Bruce Potter, Extension IPM specialist, Ken Ostlie, Bill Hutchison, Extension entomologists, and Angie Peltier, Extension educator Overwintering European corn borer larva and its feeding damage within the lower stalk. While stalk breakage or ear drop are readily visible, the extent of tunneling and physiological yield loss can be seen only after the stalk is split. Photo: Bruce Potter, University of Minnesota. The economics of 2019-2020 corn production has challenged many farmers to minimize production costs. Hybrid selection is one way to reduce costs. Planting corn hybrids without Bacillus thuringiensis (Bt) proteins for protection against European corn borer (ECB), corn rootworm, or both will reduce seed costs. However, if not careful, farmers could inadvertently reduce crop revenues if they select hybrids without considering yield potential or insect populations in their fields. Yield potential is the first thing to consider when selecting a corn hybrid. Bt traits prot