Immer, F. R.Christensen, J. J.Bridgford, R. O.Crim, R. F.2014-12-302014-12-301935-09https://hdl.handle.net/11299/16843415 pages; includes photographs. 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