Hardman, L. L.Orf, J. H.Rehm, G. W.Stienstra, W. C.2019-09-182019-09-181988https://hdl.handle.net/11299/2074661 online resource (PDF, 4 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