By Connor Lynch
GUELPH — As Ontario corn starts tasseling, growers need to get out and check the emerging ears for Western Bean Cutworm (WBC) before it chews open the crop.
OMAFRA insect expert Tracey Baute told Farmers Forum that delayed planting this year set up the adult form of the worm, the moth, with the perfect time to lay its eggs on Ontario corn fields.
Although the worms don’t damage yields that much, they feed on the tassels and then the ears of the corn. They then chew on the kernels of corn, which significantly affects quality. Once the ear of the corn is open the corn is exposed to fungus and other diseases.
Baute said farmers should be scouting their crops regularly, as the weird weather this year means that corn can be maturing at different times in the same field. Once the corn has started tasseling is the best time to start checking for eggs or worms. Tasseling on corn in Ontario happens around the end of July to the beginning of August.
Timing will be everything, she said. Guidelines in the United States are to spray for the worm when the corn as a little bit of tassel, but Baute recommends only spraying once there’s a bit of ear on the corn. That’s because the bug can’t live on tassel the whole season, and once there’s an ear on the corn, they go to it. Sprays for worms don’t have a lasting effect, so it’s important to get all the worms at once.
