LOCATION RUSHVILLE          IL+IA  

RUSHVILLE SERIES

The Rushville series consists of very deep, poorly drained and very poorly drained, very slowly permeable soils formed in loess on till plains. Slopes range from 0 to 2 percent. Mean annual temperature is about 52 degrees F, and mean annual precipitation is about 37 inches.

TAXONOMIC CLASS: Fine, smectitic, mesic Typic Albaqualfs

TYPICAL PEDON: Rushville silt loam - on a south-facing slope of less than 1 percent in a cultivated field. (Colors are for moist soil unless otherwise stated.)

Ap--0 to 7 inches; dark grayish brown (10YR 4/2) silt loam, light gray (10YR 7/2) dry; weak thin platy structure parting to moderate fine granular; friable; common fine roots; common patchy prominent irregular gray (10YR 6/1) clay depletions on faces of peds; few fine prominent irregular black (2.5Y 2/1) masses of iron-manganese throughout; neutral; clear smooth boundary. (5 to 7 inches thick)

Eg--7 to 13 inches; grayish brown (10YR 5/2) silt loam, light gray (10YR 7/2) dry; moderate medium subangular blocky structure parting to weak thick platy; friable; common fine roots throughout; common fine constricted tubular pores; many continuous prominent gray (10YR 6/1) clay depletions throughout; common fine distinct irregular yellowish brown (10YR 5/4) masses of iron throughout; many fine prominent irregular black (2.5Y 2/1) iron-manganese throughout; neutral; clear smooth boundary. (4 to 12 inches thick)

Btg1--13 to 21 inches; light brownish gray (10YR 6/2) silty clay; moderate medium prismatic structure parting to moderate fine subangular blocky; friable; common fine and medium roots throughout; common fine and medium continuous tubular pores; many continuous distinct grayish brown (10YR 5/2) clay films on faces of peds; common fine distinct irregular yellowish brown (10YR 5/6) masses of iron throughout; few fine prominent rounded black (2.5Y 2/1) iron-manganese concretions throughout; strongly acid; clear wavy boundary.

Btg2--21 to 26 inches; light brownish gray (10YR 6/2) silty clay loam; moderate medium prismatic structure parting to moderate medium subangular blocky; firm; few fine roots throughout; few fine continuous tubular pores; many continuous distinct grayish brown (10YR 5/2) clay films on faces of peds; common fine distinct irregular yellowish brown (10YR 5/8) masses of iron throughout; few fine prominent irregular black (2.5Y 2/1) masses of iron-manganese throughout; few fine prominent rounded black (2.5Y 2/1) iron-manganese concretions throughout; moderately acid; clear wavy boundary.

Btg3--26 to 32 inches; light brownish gray (10YR 6/2) silty clay loam; moderate medium prismatic structure parting to moderate medium subangular blocky; firm; few fine roots throughout; few fine continuous tubular pores; many discontinuous distinct grayish brown (10YR 5/2) clay films on faces of peds; many discontinuous prominent gray (10YR 6/1) silt coats on vertical faces of peds; few fine prominent irregular black (2.5Y 2/1) masses of iron-manganese throughout; many fine distinct irregular yellowish brown (10YR 5/8) masses of iron throughout; moderately acid; clear wavy boundary.

Btg4--32 to 43 inches; light brownish gray (10YR 6/2) silty clay loam; moderate coarse prismatic structure parting to moderate medium and coarse subangular blocky; firm; few continuous distinct grayish brown (10YR 5/2) clay films lining root channels and/or pores; common medium prominent irregular yellowish brown (10YR 5/8) masses of iron throughout; common fine prominent irregular brownish yellow (10YR 6/8) masses of iron throughout; moderately acid; clear wavy boundary.

Btg5--43 to 50 inches; light brownish gray (10YR 6/2) silty clay loam; weak coarse prismatic structure; firm; few continuous distinct grayish brown (10YR 5/2) clay films lining root channels and/or pores; common medium prominent irregular yellowish brown (10YR 5/8) masses of iron throughout; moderately acid; clear wavy boundary. (The combined thickness of the Btg horizons is 18 to 50 inches.)

Cg1--50 to 74 inches; light brownish gray (10YR 6/2) silt loam; massive; firm; few discontinuous distinct dark grayish brown (10YR 4/2) clay films lining root channels and/or pores; many medium and coarse prominent irregular strong brown (7.5YR 5/8) masses of iron throughout and common medium distinct irregular yellowish brown (10YR 5/4) masses of iron throughout; slightly acid; clear wavy boundary.

Cg2--74 to 85 inches; light brownish gray (10YR 6/2) silt loam; massive; firm; few discontinuous distinct dark grayish brown (10YR 4/2) clay films lining root channels and/or pores; many coarse prominent irregular strong brown (7.5YR 5/8) masses of iron throughout; neutral; clear wavy boundary.

