LOCATION AHOLT MO+IL
Established Series
Rev. BJM-KDV
10/2012
AHOLT SERIES
The Aholt series consists of very poorly drained, very slowly permeable soils that formed in thick clayey calcareous alluvium or clayey lacustrine sediments. These soils are on nearly level or slightly depressional low benches and first bottom lands along major rivers and their tributaries and on high benches and glacial lake plains. Mean annual temperature is 54 degrees F, and mean annual precipitation is 37 inches.
TAXONOMIC CLASS: Very-fine, smectitic, calcareous, mesic Vertic Endoaquolls
TYPICAL PEDON: Aholt clay - on a nearly level area in an idle field. (Colors are for moist soil unless otherwise stated).
Ap--0 to 6 inches; black (10YR 2/1) clay, very dark gray (10YR 3/1) dry; strong fine and very fine granular structure; very sticky, very hard; many fine roots; slight effervescence; neutral; clear smooth boundary. (4 to 10 inches thick)
Bg1--6 to 14 inches; black (10YR 2/1) clay, dark gray (N 4/0) dry; few fine distinct brown (10YR 4/3) mottles; strong very fine angular and subangular blocky structure; very sticky, very hard; common fine roots; shiny pressure faces; slight effervescence, mildly alkaline; smooth gradual boundary.
Bg2--14 to 22 inches; very dark gray (10YR 3/1) clay, dark gray (N 4/0) dry; few fine distinct dark grayish brown (2.5Y 4/2) and brown (10YR 4/3) mottles; moderate medium angular and subangular blocky structure; very sticky, very hard; few fine roots; few very fine calcium carbonate concretions; shiny pressure faces; strong effervescence; mildly alkaline; gradual smooth boundary.
Bg3--22 to 34 inches; gray (5Y 5/1) clay, common fine distinct dark grayish brown (2.5Y 4/2) and common fine prominent olive brown (2.5Y 4/4) mottles; moderate medium angular and subangular blocky structure; very sticky, very hard; few fine calcium carbonate concretions; shiny pressure faces; strong effervescence; mildly alkaline; gradual smooth boundary.
Bg4--34 to 46 inches; mixed gray (5Y 5/1) and dark gray (5Y 4/1) clay; common fine prominent olive brown (2.5Y 4/4) mottles; weak coarse subangular blocky structure; very sticky, very hard; few fine calcium carbonate concretions; shiny pressure faces; strong effervescence; mildly alkaline; clear smooth boundary. (Combined thickness of the Bg horizon is 34 to more than 70 inches.)
Cg1--46 to 58 inches; gray (5Y 5/1) and (5Y 6/1) silty clay loam; common medium prominent light olive brown (2.5Y 5/4) mottles; massive; sticky, hard; strong effervescence; mildly alkaline; gradual smooth boundary. Cg2--58 to 66 inches; mottled gray (10YR 5/1) and yellowish brown (10YR 5/6) silty clay loam; massive; sticky, hard; strong effervescence; mildly alkaline.
TYPE LOCATION: Ray County, Missouri; about 2-1/8 miles east of Hardin; 1,980 feet south and 660 feet east of the northwest corner of sec. 35, T. 52 N., R. 26 W.
RANGE IN CHARACTERISTICS: The mollic epipedon is 10 to 24 inches thick. Free carbonates are throughout the control section and reaction ranges from neutral to moderately alkaline.
The Ap horizon has hue of 10YR or 2.5Y; value of 2 or 3, 3 through 5 dry; and chroma of 1 or 2. It is clay or silty clay.
The Bg horizon is neutral or has hue of 2.5Y or 5Y; value of 2 to 6, and chroma of 0 to 2; the darker colors are in the upper part. Some pedons are mottled gray and brown in the lower part. It is clay or silty clay and the control section averages more than 60 percent clay. Distinct or prominent brown and gray mottles occur throughout the soil below the Ap horizons.
The Cg horizon has hue of 2.5Y or 5Y, or is neutral; value of 2 to 6; and chroma of 0 or 2. It is silty clay or silty clay loam and may include thin strata of coarser textures.
COMPETING SERIES: These are the Bosworth,
Kolls, and
Ryepatch series in the same family and the
Booker,
Carlow,
Darwin,
Wabash, and
Waldron series. Bosworth soils are stratified with thin coarser strata and also lack secondary calcium carbonate concretions. Kolls and Ryepatch soils are in areas of lower rainfall. Booker soils lack free carbonates. Carlow, Darwin, and Wabash soils contain less clay and lack free carbonates. Waldron soils contain less clay and generally are stratified below the surface layer.
GEOGRAPHIC SETTING: Aholt soils are on nearly level or slightly depressional low benches and first bottom lands along major rivers and on high benches and glacial lake plains. The slope gradient is 0 to 2 percent. These soils formed in thick clayey calcareous alluvium or clayey lacustrine sediments. The mean annual temperature varies from 52 to 57 degrees F, and mean annual precipitation varies from 32 to 42 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Booker,
Tina,
Wabash, and
Zook soils. Booker soils lack free carbonates and occur on similar landscapes. Tina soils contain less clay and occur on higher bottom positions. Wabash and Zook soils contain less clay and occur on similar landscapes.
DRAINAGE AND PERMEABILITY: Very poorly drained. Permeability is very slow. Runoff is very slow.
USE AND VEGETATION: Soils are cropped to corn, soybeans, and wheat. Native vegetation was willow, cottonwood, and marsh grasses.
DISTRIBUTION AND EXTENT: Missouri and Illinois. Aholt soils are of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Indianapolis, Indiana
SERIES ESTABLISHED: Clay and Ray Counties, Missouri, 1982.
REMARKS: Diagnostic horizons and features recognized in this series are: mollic epipedon-the zone from the surface of the soil to a depth of 22 inches (Ap, Bg1, and Bg2 horizons); cambic horizon-the zone from approximately 22 inches to 46 inches (Bg3 and Bg4 horizons).
National Cooperative Soil Survey
U.S.A.