LOCATION TIMULA                  IL+IA MN MO WI

Established Series
Rev. SLE-JCD
02/2011

TIMULA SERIES

The Timula series consists of very deep well drained soils formed in loess on uplands. Slope ranges from 2 to 60 percent. The mean annual air temperature is about 10.6 degrees C (51 degrees F), and the mean annual precipitation is about 865 mm (34 inches).

TAXONOMIC CLASS: Coarse-silty, mixed, superactive, mesic Typic Eutrudepts

TYPICAL PEDON: Timula silt loam on a northwest-facing 41 percent slope under timber at an elevation of 180 meters (590 feet) above mean sea level, from a Seaton-Timula silt loams, 35 to 60 percent slope map unit. (Colors are for moist soils unless otherwise stated.)

A--0 to 13 cm (0 to 5 inches); dark grayish brown (10YR 4/2) silt loam, light brownish gray (10YR 6/2) dry; weak medium granular structure; friable; many roots; neutral; clear smooth boundary. [8 to 20 cm (3 to 8 inches) thick]

E--13 to 20 cm (5 to 8 inches); brown (10YR 5/3) silt loam; weak medium platy structure; friable; many roots; neutral; clear smooth boundary. [0 to 31 cm (0 to 12 inches) thick]

Bw1--20 to 38 cm (8 to 15 inches); dark yellowish brown (10YR 4/4) silt loam; weak fine and medium subangular blocky structure; friable; common roots; neutral; gradual smooth boundary.

Bw2--38 to 56 cm (15 to 22 inches); yellowish brown (10YR 5/4) silt loam; weak fine and medium subangular blocky structure; friable; few roots; neutral; clear smooth boundary. [Combined thickness of the Bw horizon is 15 to 69 cm (6 to 27 inches).]

C1--56 to 102 cm (22 to 40 inches); light yellowish brown (10YR 6/4) silt; massive; friable; strongly effervescent; moderately alkaline; clear smooth boundary.

C2--102 to 155 cm (40 to 61 inches); pale brown (10YR 6/3) and yellowish brown (10YR 5/6) silt; massive; friable; strongly effervescent; moderately alkaline; clear smooth boundary.

C3--155 to 203 cm (61 to 80 inches); pale brown (10YR 6/3) silt; massive; friable; strongly effervescent; moderately alkaline.

TYPE LOCATION: Henderson County, Illinois; 1,561 feet west and 2,158 feet north of the southeast corner of sec. 10, T. 10 N., R. 5 W.; USGS Oquawka topographic quadrangle; lat. 40 degrees 52 minutes 18 seconds N. and long. 90 degrees 56 minutes 49 seconds W., NAD 83.

RANGE IN CHARACTERISTICS:
Depth to the base of soil sevelopment: 46 to 102 cm (18 to 40 inches)
Depth to carbonates: 46 to 102 cm (18 to 40 inches)
Particle-size control section: coarse silt to fine silt ratio of 1.5:1 or more, and can have as much as 25 percent very fine sand.

Ap or A horizon;
hue: 10YR
Value: 3 or 4
Chroma: 1 to 3
Texture: silt loam or silt
Reaction: slightly acid to slightly alkaline

E horizon:
Hue: 10YR
Value: 4 or 5
Chroma: 2 to 4
Texture: silt loam or silt
Reaction: slightly acid to slightly alkaline
Other features: it has been incorporated into the Ap horizon in some pedons.

An EB horizon is in some pedons.

Bw horizon:
Hue: 10YR
Value: 4 to 6
Chroma: 3 to 6
Texture: silt loam or silt
Reaction: slightly acid to slightly alkaline

Some pedons have a non-Argillic Bt horizon.

BC, Bk, and/or C horizons:
Hue: 0YR, 2.5Y or 5Y
Value: 5 or 6
Chroma: 2 to 6
Texture: silt loam or silt
Reaction: slightly alkaline or moderately alkaline

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

GEOGRAPHIC SETTING: Timula soils are on hill slopes. They formed in coarse loess deposits generally greater than 3 meters (10 feet) thick. Slope gradients range from 2 to 60 percent. The mean annual air temperature ranges from 6.7 to 12.2 degrees C (44 to 54 degrees F), and the mean annual precipitation ranges from 740 to 1070 mm (29 to 42 inches), frost free days range from 140 to 180 days, and elevation ranges from 152 to 415 meters (500 to 1360 feet) above mean sea level.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bold, Hamburg, Seaton, Chute, Fayette, and Mt. Carroll soils. Bold and Hamburg soils are on similar landscapes and have sola less than 46 cm (18 inches) thick. Seaton soils are on slightly higher elevations on similar slopes and on rounded ridge tops and have sola more than 102 cm (40 inches) thick. The Chute soils are sandy and are on similar landscapes. The Fayette and Mt. Carroll soils have argillic horizons and are on similar landscape positions, but also are on rounded and gently sloping ridgetops.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained. The potential for surface runoff is low to high. Saturated hydraulic conductivity is moderately high to high (4.23 to 14.11 micrometers per second). Permeability is moderate. Water table or soil moisture status wet is greater than 183 cm (6 feet) from the surface throughout the year in normal years.

USE AND VEGETATION: The gently sloping to moderately steep areas are used for cultivated crops and pasture. The steep and very steep areas are used for pasture or are wooded. Native vegetation is deciduous forest, mainly oak, hickory, and birch.

DISTRIBUTION AND EXTENT: Western Illinois, eastern Iowa, northwest Missouri, southeastern Minnesota, and southwestern Wisconsin. LRRs K and M, MLRAs 90B, 104, 105, 107B, 108B, and 115C. The series is of large extent (more than 111,000 acres correlated)

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

SERIES ESTABLISHED: Henderson County, Illinois, 1947.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon ? from a depth of 0 to 31 cm (0 to 12 inches) (A and E horizons)
Cambic horizon - from a depth of 20 to 56 cm (8 to 22 inches) (Bw1 and Bw2 horizons).

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National Cooperative Soil Survey
U.S.A.