TYPE LOCATION: Adams County, Illinois; about 6 miles south of Camp Point; 2150 feet east and 250 feet south of the northwest corner of sec. 23, T. 1 S., R. 6 W.; USGS Liberty, IL topographic quadrangle; Latitude 39 degrees 58 minutes 28.7 seconds N., and Longitude 91 degrees 3 minutes 36.8 seconds W., NAD 27.

RANGE IN CHARACTERISTICS: The depth to the base of the argillic horizon ranges from 40 to 60 inches. The depth to carbonates is greater than 50 inches. The particle-size control section averages between 35 and 45 percent clay. The maximum clay content in any subhorizon is 48 percent. The particle size-control section averages less than 5 percent sand.

The Ap or A horizon has hue of 10YR, value of 4 or 5, and chroma of 1 or 2. Undisturbed pedons have a thin A horizon with value of 2 to 4, and chroma of 1 or 2. Reaction ranges from very strongly acid to neutral, depending upon liming history.

The Eg or BE horizons has hue of 10YR, value of 5 or 6, and chroma of 1 or 2. It is silt loam or silt. Reaction ranges from very strongly acid to moderately acid when not limed. Pedons that have been limed range to neutral.

Some pedons have a B/E horizon less than 3 inches in thickness immediately below the E horizon.

The Btg or BCg horizon has hue of 10YR, 2.5Y or 5Y, value of 4 to 6, and chroma of 1 or 2. Redoxmorphic features have hue of 10YR, 2.5Y, 5Y or 7.5YR, value of 4 to 6, and chroma of 1 to 8. Clay films have value of 3 to 5, and chroma of 0 to 2. Reaction ranges from very strongly acid to slightly alkaline. The Btg horizon is silty clay loam or silty clay. The BCg horizon (where present) is silty clay loam or silt loam.

The Cg horizon has hue of 10YR, 2.5Y or 5Y, value of 4 to 6, and chroma of 1 or 2. Redoxmorphic features have hue of 10YR, 2.5Y, 5Y or 7.5YR, value of 4 to 6, and chroma of 1 to 8. It commonly is silt loam, but the range includes silty clay loam. Clay content ranges from 20 to 30 percent. Reaction ranges from moderately acid to moderately alkaline.

COMPETING SERIES: These are the Ames, Pierron, Watchung, Wynoose, and Zwingle series.
Ames and Wynoose soils average more than 5 percent sand in the lower part of the series control section.
Pierron soils have a mean annual soil temperature of more than 56 degrees F.
Watchung soils formed in residuum and are less than 40 inches to the base of the argillic horizon.
Zwingle soils average more than 45 percent clay in the particle size control section.

GEOGRAPHIC SETTING: Rushville soils are on nearly level summits or depressions on till plains. Slope gradients typically are less than 1 percent, and range from 0 to 2 percent. These soils formed in more than 60 inches of loess. Mean annual air temperature ranges from 46 to 54 degrees F., mean annual soil temperature ranges from 48 to 56 degrees F., and mean annual precipitation ranges from 29 to 45 inches, frost free days ranges from 160 to 190 days, and elevation ranges from 340 to 1020 feet above mean sea level.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Clarksdale, Clinton, Keomah, and Marine soils. The somewhat poorly drained Marine, Clarksdale, and Keomah soils are on slightly higher and slightly more convex parts of the summits. The moderately well drained Clinton soils are dominantly browner in the lower one-half of the series control section, do not have abrupt textural change in the upper lower one-third of the control section, and are on the crests and side slopes of summits above Rushville soils or on side slopes of drainageways below them.

DRAINAGE AND PERMEABILITY: Poorly drained or very poorly drained. The potential for surface water runoff is low or negligible. Permeability is very slow. The seasonal high water table is above the surface to 1.5 feet below the surface in spring in normal years.

USE AND VEGETATION: Most areas are cultivated. Corn, soybeans, small grain, and meadow are the principal crops. Native vegetation is mixed hardwood forest.

DISTRIBUTION AND EXTENT: West central Illinois and southeastern Iowa in MLRA 115 and 108. Rushville soils are of small extent; about 7,500 acres have been correlated to date.

MLRA OFFICE RESPONSIBLE: Indianapolis, Indiana

SERIES ESTABLISHED: Schuyler County, Illinois, 1930.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
ochric epipedon - the zone from the surfaces of the soil to a depth of approximately 13 inches (Ap and Eg horizons);
albic horizon - the zone from approximately 7 to 13 inches (Eg horizon);
abrupt textural change feature - from the E horizon to the Btg1 horizon;
argillic horizon - the zone from approximately 13 to 50 inches (Btg1, Btg2, Btg3, Btg4 and Btg5 horizons);
aquic moisture regime.

ADDITIONAL DATA: Engineering test data for the typical pedon are published in the Soil Survey of Adams County, Illinois. University of Illinois soils lab data for 10 pedons are on file at the state office.