LOCATION OAKTON IAEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, mesic Aquollic Hapludalfs
TYPICAL PEDON: Oakton loam - on a 1 percent slope in a cultivated field on uplands. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 9 inches; very dark gray (10YR 3/1) loam, dark grayish brown (10YR 4/2) and grayish brown (10YR 5/2) dry; weak very fine granular structure; friable; neutral; abrupt smooth boundary.(6 to 9 inches thick)
EB--9 to 13 inches; dark grayish brown (10YR 4/2) loam; very dark grayish brown (10YR 3/2) coatings on peds; weak medium platy structure parting to weak fine subangular blocky; friable; strongly acid; clear smooth boundary.(0 to 5 inches thick)
Bt1--13 to 18 inches; grayish brown (2.5Y 5/2) and light olive brown (2.5Y 5/4) loam; weak fine subangular blocky structure; friable; few fine dark grayish brown (10YR 4/2) clay films in root channels; strongly acid; gradual smooth boundary.
Bt2--18 to 24 inches; olive brown (2.5Y 4/4) loam; common fine grayish brown (2.5Y 5/2) and few distinct strong brown (7.5YR 5/6) mottles; weak fine subangular blocky structure; friable; few dark grayish brown (10YR 4/2) clay films; strongly acid; gradual smooth boundary.
2Bt3--24 to 29 inches; light olive brown (2.5Y 5/4) sandy loam; few fine distinct strong brown (7.5YR 5/8) and few fine faint light brownish gray (10YR 6/2) mottles; weak fine subangular blocky structure; friable; few dark grayish brown (10YR 4/2) clay films; medium acid; gradual smooth boundary.
2Bt4--29 to 36 inches; light olive brown (2.5Y 5/4) sandy loam; few fine distinct strong brown (7.5YR 5/8) and few fine distinct light grayish brown (10YR 6/2) mottles; weak fine prismatic structure parting to weak fine and medium subangular blocky; very friable; few dark grayish brown (10YR 4/2) clay films; few dark concretions (manganese oxides); medium acid; gradual smooth boundary.
2Bt5--36 to 47 inches; light olive brown (2.5Y 5/4) loamy sand; few medium distinct light grayish brown (10YR 6/2) mottles; weak fine prismatic structure; very friable; few dark grayish brown (10YR 4/2) clay films; common dark concretions (manganese oxides); medium acid; gradual smooth boundary.(combined thickness of the Bt horizons range from 30 to 50 inches)
C--47 to 60 inches; light olive brown (2.5Y 5/4) sand; few fine distinct yellowish brown (10YR 5/6) mottles; weak medium prismatic structure in upper part, to massive in lower part; loose; few dark grayish brown (10YR 4/2) clay films; slightly acid.
TYPE LOCATION: Floyd County, Iowa; about 3 miles northeast of the village of Oakwood; 2,320 feet east and 115 feet south of the northwest corner of Sec. 27, T. 95 N., R. 16 W.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 36 to 60 or more inches. The control section averages between 14 and 18 percent clay.
The Ap or A horizon has value of 2 or 3 and chroma of 1 or 2. It is 6 to 10 inches thick.
The E, Eb, or BE horizon has value of 4 or 5 and chroma of 2 or 3. Platy structure, not always evident, is medium or coarse.
The Bt horizons have hue of 10YR or 2.5Y, value of 4 or 5, and chroma of 2 to 6. Sand size in the Bt horizon dominantly is fine or very fine.
Some pedons have 2BC horizons that are similar to the Bt horizon.
The C horizon is sand or loamy sand.
COMPETING SERIES: These are the Brady, Dixboro, and Wasepi series in the same family. Similar soils are the Bronson, Matherton, Poseyville, and Ulster series. Brady soils contain up to 25 percent by volume of coarse fragments throughout the control section. Dixboro soils are underlain at depths less than 40 inches by stratified very fine sand and silt loam and contain free carbonates within depths of 40 inches. Wasepi soils have thinner sola and free carbonates within a depth of 40 inches. Bronson soils have a lighter colored surface layer and do not have low chroma mottles in the upper 4 to 8 inches of the argillic horizon. Matherton soils are fine-loamy. Poseyville soils have thinner sola and calcareous till within a depth of 3 feet. Ulster soils do not have low chroma mottles in the upper part of the argillic horizon.
GEOGRAPHIC SETTING: Oakton soils formed in loamy and sandy eolianand water deposited material on nearly level glaciated uplands. Slope gradients range from 0 to 2 percent. Many areas are downslope from other coarse-loamy soils that occur on low, mound- or dune-like areas. Mean annual temperature ranges from about 44 to 48 degrees F, and mean annual precipitation ranges from about 28 to 34 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bolan, Clyde, Dickinson, Klinger, Maxfield, Oran, and Readlyn soils. Bolan, Dickinson, and Ulster soils typically are upslope from Oakton soils and have better drainage. Bolan and Dickinson soils also have thicker A horizons. Clyde, Klinger, Maxfield, Oran, and Readlyn soils are medium textured, and all except Oran soils have a thicker A horizon. They typically are downslope or adjacent to Oakton soils on the landscape.
DRAINAGE AND PERMEABILITY: Oakton soils are somewhat poorly drained. Surface runoff is slow. Permeability is moderate to moderately rapid in the solum and rapid in the C horizon.
USE AND VEGETATION: Commonly cropped to corn, soybeans, small grain, and grass legume meadows. Native vegetation was oak and hickory trees and prairie grasses.
DISTRIBUTION AND EXTENT: North central Iowa.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Indianapolis, Indiana
SERIES ESTABLISHED: Floyd County, Iowa, 1989. The name is coined from the nearby village of Oakwood.
REMARKS: This series was formerly included in mapping with the Hayfield series.
Diagnostic horizons and features recognized in this pedon are: Ochric epipedon - the zone from the surface to a depth of 13 inches. (Ap and EB horizons) Argillic horizon - the zone from a depth of 13 to 36 inches. (Bt1, Bt2, 2Bt3, and 2Bt4 horizons) Udic moisture regime.