Conventional vs. Traited Corn
With commodity prices lower than they have been in the past few years many growers will be looking for ways to cut costs. One way growers may be looking to trim expenses is reducing traits. Is this a smart option? No one can say with 100% certainty that insects will or will not be an issue next year, but there are some trends we can look at.
• If you plant corn after corn the chances for corn rootworm pressure will be higher. Therefore, choosing CRW (Corn rootworm) traited corn may be a good option for you. This is often a good option for silage growers who have more corn/corn rotations.
• For those growers who use an insecticide late on their soybeans, they may kill some of the adult corn rootworms who have adapted the strategy of laying eggs in soybean fields. In this case there may not be as much of an advantage to using a CRW traited corn in Ohio or eastern Indiana.
• European corn borers (ECB) overwinter as larvae in corn residue and emerge in the spring. There are usually 2 generations of ECB per year, with the second generation generally being more damaging than the first. The chart below gives the average percent yield loss from ECB at various growth stages, depending on the number of borers/plant.Note that the chart does not include losses from other issues such as stalk lodging and ear drop.