The University of Minnesota named the group of mounds located in
Otter Tail County as the Morrison mounds. Winchell described the mounds as the
"Red River Mounds". The mounds are currently being preserved by the Minnesota
Historical Society. A. E. Jenks with the assistance of a Minnesota University
party excavated four mounds from June 25 to July 10, 1937 and numbered them 1,
2, 12, and 13.
The University’s survey of Mound No.1 was 33 feet in diameter. The only feature discovered in the mound was a shallow burial pit. On the floor of the pit lay a single primary burial on a gravel floor. The skeleton was of a young adult whose bones were badly disintegrated. No artifacts accompanied the burial and no cultural objects were found in the mound fill.
The diameter of this mound was plotted at 31 feet. Scattered bones and fragments of charcoal were found in the mound fill. A total of five skeletons were found in Mound 2. The bones had not been exposed very long, and several of the bones were still held together in proper anatomical articulation.
Mound No. 12 was measured at 30 feet in diameter. This mound featured three pits. Human bones were discovered in the first pit. The bones were found in a circular portion. There was nearly a complete skeleton of a young child, approximately the age of two or three unearthed in the first pit. The second pit was a single primary burial of a adult male. The bones of this pit was poorly preserved. At the base of the third pit was a small amount of red orchre was scattered, but no bones of any kind.
The mound was staked at 34 feet in diameter. Some animal bones and shell fragments were found that suggests that the mound was constructed over a area of habitation. Also found in Mound No. 13 were lumps of charcoal and 10 skeletons that were poorly preserved. Skull fragments including teeth, parts of two femora, parts of one tibia, one humerus, and one innominate were also present.
The only pottery found were two matching body sherds with very coarse grit temper. They have a smooth, black interior and a smooth exterior of a beige color. The average thickness is 0.8 cm.
The earliest dated Woodland site in Minnesota is a burial mound in the Morrison group approximating to be 800 BC In this period the more important members of the group were given elaborate funerals. The members are buried with quantities of what have been very expensive materials, often brought from far distant places, and placed in mounds of various sizes and shapes.
Lloyd Wilford, Burial Mounds of Central Minnesota, Minnesota Historical Society, Minnesota Prehistoric Archaeology Series, St. Paul, 1969.
Eldon Johnson, The Prehistoric People of Minnesota, Minnesota Historical Society, Minnesota Prehistoric Archaeology Series, St. Paul, 1969.
Michael Scullin, Prehistory of Southern Minnesota, Department of Anthropology, Mankato State University, 1987.