Corn Rootworm and the Soybean Variant: Volunteer Corn Creates "Safe Harbor" for Rootworm

While driving across the Iowa countryside this summer, one can’t help but notice all the stalks of volunteer corn ascending from the soybean fields like a sentry on duty.  A sentry usually prevents the passage of unauthorized persons.  In a cornfield, however, the volunteer corn actually serves as a “safe harbor” for corn rootworm.

Corn rootworms essentially need corn to survive.  That’s why a corn-soybean rotation has been an effective control measure.  When corn appears in a bean field, however, the rootworm beetles have a food source and then a place to lay their eggs.  Most eggs are laid in the upper 6” of soil during late summer.  Eggs remain dormant until the following spring, so they’re “ready to feast” on the next crop of corn.

Applying a tank mix treatment to clean up volunteer corn will help you avoid the soybean variant in the rootworm beetle on your acres in 2012.  Click the video link below for more information.  Additional information on the soybean variant of western corn rootworm is available from this publication by Iowa State University.