LOCATION SABLE IL+IA IN WIEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Typic Endoaquolls
TYPICAL PEDON: Sable silty clay loam - nearly level in a cultivated field at an elevation of about 223 meters (732 feet) above mean sea level. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 20 cm (0 to 8 inches); black (10YR 2/1) silty clay loam, dark gray (10YR 4/1) dry; moderate fine and medium granular structure; firm; moderately acid; abrupt smooth boundary.
A--20 to 48 cm (8 to 19 inches); black (10YR 2/1) silty clay loam, dark gray (10YR 4/1) dry; moderate very fine angular blocky structure; firm; few fine rounded dark reddish brown (5YR 3/2) very weakly cemented iron-manganese concretions throughout; slightly acid; clear smooth boundary. [Combined thickness of A horizon ranges from 25 to 51 cm (10 to 20 inches).]
AB--48 to 58 cm (19 to 23 inches); very dark gray (10YR 3/1) silty clay loam, grayish brown (10YR 5/2) dry; moderate fine angular blocky structure; firm; few faint very dark grayish brown (10YR 3/2) organic coatings on faces of peds; few fine rounded dark reddish brown (5YR 3/2) very weakly cemented iron-manganese concretions throughout; slightly acid; clear smooth boundary.[ 0 to 15 cm (0 to 6 inches) thick]
Bg--58 to 74 cm (23 to 29 inches); dark gray (10YR 4/1) silty clay loam; moderate fine and medium subangular blocky structure; firm; common faint very dark gray (10YR 3/1) organic coatings on faces of peds; common fine and medium rounded dark reddish brown (5YR 3/2) very weakly cemented iron-manganese concretions throughout; common medium distinct brown (10YR 5/3) iron-manganese accumulations in the matrix; few medium faint dark grayish brown (10YR 4/2) iron depletions in the matrix; neutral; clear smooth boundary.
Btg1--74 to 97 cm (29 to 38 inches); grayish brown (2.5Y 5/2) silty clay loam; moderate medium and coarse subangular blocky structure; firm; few distinct dark gray (10YR 4/1) clay films on faces of peds; many fine and medium rounded dark reddish brown (5YR 3/2) very weakly cemented iron-manganese concretions throughout; many medium prominent yellowish brown (10YR 5/6) masses of oxidized iron in the matrix; neutral; clear wavy boundary.
Btg2--97 to 119 cm (38 to 47 inches); gray (N 5/0) silt loam; weak medium prismatic structure parting to weak medium and coarse angular blocky; firm; few distinct grayish brown (10YR 5/2) clay films on faces of prisms; common fine rounded dark reddish brown (5YR 3/2) very weakly cemented iron-manganese concretions throughout; many medium prominent yellowish brown (10YR 5/6) masses of oxidized iron in the matrix; slightly alkaline; gradual smooth boundary. [Combined thickness of the B horizon ranges from 33 to 117 cm (13 to 46 inches).]
Cg--119 to 152 cm (47 to 60 inches); gray (N 6/0) silt loam; massive; friable; many medium prominent yellowish brown (10YR 5/6) masses of oxidized iron in the matrix; slightly effervescent; slightly alkaline.
TYPE LOCATION: Warren County, Illinois; about 3 miles northwest of Roseville; 97 feet west and 1,281 feet south of the northeast corner, sec. 14, T. 9 N., R. 3 W.; USGS Kirkwood East topographic quadrangle; lat. 40 degrees, 46 minutes, 22.5 seconds N., long. 90 degrees, 41 minutes, 34.2 seconds W.; UTM Zone 15T 0694708 easting and 4516111 northing, NAD 83.
RANGE IN CHARACTERISTICS: The depth to the base of the cambic horizon ranges from 102 to 152 cm (40 to 60 inches). The thickness of the mollic epipedon ranges from 31 to 61 cm (12 to 24 inches) and extends into the upper part of the B horizon in some pedons. The particle-size control section averages between 27 and 35 percent clay. Average sand content in the series control section is commonly less than 5 percent, but ranges to 8 percent. The depth to carbonates is greater than 102 cm (40 inches). Krotovina are common features in many pedons. Mean annual soil temperature ranges from 9 to 13 degrees C (48 to 56 degrees F).
The Ap or A horizon has hue of 10YR, 2.5Y, 5Y, or is neutral, value of 2 to 3, and chroma of 0 or 1. It commonly is silty clay loam, but in some pedons it is silt loam. Clay content is less than 35 percent. Reaction ranges from moderately acid to neutral.
The AB or BA horizon has hue of 10YR, 2.5Y, 5Y, or is neutral, value of 2 to 3, and chroma of 0 or 1. It is silty clay loam. Reaction ranges from moderately acid to neutral.
The Btg, Bg, BC, or BCg horizon has hue of 10YR, 2.5Y, 5Y, or is neutral, value of 3 to 6, and chroma of 0 to 2. It is silty clay loam in the upper part and silty clay loam or silt loam in the lower part. Clay content ranges from 24 to 35 percent. Reaction is moderately acid to neutral except that the lowest subhorizons in some pedons range to slightly alkaline. The content of total phosphorous has its lowest values in the upper part of the B horizon and is less than 400 ppm.
