After 1837, settlers moving into the mid-Mississippi valley eagerly sought the vast timber resources of northern Wisconsin. By 1847, more than thirty saw-mills operated on the Wisconsin, Chippewa, and St. Croix river systems, cutting largely Wisconsin white pine. During the long winter months, logging crews felled and stacked logs on the frozen rivers, and spring thaws flushed the logs down the streams toward the Mississippi River, where they were caught, sorted, scaled, and rafted. Between 1837 and 1901, more than forty million board feet of logs floated down the Great River to saw-mills. The largest log raft on the Mississippi was assembled at Lynxville in 1896; it was 270 feet wide and 1550 feet long and contained two and one-fourth million board feet of lumber. The largest lumber raft on the river originated on Lake St. Croix in 1901; somewhat smaller in size at 270 feet wide and 1450 feet long, it carried more lumber, nine million board feet. The last rafting of lumber on the Mississippi came in 1915, ending a rich, exciting, and colorful era in the history of Wisconsin and the Great River.