Jokela, William E.Fenster, William E.Overdahl, Curtis J.Simkins, Charles A.Grava, John2014-12-302014-12-301981https://hdl.handle.net/11299/16902232 pages; includes drawing and maps. This archival publication may not reflect current scientific knowledge or recommendations. Current information available from the University of Minnesota Extension: https://www.extension.umn.edu.en-USNewsletter or Bulletin