1. Montana State Univ. Central Agricultural Research Center 52583 US HWY 87 Moccasin MT 59462 USA
2. USDA‐ARS Beltsville Agric. Res. Ctr. 10300 Baltimore Ave. Beltsville MD 20705 USA
3. University of Vermont 278 S. Main Street St. Albans VT 05478 USA
4. Dep. of Agronomy and Dep. Horticulture, 106 Horticulture Hall Iowa State Univ. Ames IA 50011 USA
5. Dep. Plant Sci North Dakota State Univ. 166 Loftsgard Hall, North Bolley Drive Fargo ND 58102 USA
6. Dep. Plant Biol., Rutgers The State Univ. NJ 59 Dudley Road ‐ Foran Hall New Brunswick NJ 08901‐8520 USA
7. School of Food and Agric. Univ. Maine 495 College Avenue Orono ME 04473 USA
8. Dep. of Plants, Soils, and Climate Utah State Univ. 4820 Old Main Hall Logan UT 84322–4820 USA
9. Dep. Plant Path Univ. of Wisconsin‐Madison 1630 Linden Dr. Madison WI 53706 USA
10. Dep. of Crop & Soil Sciences North Carolina State Univ. 101 Derieux Place, Campus Box 7620 Raleigh NC 27695 USA