For example, geographer and ethnologist Henry Schoolcraft in the mid-1800s wrote about depressions in the ground on the shore of a lake with wild rice growing in the water. He wrote that wild rice processors placed animal hides in the holes, filled them with rice and stomped on the rice to thresh it. These jigging pits are part of the husking needed to process wild rice, and archaeologists see these holes in the soil stratigraphy in archaeological excavations today. Such historical records from the post-contact period in the Lake Superior region focus on Anishinaabe harvesting and processing techniques. Archaeological investigations of wild rice processing from the American era, before and after the creation of federal Indian reservations, also provide information on the loss of traditional harvesting areas, as 1800s fur trader and Indian interpreter Benjamin G. Armstrong wrote about outsiders "who claimed to have acquired title to all the swamps and overflowed lakes on the reservations, depriving the Indians of their rice fields, cranberry marshes and hay meadows". Despite the close association of the Anishinaabe and wild rice today, indigenous use of this food for subsistence also predates their arrival in the Lake Superior region. The Anishinaabe today were part of a larger Algonquian group who left eastern North America on a centuries-long journey to the west along the St. Lawrence River and Great Lakes. The Anishinaabe migration story details a vision to follow a giant clam shell in the sky to a place where the food grows on the water. This journey ended between the late 1400s and early 1600s in the Lake Superior wild rice country when they encountered the plant. Prehistory Archaeological and other scientific investigations have focused on the prehistoric exploitation of wild rice by humans, including: 1) the Anishinaabe, 2) so-called proto-Anishinaabe who may have later transformed into this culture from an earlier form, 3) other indigenous groups who exist today such as the Sioux people, and 4) archaeological-categorized cultures from the Initial and Terminal Woodland periods whose living lineages today are more difficult to identify. A seminal 1969 archaeological study indicated the prehistoric nature of indigenous wild rice harvesting and processing through radiocarbon dating, putting to rest argument made by some European-Americans that wild rice production did not begin until post-contact times. Researchers tested clay linings of thermal features and jigging pits associated with parching and threshing of the plant. But a more precise