1. Virginia Tech, Civil and Environmental Engineering, Blacksburg, Virginia, United States;
2. Oregon State University, 2694, Department of Biological & Ecological Engineering, Corvallis, Oregon, United States;
3. Virginia Tech, Plant Pathology, Physiology, and Weed Science, 403 Latham Hall, Ag Quad Lane, Virginia Tech, Blacksburg, Virginia, United States, 24061-0390;