Swanson, Bert T.Calkins, James B.Rudquist, Peter-JonShimek, Steven2019-09-182019-09-18https://hdl.handle.net/11299/2075521 online resource (PDF, 7 pages)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.enReport