LOCATION LISBON IL+INEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Aquic Argiudolls
TYPICAL PEDON: Lisbon silt loam - on a north-northwest-facing convex slope of 1 percent in a cultivated field at an elevation of 262 meters (858 feet) above mean sea level. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 18 cm (0 to 7 inches); very dark brown (10YR 2/2) silt loam, dark grayish brown (10YR 4/2) dry; moderate fine granular structure, friable; slightly acid; abrupt smooth boundary.
A--18 to 28 cm (7 to 11 inches); very dark brown (10YR 2/2) silt loam, dark grayish brown (10YR 4/2) dry; moderate medium granular structure; friable; neutral; clear smooth boundary. [Combined thickness of the A horizon is 25 to 51 cm (10 to 20 inches).]
BA--28 to 43 cm (11 to 17 inches); brown (10YR 4/3) silty clay loam; moderate medium subangular blocky structure; friable; common fine faint dark grayish brown (10YR 4/2) and few fine faint grayish brown (10YR 5/2) iron depletions in the matrix; moderately acid; clear smooth boundary. [0 to 18 cm (0 to 7 inches) thick]
Bt1--43 to 58 cm (17 to 23 inches); yellowish brown (10YR 5/4) silty clay loam; moderate medium subangular blocky structure parting to strong fine subangular blocky; friable; common distinct dark grayish brown (10YR 4/2) clay films on faces of peds; few fine distinct yellowish brown (10YR 5/6) masses of oxidized iron in the matrix; few fine distinct grayish brown (10YR 5/2) iron depletions in the matrix; moderately acid; clear smooth boundary.
Bt2--58 to 71 cm (23 to 28 inches); light olive brown (2.5Y 5/6) silty clay loam; strong fine angular blocky structure; firm; common distinct grayish brown (10YR 5/2) clay films on faces of peds; common fine faint yellowish brown (10YR 5/6) masses of oxidized iron in the matrix; few fine prominent grayish brown (2.5Y 5/2) iron depletions in the matrix; neutral; clear smooth boundary.
Bt3--71 to 91 cm (28 to 36 inches); olive brown (2.5Y 4/4) silty clay loam; weak medium prismatic structure parting to strong medium angular and subangular blocky; firm; common distinct grayish brown (10YR 5/2) and few distinct dark grayish brown (10YR 4/2) clay films on faces of peds; many medium distinct grayish brown (10YR 5/2) iron depletions in the matrix; slightly alkaline; clear smooth boundary. [Combined thickness of the Bt horizon is 20 to 64 cm (8 to 25 inches).]
2Bt4--91 to 99 cm (36 to 39 inches); yellowish brown (10YR 5/6) clay loam; weak coarse prismatic structure; firm; common distinct dark grayish brown (10YR 4/2) clay films on vertical faces of peds; few fine black (10YR 2/1) very weakly cemented iron-manganese concretions throughout; few medium distinct light yellowish brown (10YR 6/4) masses of oxidized iron in the matrix; common medium prominent light brownish gray (10YR 6/2) iron depletions in the matrix; 1 percent gravel; slightly effervescent; slightly alkaline; clear smooth boundary. [5 to 30 cm (2 to 12 inches) thick]
2C--99 to 178 cm (39 to 70 inches); light yellowish brown (10YR 6/4) loam; massive; firm; pale brown (10YR 6/3) coatings on vertical faces of joints; few fine black (10YR 2/1) very weakly cemented iron-manganese concretions throughout; few fine distinct brownish yellow (10YR 6/6) masses of oxidized iron in the matrix; common fine prominent greenish gray (5GY 6/1) iron depletions in the matrix; 3 percent gravel; strongly effervescent; moderately alkaline.
TYPE LOCATION: Boone County, Illinois; about 4 km (2.5 miles) east of Herbert; 363 m (1,190 feet) north and 94 m (310 feet) east of the southwest corner of sec. 36, T. 43 N., R. 4 E.; USGS Riley topographic quadrangle; lat. 42 degrees 09 minutes 25 seconds N., and long. 88 degrees 43 minutes and 26 seconds W., NAD 27; UTM Zone 16, 0357574 easting and 4668632 northing, NAD 83.
RANGE IN CHARACTERISTICS: The depth to the base of soil development ranges from 61 to 107 cm (24 to 42 inches). The depth to carbonates and the depth to horizons with greater that 15 percent sand ranges from 51 to 102 cm (20 and 40 inches). The thickness of the mollic epipedon commonly ranges from 25 to 51 cm (10 to 20 inches).
The Ap or A horizon has hue of 10YR, value of 2 or 3, and chroma of 1 to 3. It is silt loam. Reaction ranges from moderately acid to neutral.
