Lars C. Anderson1, Matthew D. Giovanni1, Walter H. Schacht2, and Larkin A. Powell3. (1) Department of Agronomy & Horticulture and the School of Natural Resources, University of Nebraska-Lincoln, 3341 Holdredge St. #4, Lincoln, NE 68503, (2) Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, NE, (3) School of Natural Resources, University of Nebraska-Lincoln, Lincoln, NE