Corn rootworm flight is really taking off this week in Sumas and south Abbotsford and probably elsewhere. There are loads of beetles flying; they are really active in some locations. Corn silks are getting snipped, leaves look bleached out from feeding, and nearby flowers seem to be aggregation places for beetles, in particular, in melon flowers. The beetles seem to like eating red-root pigweed.
They are attracted to anything yellow, including our traps. Besides logging the flight pattern over time, traps can be used to anticipate the risk for the next year in the field. Once we have some counts done we will have a better idea of how this will work for BC growers.
Growers are concerned and some want to spray the beetles to prevent silk damage. The only insecticide registered for this use is Sevin (Carbaryl). In 2016, Sevin was used successfully for beetle control on at least one farm. If fields are still short enough to drive equipment through this is an option. A spray won’t entirely prevent egg laying in the field but will help prevent silk damage.
Prepared by: Tracy Hueppelsheuser, B.C. Ministry of Agriculture Tracy.Hueppelsheuser@gov.bc.ca
Corn rootworm on melon flower.