LOCATION WAPSIE IAEstablished Series
TAXONOMIC CLASS: Coarse-loamy over sandy or sandy-skeletal, mixed, superactive, mesic Mollic Hapludalfs
TYPICAL PEDON: Wapsie loam with a slope of less than 1 percent - cultivated. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 8 inches; very dark grayish brown (10YR 3/2) loam, grayish brown (10YR 5/2) dry; weak fine granular structure; friable; medium acid; clear smooth boundary. (6 to 9 inches thick)
E--8 to 13 inches; brown (10YR 4/3) loam with some mixing of dark brown (10YR 3/3), pale brown (10YR 6/3) dry; faces of peds dark brown (10YR 3/3); moderate medium platy structure parting to weak thin platy; friable; very pale brown (10YR 7/3) dry, silt and sand coatings on faces of peds; few fine pores; medium acid; clear wavy boundary. (0 to 6 inches thick)
Bt1--13 to 17 inches; dark yellowish brown (10YR 4/4) loam; faces of most peds dark yellowish brown (10YR 3/4); weak fine subangular blocky structure; friable; few thin discontinuous dark brown (7.5YR 3/2) clay films on faces of peds; few very pale brown (10YR 7/3 dry) silt and sand coatings on faces of peds; few fine pores; medium acid; clear smooth boundary.
Bt2--17 to 27 inches; dark yellowish brown (10YR 4/4) sandy clay loam; faces of peds brown (7.5YR 4/4); weak medium prismatic structure parting to weak medium subangular blocky; friable; few thin discontinuous dark brown (7.5YR 3/2) clay films on prisms and faces of peds; few fine and medium pores; few medium and large pebbles; medium acid; abrupt smooth boundary. (Combined thickness of the Bt horizons is 9 to 18 inches.)
BC1--27 to 29 inches; dark yellowish brown (10YR 4/4) sandy loam; weak coarse subangular blocky structure; friable; medium acid; clear smooth boundary. (2 to 5 inches thick)
2BC2--29 to 38 inches; dark yellowish brown (10YR 4/4) gravelly loamy sand; very weak coarse subangular blocky structure; very friable; strongly acid; gradual smooth boundary. (0 to 10 inches thick)
2C--38 to 60 inches; yellowish brown (10YR 5/6) gravelly sand; single grained; loose; strongly acid.
TYPE LOCATION: Howard County, Iowa; about 1/2 mile west of Lourdes; 1,040 feet north and 225 feet west of the the center of sec. 31, T. 98 N., R. 12 W.
RANGE IN CHARACTERISTICS: Solum thickness typically ranges from 24 to 40 inches with an extreme range of 18 to 44 inches. Thickness of solum may or may not correspond to the depth to gravelly loamy sand, gravelly sand, or sand. Depth to these materials ranges from about 20 to 30 inches with an extreme depth of 36 inches. The solum and 2C horizon are typically medium or strongly acid, but some pedons are less acid below 4 feet.
The A or Ap horizon is typically very dark brown (10YR 2/2) or very dark grayish brown (10YR 3/2) but is black (10YR 2/1) or very dark gray (10YR 3/1) where a thin leaf litter is present. The E horizon has 10YR hue, value of 4 or 5, chroma of 3 or 2 and in some pedons includes some mixing of darker colors.
The E horizon is mixed with the Ap horizon in some cultivated areas. Texture of the A horizon and E horizon is sandy loam, sandy clay loam, loam or silt loam high in sand.
The Bt and BC horizon has 10YR or 7.5YR hue, value of 4 or 5, and chroma of 3 through 8. The BC horizon typically has the higher values and chromas. Clay content of the Bt horizon ranges from about 15 to 22 percent, but the weighted average of the control section to a contrasting layer is less than 18 percent. The Bt horizon averages less than 50 percent fine sand or coarser. Sand size is dominantly medium and coarse with small amounts of gravel. The BC horizon is sandy loam or loam with less than 18 percent clay. The sandy loam portion of the BC horizon that has more than 50 percent fine or coarser sand is less than 5 inches thick.
The 2C horizon typically is yellowish brown (10YR 5/4-5/6) but in some pedons has 7.5YR hue. Texture of the 2BC and 2C horizons are gravelly loamy sand, gravelly sand, or sand with some gravel. The percent by volume of gravel in the coarse underlying material is variable, but some strata have between 20 and 50 percent.
COMPETING SERIES: These are the Hazen series of the same family and the Billett, Bixby, Hayfield, Lamont, Lilah, Pardeeville, Sattre, and Schley soils. Hazen soils are less acid in the lower part of the control section. Billett, Lamont, and Pardeeville soils lack contrasting textures in the lower part of the B and C horizons. In addition, the Lamont soils have a lighter colored A or Ap horizon. Bixby soils have a thinner or lighter colored A horizon, a more distinct E horizon, and more clay in their upper part of the solum. Hayfield and Schley soils have colors with lower chroma and/or mottles in the upper part of the solum and have more clay in the Bt horizon. Lilah soils have coarser textures in the upper part of the solum and a thinner Bt horizon. Sattre soils average more than 18 percent clay in the upper part of the solum.
GEOGRAPHIC SETTING: Wapsie soils are typically on terraces along streams and in outwash areas. Slopes are typically convex with gradients from 1 to 3 percent, but slopes range from 0 to 9 percent. Wapsie soils formed in stratified loamy alluvium about 1 1/2 to 2 1/2 feet thick over leached loamy sand and sand that contains some gravel. The amounts of gravel are variable and sand size is typically medium and coarse. Mean annual temperature is approximately 45 to 52 degrees F, and mean annual precipitation ranges from about 30 to 34 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Bixby, Hayfield, and Sattre soils and the poorly drained Marshan soils. Bixby soils are commonly on more convex and steeper slopes. Hayfield and Marshan soils are typically on less sloping landscape positions. Sattre soils are on similar landscapes as the Wapsie soils. Wapsie soils form a partial biosequence with the Saude soils.
DRAINAGE AND PERMEABILITY: These soils are well drained. Runoff is medium. Permeability is moderate in the upper part of the solum and very rapid in the underlying coarse textured material. These soils are somewhat droughty in most years.
USE AND VEGETATION: Commonly used for cultivated crops. Corn, soybeans, small grains, and legume hay are grown. Native vegetation was deciduous trees and prairie grasses.
DISTRIBUTION AND EXTENT: In northeastern Iowa and possibly in southern Minnesota and part of Illinois. They are of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Indianapolis, Indiana
SERIES ESTABLISHED: Howard County, Iowa, 1969.
REMARKS: This unit has been formerly included in the moderately deep phase of the Sattre series in Iowa. A summary of the laboratory data available in Iowa places material 1 in the coarse-loamy but data center around 18 percent clay, with some averaging just over and some just under.