LOCATION WAUBONSIE          IA+MO NE SD
Established Series
Rev. JRW-BCJ-LEB
02/2003

WAUBONSIE SERIES


The Waubonsie series consists of very deep, moderately well drained soils formed in loamy alluvium and the underlying clayey alluvium on flood plains. Permeability is moderately rapid in the upper part and slow or very slow in the lower clayey part. Slope ranges from 0 to 2 percent. Mean annual air temperature is about 50 degrees F, and mean annual precipitation is about 27 inches.

TAXONOMIC CLASS: Coarse-loamy over clayey, mixed, superactive, mesic Fluventic Hapludolls

TYPICAL PEDON: Waubonsie fine sandy loam with a 1 percent slope - cultivated. (Colors are for moist conditions unless otherwise stated.)

Ap--0 to 7 inches; very dark grayish brown (10YR 3/2) fine sandy loam, grayish brown (10YR 5/2) dry; weak fine granular structure; common fine and medium roots; slightly alkaline; clear smooth boundary.

A1--7 to 12 inches; dark brown (10YR 3/3) and very dark grayish brown (10YR 3/2) fine sandy loam, grayish brown (10YR 5/2) dry; weak fine granular structure; common fine and medium roots; slightly alkaline; clear smooth boundary. (Combined thickness of A horizon is 10 to 12 inches thick)

C--12 to 26 inches; dark grayish brown (10YR 4/2) and grayish brown (10YR 5/2) fine sandy loam; massive; common fine roots in mat at top of horizon; slightly alkaline; abrupt smooth boundary. (10 to 20 inches thick)

2Ab--26 to 37 inches; black (10YR 2/1) silty clay; moderate fine and medium subangular blocky structure; common fine and medium tubular pores; common fine prominent reddish brown (5YR 4/4) and few fine prominent dark brown (7.5YR 3/4) redox concentrations; slightly alkaline; clear smooth boundary. (10 to 20 inches thick)

2Cg1--37 to 58 inches; dark gray (5Y 4/1) and gray (5Y 5/1) silty clay; weak medium prismatic structure parting to weak fine subangular blocky; many fine and medium prominent reddish brown (5YR 4/4) and common fine prominent dark brown (7.5YR 3/4) redox concentrations; very slightly effervescent; slightly alkaline; clear smooth boundary.

2Cg2--58 to 80 inches; dark gray (5Y 4/1) and gray (5Y 5/1) silt loam; massive; many fine and medium prominent dark brown (7.5YR 3/4) and strong brown (7.5YR 4/6) redox concentrations; slightly effervescent; slightly alkaline.

TYPE LOCATION: Fremont County, Iowa; about 1 mile south and 1/4 mile east of the town of Bartlett; 230 feet south and 1240 feet west of the northeast corner of sec. 16, T. 70 N., R. 43 W. U.S.G.S. Topographic Quadrangle; McPaul, Iowa; latitude 40 degrees, 52 minutes and 17 seconds N., longitude 95 degrees, 47 minutes and 46 seconds W.

RANGE IN CHARACTERISTICS: The solum is 10 to 12 inches thick and corresponds to the thickness of the A or Ap horizon. Depth to horizons with clay or silty clay texture ranges from 18 to 30 inches. Waubonsie soils are calcareous and are slightly alkaline or moderately alkaline. Sand content averages less than 15 percent sand in the lower 1/2 of the series control section.

The Ap horizon has hue of 10YR or 2.5Y, value of 3 or 4, and chroma of 2. It is dominantly fine sandy loam but included is very fine sandy loam, silt loam or silty clay loam in some pedons. It contains 12 to 35 percent clay and 15 to 60 percent sand.

The C horizon has hue of 10YR or 2.5Y, value of 4 or 5, and chroma of 2. It is dominantly fine sandy loam or very fine sandy loam, but it contains thin strata or lenses of other textures in some pedons. It contains 12 to 18 percent clay and 45 to 60 percent sand. Redox concentrations are few or common and have hue of 10YR, 7.5YR or 5YR, value of 3 to 6, and chroma from 3 to 8. Redox concentrations with hue of 2.5Y or 5Y and chroma of less than 3 are in the lower 2 to 6 inches of this horizon.

The 2Ab horizon with 2 to 8 percent organic matter is neutral and has hue of 10YR, 2.5Y, or 5Y; value of 3 or less; and chroma of 1 or 2. The 2Cg horizon has hue is 2.5Y or 5Y, value is 4 or 5, and chroma is 1 or 2. Thin, darker-colored strata are present in some pedons. The 2Ab and 2Cg horizons are silty clay or clay with 50 to 60 percent clay and less than 15 percent sand. A loamy substratum phase is recognized. Redox concentrations in this horizon are few to common and have hue of 10YR or 2.5Y.

COMPETING SERIES: There are no other series in this family. Ackmore, Blake, Carr, Haynie, Kenmoor, Modale, and Moville series are similar soils. Ackmore, Blake, Haynie, Modale, and Moville soils all lack fine sandy loam horizons in the upper part of the control section and all of these except Modale and Moville lack horizons with clayey textures in the lower part of the control section. Also, Ackmore soils are noncalcareous. Carr soils lack horizons with clayey texture in the control section. Kenmoor soils are more sandy in the upper part of the control section.

GEOGRAPHIC SETTING: Waubonsie soils are on flood plains within a few miles of or adjacent to the Missouri River channel. Slopes are less than 2 percent. Before the construction of large dams upstream on the Missouri River, they were subject to flooding. Waubonsie soils have formed in recently deposited fine sandy loam alluvial sediments about 2 feet thick and grayish colored silty clay or clay alluvium. The clayey alluvium is 2 to many feet thick. Mean annual air temperature is approximately 45 to 54 degrees F., and mean annual precipitation is approximately 25 to 34 inches. Frost free days range from 145 to 175 days. Elevation ranges from 900 to 1050 feet above mean sea level.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Blake, Haynie, Modale, and Moville soils on similar landscapes and the less sandy Albaton, Grable, Onawa, Owego, and Percival soils on lower elevations. The more sandy Sarpy soils are associates on higher elevations.

DRAINAGE AND PERMEABILITY: Variable but considered moderately well drained. The seasonally high water table is perched at a depth of 1.5 to 2.5 feet in most years. Moderately rapid permeability in the upper part and very slow or slow permeability in the clayey substratum. Runoff is slow. These soils are subject to common flooding for very brief periods and are limited where these soils are protected by dams or levees.

USE AND VEGETATION: Most areas are cultivated. The principal crops are corn, soybeans, small grains, and meadow. Some areas are land-leveled and irrigated.

DISTRIBUTION AND EXTENT: The Missouri River flood plains in Iowa, Missouri, Nebraska, and South Dakota. Waubonsie soils are inextensive.

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

SERIES ESTABLISHED: Woodbury County, Iowa, 1970.

REMARKS: These soils were correlated as Modale soils in previous surveys. This series is not considered to meet the saturation requirements of the Aquent suborder. In previous surveys, this series did not qualify for a mollic epipedon. In recent surveys, this series will meet the requirements for mollic epipedon due to reworking of the surface layer and more active culitivation of this soil. These soils are considered to be partially drained by the down-cutting of streams.

Diagnostic horizons and features recognized in this pedon are: mollic epipedon - zone from the surface to the depth of 12 inches (Ap horizon); udic moisture regime.


National Cooperative Soil Survey
U.S.A.