Some pedons have an AB horizon instead of a BA horizon.
The Bt or BA horizon has hue of 7.5YR, 10YR, or 2.5Y; value of 4 to 6; and chroma of 2 to 6. Redoximorphic features are commonly present. Texture is silty clay loam or silt loam. Average clay content ranges between 25 and 35 percent. Reaction ranges from moderately acid to slightly alkaline.
The 2Bt or 2BC horizon has hue of 7.5YR, 10YR, or 2.5Y; value of 4 to 6; and chroma of 2 to 6. Redoximorphic features are commonly present. Texture is loam or clay loam. Clay content averages between 20 and 34 percent, and sand content averages between 20 and 45 percent. Reaction ranges from slightly acid to moderately alkaline. The calcium carbonate equivalent ranges from 0 to 20 percent.
The 2C horizon has hue of 7.5YR, 10YR, or 2.5Y; value of 4 to 6; and chroma of 2 to 6. Redoximorphic features are commonly present. Texture is loam or sandy loam. Clay content averages between 15 and 25 percent. Sand content averages between 25 and 55 percent. Reaction is slightly alkaline or moderately alkaline. The calcium carbonate equivalent ranges from 15 to 40 percent.
COMPETING SERIES: These are the Arrowsmith, Bearpen, Brenton, Edwardsville, Elburn, Grundelein, Hacreek, Harco, Higginsville, Keller, Lafayette, Lawndale, Lismod, Loran, Mundelein, Muscatune, Raub, Rooks, Rowley, and Shannondale series. Arrowsmith, Edwardsville, Hacreek, Harco, Higginsville, Muscatune, and Rooks soils average less than 15 percent sand in the lower one-half of the series control section. Bearpen, Brenton, Elburn, Keller, Lafayette, Lawndale, Loran, Raub, Rowley, and Shannondale soils are deeper than 102 cm (40 inches) to carbonates. Grundelein soils average more than 15 percent gravel in the lower part of the series control section. Lismod soils have a bulk density of less than 1.70 g/cm3 in the lower part of the series control section. Mundelein soils have a poorly graded sand fraction in the lower one-half of the series control section.
GEOGRAPHIC SETTING: Lisbon soils are on nearly level to gently sloping till plains. Slope gradients range from 0 to 4 percent. These soils formed in 51 to 102 cm (20 to 40 inches) of loess or other silty material and in the underlying loamy till of Wisconsinan Age. Mean annual air temperature ranges from 7 to 11 degrees C (45 to 52 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 207 to 351 m (679 to 1152 feet) above sea level.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Danabrook, Drummer, Elpaso, Herbert, La Rose, Odell, Parr, and Saybrook soils. The moderately well drained Danabrook, Parr, and Saybrook soils and the well drained La Rose soils are on higher positions on the landform. Danabrook and Saybrook soils form a drainage sequence with Lisbon soils. The poorly drained Drummer and Elpaso soils are on lower positions on the landform. Herbert and Odell soils are on similar landform positions nearby. Herbert soils lack a mollic epipedon. Odell soils formed in a thinner mantle of loess.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Somewhat poorly drained. An intermittent perched water table is at a depth of 30 to 61 cm (1.0 foot to 2.0 feet) below the surface at some time between January and May in most years. The potential for surface runoff is low or medium. Saturated hydraulic conductivity is moderately high or high (4.23 to 14.11 micrometers per second) in the solum and moderately high (1.41 to 4.23 micrometers per second) in the underlying material. Permeability is moderate in the solum and moderately slow in the underlying material.
USE AND VEGETATION: Most areas are cultivated. Corn, soybeans, small grain, and meadow are the principal crops. Native vegetation is tall prairie grasses.
DISTRIBUTION AND EXTENT: Central and northern Illinois. Extent is moderate in MLRAs 95B, 108, and 110; about 24,282 hectares (60,000 acres) have been mapped.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Indianapolis, Indiana
SERIES ESTABLISHED: Boone County, Illinois, 1935.
REMARKS: The type location was moved from DeKalb County, Illinois to Boone County, Illinois in May 1997. A silty clay loam substratum phase is recognized. This soil will be investigated during MLRA update activities. Possibly a new soil series will be established.
Diagnostic horizons and features recognized in this pedon are: mollic epipedon - the zone from the surface to a depth of 28 cm (11 inches) (Ap and A horizons); argillic horizon - the zone from about 43 to 99 cm (17 to 39 inches) (Bt1, Bt2, Bt3, and 2Bt4 horizons); discontinuity at a depth of 91 cm (36 inches) - the contact between the Bt3 and 2Bt4 horizons.