The Cg horizon has hue of 10YR, 2.5Y, 5Y, or is neutral, value of 3 to 6, and chroma of 0 to 2. It typically is silt loam, but includes silty clay loam in the upper part in some pedons. Clay content ranges from 20 to 28 percent. Reaction ranges from neutral to moderately alkaline. Some pedons do not have carbonates in the upper part of the Cg horizon.
An overwash phase is recognized where recent deposition from adjacent higher parts of the landscape has buried the original A horizon. A stratified substratum phase is also recognized. (see remarks.)
COMPETING SERIES: These are the Chalmers, Chetomba, Dolbee, Drummer, Dunham, Elpaso, Elvira, Garwin, Gillett Grove, Hartsburg, Madelia, Marcus, Mascoutah, Maxcreek, Maxfield, Maxmore, Ossian, Patton, Pella, Rushmore, and Wacousta series. Chalmers soils have less than 20 percent clay in the lower part of the series control section. Chetomba, Drummer, Dunham, Elpaso, Elvira, Gillett Grove, Maxcreek, Maxfield, Maxmore, Pella, and Rushmore soils average more than 8 percent sand in the lower part of the series control section. Dolbee soils formed in alluvium and have a less systematic increase or decrease in silt- and clay-size particles with depth. Garwin soils are higher in total phosphorus and organic phosphorus, contain less clay films and dark coatings on faces of prisms in the lower part of the B horizons, are lower in iron oxides in the lower part of the B and C horizons, and contain more total clay sized particles to a depth of 60 inches. Hartsburg, Madelia, and Wacousta soils have carbonates within a depth of 40 inches. Marcus average more than 35 percent clay in the surface layer. Mascoutah and Patton soils have a mean annual soil temperature of more than 13 degrees C (56 degrees F). Ossian soils have lower clay content in the upper 2 1/2 to 4 feet of the sola, have a less pronounced structural development in the B horizon, and in general have a less systematic increase or decrease in silt- and clay-size particles in the sola.
GEOGRAPHIC SETTING: Sable soils are on level or nearly level summits of loess-covered moraines and stream terraces. Typically, they are on broad interstream divides of till plains, and less commonly on unglaciated hills and on terraces. Slope gradients range from 0 to 2 percent. Sable soils formed entirely in loess. Mean annual temperature ranges from 8 to 13 degrees C (46 to 54 degrees F)., mean annual precipitation ranges from 760 to 1020 mm (30 to 40 inches), frost free days range from 140 to 180 days, and elevation ranges from 104 to 311 meters (340 to 1020 feet) above mean sea level.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Denny, Ipava, Muscatune, Osco, and Tama soils. The poorly drained Denny soils are in shallow closed depressions and have an albic horizon and an argillic horizon. Also, they contain more than 35 percent clay in the particle-size control section. The somewhat poorly drained Ipava and Muscatune soils are commonly on narrow interstream divides, near the edges of broad divides, or on slightly higher or more sloping positions. The moderately well drained Osco soils and well drained Tama soils are on narrow or rounded crests and more sloping parts of the landscape.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Poorly drained. Where drained, the depth to an apparent seasonal high water table is 15 cm (0.5 foot) above the surface to 31 cm (1.0 foot) below the surface at some time between January and May in most years. In the few remaining undisturbed areas, the depth to an apparent seasonal high water table is 15 cm (0.5 foot) above the surface to 15 cm (0.5 foot) below the surface at some time between November and June of most years. The potential for surface runoff is negligible. Saturated hydraulic conductivity is moderately high to high (4.23 to 14.11 micrometers per second). Permeability is moderate.
USE AND VEGETATION: Most areas are used to grow corn and soybeans. Some areas are used to grow small grain and meadow crops. Native vegetation is marsh grasses and sedges.
DISTRIBUTION AND EXTENT: These soils are in Illinois, Wisconsin, Iowa, and Indiana. Sable soils are extensive, over 608,000 acres have been correlated in MLRAs 95B, 104, 105, 108A, 108B, 111A, 111D, and 115C.
MLRA OFFICE RESPONSIBLE: Indianapolis, Indiana
SERIES ESTABLISHED: Livingston County, Illinois, 1938.
REMARKS: The overwash phase and the stratified substratum phase will be evaluated during the update of MLRA 108 to determine where best to correlate these soils.
Additional Data: For lab analysis refer to Soil Survey Nos. S57IL-94-l-(1-8) in SSIR-19. Lab data from the University of Illinois Pedology lab for an additional 35 pedons is available in the state office.
Diagnostic horizons and features recognized in this pedon are:
mollic epipedon -- the zone from the surface to a depth of 23 inches (Ap, A, and AB horizons);
cambic horizon -- the zone from 23 to 47 inches (Bg, Btg1, and Btg2 horizons);
Aquic conditions -- redox concentrations and/or depletions from the surface to a depth of 60 inches (assumed to extend to 80 inches).