LOCATION MOTTLAND IA+MNEstablished Series
TAXONOMIC CLASS: Coarse-loamy, carbonatic, mesic Entic Hapludolls
TYPICAL PEDON: Mottland loam on a northeast-facing convex slope of 7 percent in a cultivated field. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 7 inches; very dark grayish brown (10YR 3/2) loam, dark grayish brown (10YR 4/2) dry; weak fine granular structure; friable; violent effervescence; moderately alkaline; abrupt smooth boundary. (7 to 9 inches thick)
C1--7 to 11 inches; yellowish brown (10YR 5/6) loam; weak fine subangular structure; friable; soft limestone fragments comprise about 12 percent by volume; violent effervescence; moderately alkaline; clear smooth boundary. (0 to 11 inches thick)
C2--11 to 60 inches; yellowish brown (10YR 5/6) channery fine sandy loam; massive; friable; roots common to 20 inches and few to 48 inches; soft limestone fragments comprise about 20 percent by volume; violent effervescence; moderately alkaline.
TYPE LOCATION: Franklin County, Iowa; about 2 miles west of Sheffield; 1,285 feet north and 140 feet east of the southwest corner of sec. 6, T. 93 N., R. 20 W.
RANGE IN CHARACTERISTICS: The thickness of solum commonly is the same as the thickness of the A horizon. Free carbonates typically are in all horizons, although in some pedons the Ap horizon is leached.
The Ap and A1 horizons are very dark brown (10YR 2/2) or very dark grayish brown (10YR 3/2) unless eroded. They are loam or silt loam. These horizons have up to 10 percent coarse fragments. They typically are moderately alkaline in reaction but range to neutral.
A thin AC horizon is in some pedons. It is very dark grayish brown (10YR 3/2) or dark brown (10YR 3/3) and is loam or silt loam with 5 to 15 percent coarse fragments. The C horizon has 10YR or 2.5Y hue, value of 5 to 7, and chroma of 4 to 8. It is channery and is sandy loam, fine sandy loam, loam, or silt loam.
Typically, 10 to 30 percent of the C horizon consists of soft limestone pebbles, channery fragments or flagstones. Consolidated limestone or shale typically is at depths below 60 inches but is as shallow as 48 inches in a few pedons.
COMPETING SERIES: There are no other series in the same family. Other competing soils are in the Marlean, Rossfield, and Storden series. Marlean soils are loamy-skeletal. Rossfield soils are fine-loamy and formed in 20 to 40 inches of medium textured sediments overlying residuum weathered from arenaceous limestone. Storden soils are fine-loamy and formed in glacial till.
GEOGRAPHIC SETTING: These soils occupy convex slopes with gradients of 2 to 40 percent. They are on gently or moderately sloping ridge crests and gently sloping to very steep sideslopes. They have formed in 7 to 20 inches of loamy sediments overlying residuum weathered from arenaceous limestone. In most places, shale underlies the limestone below a depth of about 4 to 20 feet. Mean annual temperature ranges from about 45 to 49 degrees F, and mean annual precipitation ranges from about 30 to 34 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Rossfield soils and the Jacwin soils. The Rossfield soils are on similar, though usually less sloping, landscape positions. The Jacwin soils generally are lower on the landscape and have IIB horizons formed in shale.
DRAINAGE AND PERMEABILITY: Well drained. Permeability is moderate in the upper 7 to 20 inches and moderately rapid in the substratum. Surface runoff is medium to rapid.
USE AND VEGETATION: The gently sloping and moderately sloping areas are used principally for cultivated crops. Steeper areas usually are left in pasture. Native vegetation was prairie grasses.
DISTRIBUTION AND EXTENT: North-central and northeast Iowa and possibly adjoining states. They are inextensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Indianapolis, Indiana
SERIES ESTABLISHED Franklin County, Iowa, 1977.