As our moth flight picks up, we need to be very aware about corn earworms (bollworm) infestations in soybean. It can be very destructive. Infestations most often occur in late maturing fields. Moths are most attracted to beans during R1 – R3 (early flowering), and open canopies really turn them on. Typically, problems are worse in the Mississippi River Bottoms, but assume nothing.

The sweep net is the preferred method of sampling, and the suggested treatment threshold is based on the cost of the insecticide application, including application costs, and the commodity price ($/bushel) of soybean. Please see the table below.

Increasing pyrethroid resistance has made insecticide control more expensive. I do not trust pyrethroids and would suggest using products like Blackhawk (1.7-2.2 oz), Besiege (6-8 oz/acre), Intrepid Edge (4-6 oz/acre), Prevathon (14 oz/acre), or Radiant (4 oz/acre), or Steward  7-10 oz/acre).