size control section 25 to 102 cm (10 to 40 inches): averages between 50 and 80 percent fine and coarser sand and averages between 12 and 18 percent clay
Rock fragment content: less than 1 percent

Ap and A horizons:
Hue: 10YR or 7.5YR
Value: 2 to 3
Chroma: 1 to 3
Clay content: 5 to 18 percent
Sand content: 50 to 80 percent
Texture: sandy loam or fine sandy loam
Reaction: strongly acid to slightly acid

Bw horizon:
Hue: 10YR to 5YR
Value: 3 to 5
Chroma: 2 to 6
Clay content: 8 to 22 percent
Sand content: 45 to 85 percent
Texture: loam, sandy loam, fine sandy loam, loamy sand or loamy fine sand
Reaction: moderately acid or strongly acid

BC horizon (where it occurs):
Hue: 10YR to 5YR
Value: 3 to 5
Chroma: 3 to 8
Clay content: 1 to 12 percent
Sand content: 70 to 95 percent
Texture: loamy sand, loamy fine sand, sand or fine sand
Reaction: strongly acid to slightly acid

C horizon:
Hue: 10YR or 7.5YR
Value: 3 to 5
Chroma: 3 to 8
Clay content: 1 to 8 percent
Sand content: 80 to 98 percent
Texture: sand, fine sand, loamy sand or loamy fine sand
Reaction: strongly acid to neutral

COMPETING SERIES: These are the Becker, Carmi, and Flagler series. These series typically contain more than 1 percent gravel in horizons. In addition the Becker soils have a mean annual air temperature of less than 10 degrees C (50 degrees F). Carmi soils have a pH greater than neutral in the C horizon. Flagler soils have a mollic epipedon of less than 61 cm. (24 inches) thick and average 5 to 12 percent clay in the particle-size control section 25 to 102 cm (10 to 40 inches).

GEOGRAPHIC SETTING: Disco soils are on nearly level stream and outwash terraces on major drainageways. Slope ranges from 0 to 5 percent, but is dominantly 0 to 2 percent. Disco soils formed in loamy and sandy alluvial sediments that have been re-deposited by wind. They are not normally subject to flooding. Summers are hot and winters are cold. Mean annual temperature is about 10 to 12.8 degrees C (50 to 55 degrees F), and mean annual precipitation is between 890 and 1016 mm. (35 and 40 inches).

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bloomfield, Dickinson, Onarga, Plainfield, and Sparta soils. These soils are not pachic and are on similar nearby positions. In addition, Onarga soils have argillic horizons, while Bloomfield, Plainfield, and Sparta soils contain more sand in the particle size control section.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained. Saturated hydraulic conductivity is high or very high (14.11 to 141.14 micrometers per second). Permeability is moderately rapid or rapid.

USE AND VEGETATION: Largely cultivated to corn, soybeans, small grain, and hay. Native vegetation is prairie grasses.

DISTRIBUTION AND EXTENT: MLRAs 108B, and 113-- along valleys of major rivers in Illinois. Extent is minor.

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

SERIES ESTABLISHED: Henderson County, Illinois, 1946.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
mollic epipedon - 0 to 86 cm (0 to 34 inches) (Ap, A1, and A2 horizons);
cambic horizon - 86 to 104 cm (34 to 41 inches) (Bw horizon)
A rarely flooded phase is recognized in Clark Co., IL
The type location was moved from Henderson Co., IL to Tazewell Co., IL. Disco is no longer correlated in Henderson Co., IL.

Classification was changed to Pachic (lab data does not fit Cumulic). The Pachic subgroup was added per update to Taxonomy in the Eighth Edition, 1998 Keys to Soil Taxonomy

Additional data: Data from the National Soil Survey Lab and the Pedology Laboratory at the University of Illinois, are on file for several pedons.


National Cooperative Soil Survey
U.S.A.