LOCATION RUARK IL

Established Series
Rev. WDP-JWS-RDC
07/2011

RUARK SERIES

The Ruark series consists of very deep, poorly drained soils formed in loamy sediments. These soils are on outwash plains, terraces, and depressions on uplands. Slope ranges from 0 to 2 percent. Mean annual precipitation is about 1143 mm (45 inches), and mean annual temperature is about 13 degrees C (55 degrees F).

TAXONOMIC CLASS: Fine-loamy, mixed, active, mesic Typic Endoaqualfs

TYPICAL PEDON: Ruark fine sandy loam, on a nearly level slope in a cultivated field on a terrace at an elevation of about 102 meters (334 feet) above mean sea level. (Colors are for moist soil unless otherwise stated.)

Ap--0 to 18 cm (0 to 7 inches); grayish brown (10YR 5/2) fine sandy loam, light gray (10YR 7/2) dry; weak medium granular structure; friable; common fine distinct yellowish brown (10YR 5/4) masses of oxidized iron in the matrix; strongly acid; abrupt smooth boundary. [15 to 23 cm (6 to 9 inches) thick]

Eg--18 to 38 cm (7 to 18 inches); grayish brown (10YR 5/2) fine sandy loam; weak thick platy structure; friable; common medium prominent brownish yellow (10YR 6/6) masses of oxidized iron in the matrix; very strongly acid; clear smooth boundary. [20 to 33 cm (8 to 13 inches) thick]

BEg--38 to 50 cm (18 to 20 inches); gray (10YR 5/1) loam; weak coarse subangular blocky structure; friable; few fine prominent yellowish brown (10YR 5/6) masses of oxidized iron in the matrix; very strongly acid; clear smooth boundary. [5 to 13 cm (2 to 5 inches) thick]

Btg1--50 to 84 cm (20 to 33 inches); gray (10YR 5/1) clay loam; weak medium prismatic structure parting to moderate coarse subangular blocky; friable; common faint dark grayish brown (10YR 4/2) clay films on faces of peds; common medium faint light gray (10YR 7/2) iron depletions and common fine and medium prominent brownish yellow (10YR 6/6) and yellowish brown (10YR 5/8) masses of oxidized iron in the matrix; very strongly acid; gradual smooth boundary.

Btg2--84 to 94 cm (33 to 37 inches); gray (10YR 6/1) sandy clay loam; weak coarse subangular blocky structure; friable; few faint grayish brown (10YR 5/2) clay films on faces of peds; common medium prominent yellowish brown (10YR 5/6 and 10YR 5/8) masses of oxidized iron in the matrix; strongly acid; clear smooth boundary. [Combined thickness of the Btg horizon is 30 to 61 cm (12 to 24 inches) thick.]

Cg1-- 94 to 112 cm (37 to 44 inches); gray (10YR 6/1) loam; massive; friable; common fine prominent yellowish brown (10YR 5/6 and 10YR 5/8) masses of oxidized iron in the matrix; common fine and medium prominent black (2.5Y 2.5/1) iron-manganese concretions and manganese masses; slightly acid; clear smooth boundary. [0 to 38 cm (0 to 15 inches) thick}

Cg2--112 to 152 cm (44 to 80 inches); light brownish gray (10YR 6/2) fine sandy loam; massive; friable; common fine prominent yellowish brown (10YR 5/6) masses of oxidized iron in the matrix; neutral.

TYPE LOCATION: Alexander County, Illinois; about 3/4 mile south of Sandusky; 1,195 feet north and 840 feet west of the southeast corner of sec. 24, T. 15 S., R. 2 W.; USGS Tamms, Illinois topographic quadrangle; lat. 37 degrees 11 minutes 36 seconds N. and long. 89 degrees 16 minutes 26 seconds W.; UTM Zone 16, 298178 easting and 4118726 northing, NAD 83:

RANGE IN CHARACTERISTICS:
Depth to the base of the argillic horizon: 89 to 102 cm (35 to 40 inches) and ranges from 76 to 127 cm (30 to 50 inches)
Particle-size control section: averages 20 to 35 percent clay; greater than 30 percent fine sand or coarser material

A or Ap horizon:
Hue: 10YR
Value: 3 to 5 (6 or 7 dry)
Chroma: 1 or 2
Texture: fine sandy loam, loam, or very fine sandy loam
Reaction: very strongly acid to moderately acid except in areas that have been limed

Eg horizon:
Hue: 10YR or 2.5Y
Value: 5 to 7
Chroma: 1 or 2
Texture: loam, sandy loam, or fine sandy loam
Reaction: very strongly acid to moderately acid

BEg horizon:
Hue: 10YR to 5Y
Value: 4 to 6
Chroma: 1 or 2
Texture: loam, sandy loam, or fine sandy loam
Reaction: very strongly acid to moderately acid

Btg horizon:
Hue: 10YR to 5Y
Value: 4 to 6
Chroma: 1 or 2
Texture: sandy clay loam, clay loam, loam, or sandy loam
Reaction: very strongly acid to moderately acid

Cg horizon:
Hue: 10YR to 5Y
Value: 4 to 6
Chroma: 1 or 2
Texture: sandy loam, fine sandy loam, loam, or sandy clay loam; thin strata of
loamy sand, sand, fine gravel, silt loam, or silty clay loam in some pedons

COMPETING SERIES: There are no other series in the same family.

GEOGRAPHIC SETTING: Ruark soils commonly are on outwash plains and alluvial or eolian terraces, and less commonly in depressions on uplands. Slope ranges from 0 to 2 percent. Ruark soils formed in loamy material. Mean annual precipitation ranges from 889 to 1219 mm (35 to 48 inches). Mean annual air temperature ranges from 10 to 14 degrees C (50 to 57 degrees F).

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Alvin, Orio, and Roby soils. Alvin and Roby soils are higher on the landscape and have less than 18 percent clay in the argillic horizon. Orio soils have a dark surface and are on similar landscape positions.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Poorly drained. Potential for surface runoff is negligible to medium. Saturated hydraulic conductivity is moderately high in the argillic horizon and moderately high or high in the substratum. Permeability is moderate or moderately slow in the argillic horizon and moderately rapid to moderately slow in the substratum.

USE AND VEGETATION: Most areas are cropped to corn, soybeans, small grain, and meadow. Native vegetation is deciduous hardwoods, mainly oak and hickory.

DISTRIBUTION AND EXTENT: MLRAs 110, 114A, 114B, 115A, 115B in Illinois. The series is of small extent.

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

SERIES ESTABLISHED: Lawrence County, Illinois, 1952.

REMARKS: Diagnostic horizons and Features in this pedon are:
Ochric epipedon: from the surface to a depth of 51 cm (20 inches) (Ap, Eg, BEg horizons).
Argillic horizon: from 51 to 94 cm (20 to 37 inches) (Btg1 and Btg2 horizons).
Aquic conditions: less than 2 chroma matrix and redox features in all horizons of the series control section.

National Cooperative Soil Survey
U.S.A.