LOCATION LA ROSE                 IL

Established Series
Rev. JCD-CCC-AAC
01/2011

LA ROSE SERIES


The La Rose series consists of very deep, well drained soils formed in loamy till on uplands. Slope ranges from 2 to 18 percent. The mean annual temperature is about 8.9 degrees C (48 degrees F), and the mean annual precipitation is about 914 mm (36 inches).

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

TYPICAL PEDON: La Rose silt loam on an eroded, convex, 8 percent slope in a cultivated field at an elevation of 265 meters (870 feet) above mean sea level. (Colors are for moist soil unless otherwise stated.)

Ap--0 to 18 cm (0 to 7 inches); 95 percent very dark grayish brown (10YR 3/2) and 5 percent brown (7.5YR 4/4) silt loam, grayish brown (10YR 5/2) dry; moderate fine granular structure; friable; few fine roots; few rounded gravel; neutral; abrupt smooth boundary. [18 to 30 cm (7 to 12 inches) thick]

Bt1--18 to 36 cm (7 to 14 inches); brown (7.5YR 4/4) clay loam; moderate fine subangular blocky structure; friable; few fine roots; common distinct dark brown (10YR 3/3) organo-clay films on faces of peds; common prominent very dark grayish brown (10YR 3/2) organo-clay films on surfaces along pores and root channels; few rounded gravel; neutral; clear smooth boundary.

Bt2--36 to 48 cm (14 to 19 inches); brown (7.5YR 4/4) clay loam; moderate medium subangular blocky structure; friable; few fine roots; common distinct dark brown (10YR 3/3) organo-clay films on faces on peds; common prominent very dark grayish brown (10YR 3/2) organo-clay films on surfaces along pores and root channels; few rounded gravel; neutral; clear smooth boundary. [Combined thickness of the Bt horizon is 8 to 36 cm (3 to 14 inches).]

C1--48 to 107 cm (19 to 42 inches); brown (7.5YR 5/4) loam; massive; firm; few fine prominent strong brown (7.5YR 5/8) masses of oxidized iron in the matrix; few rounded gravel; strongly effervescent; slightly alkaline; gradual smooth boundary.

C2--107 to 152 cm (42 to 60 inches); brown (7.5YR 5/4) loam; massive; firm; few fine prominent strong brown (7.5YR 5/8) masses of oxidized iron in the matrix; few rounded gravel; violently effervescent; moderately alkaline.

TYPE LOCATION: Lee County, Illinois; about 4 miles northeast of Compton; 2,342 feet north and 114 feet east of the southwest corner of sec. 33, T. 38 N., R. 2 E. USGS Compton quadrangle; lat. 41 degrees 43 minutes 22.6 seconds N. and long. 89 degrees 01 minutes 07 seconds W.; NAD27.

RANGE IN CHARACTERISTICS:
Thickness of the mollic epipedon: typically 18 to 20 cm (7 or 8 inches) and ranges to 31 cm (12 inches)
Depth to the base of the argillic horizon: less than 61 cm (24 inches)
Depth to calcium carbonates: 25 to 61 cm (10 to 24 inches)
Average content of clay in the particle-size control section: between 27 and 35 percent

Ap or A horizon:
Hue: 10YR
Value: 2 or 3
Chroma: 1 to 3
Texture: commonly loam or silt loam, but the range includes clay loam and silty clay loam in severely eroded areas. Reaction: neutral or slightly alkaline.

Some pedons have an AB or BA horizon.

Bt horizon:
Hue: 10YR, 7.5YR or 5YR
Value: 4 or 5
Chroma: 3 or 4
Texture: commonly clay loam and less commonly is silty clay loam
Content of gravels: less than 7 percent
Reaction: slightly acid to slightly alkaline

Some pedons have a BC horizon.

C horizon:
Hue: 7.5YR or 10YR
Value: 4 to 6
Chroma: typically 3 or 4 in the matrix, but ranges from 2 to 8 in redoximorphic features.
Texture: loam or silt loam with a high content of sand.
Content of gravels: less than 10 percent
Reaction: moderately alkaline or slightly alkaline
Calcium carbonate equivalent: 15 to 40 percent

COMPETING SERIES: These are the Hochheim, Lickcreek, Linkville, Markesan, Plattville, Rotamer, Wea, and Wyanet series. All the soils except Hochheim, Markesan, and Rotamer soils have argillic horizons that extend to depths of more than 61 cm (24 inches). Hochheim and Markesan soils have a calcium carbonate equivalent of more than 40 percent in the lower part of the series control section. Rotamer soils average more than 10 percent gravel in the lower part of the series control section.

GEOGRAPHIC SETTING: La Rose soils are on gently sloping to moderately steep morainic areas and dissected Wisconsin till plains. Slope gradients range from 2 to 18 percent. These soils formed in calcareous loam or silt loam till thought to be of Wisconsin age. As much as 25 cm (10 inches) of loess or other silty deposits are on the surface of some pedons. Clay mineralogy of the till predominantly is illitic. The mean annual temperature ranges from 7.8 to 12.2 degrees C (46 to 54 degrees F), mean annual precipitation ranges from 813 to 991 mm (32 to 39 inches), frost free period ranges from 150 to 180 days, and elevation ranges from 207 to 311 meters (680 to 1,020 feet) above mean sea level.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Catlin, Corwin, Flanagan, Hennepin, Octagon, Strawn, and Wyanet soils. The moderately well drained Catlin soils and the somewhat poorly drained Flanagan soils have thicker sola and a thicker mantle of loess, and are on nearby higher-lying or less sloping positions on the till plain. The moderately well drained Corwin and Wyanet soils have thicker sola and are on similar or higher-lying landform positions. Hennepin soils are on similar or steeper slopes nearby and do not have a mollic epipedon or an argillic horizon. Octagon soils do not have a mollic epipedon, have a thicker solum, and are on similar or slightly higher-lying landform positions typically closer to the major streams. Strawn soils do not have a mollic epipedon and are on similar slopes nearby and closer to major streams.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained. The potential for surface runoff is low or medium. Saturated hydraulic conductivity is moderately high to high (4.23 to 14.11 micrometers per second) in the solum and moderately low to moderately high (0.42 to 4.23 micrometers per second) in the substratum. Permeability is moderate in the solum and slow to moderately slow in the substratum.

USE AND VEGETATION: Most areas of these soils are cultivated, but some areas are used for pasture. Corn, soybeans, small grain, and meadow are the principal crops.

DISTRIBUTION AND EXTENT: Northern and eastern Illinois. The extent is moderate in LRRs K and M, MLRAs 95B, 108A, 108B, 110, and 115C.

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

SERIES ESTABLISHED: Marshall County, Illinois, 1934.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
mollic epipedon - from a depth of 0 to 18 cm (0 to 7 inches) (Ap horizon, > 1/3 solum thickness);
argillic horizon - from a depth of 18 to 48 cm (7 to 19 inches) (Bt1 and Bt2 horizons).


National Cooperative Soil Survey
U.S.A.