Soybean Insect Pest Update
Green cloverworm has been increasing in soybean fields. These green worms feed on the underside of leaves and fall to the ground when soybean plants are shook. Worms leaf feed and economic threshold is 20% leaf defoliation and 10 to 15 more half grown larvae are present per foot of row.
Typically, a fungus attacks these worms and therefore we have natural control. Worms infected seem sick and will stop feeding. Death of the cloverworm occurs in one to two days. As you scout, be sure to examine insects carefully as they change to a whitish color when infected.
Other pests commonly found are also commonly found in soybean fields. Scouting should continue for bean leaf beetles and stink bugs. As far as economic thresholds for bean leaf beetle during pod fill, treat with an insecticide when 5% to 10% of pods are damaged, plants are still green and numerous beetles can be found in the field. Stink bugs should be treated when one or more stinkbugs are found per foot of row during pod fill.
For more information, contact Wayne Flanary at 660-446-3724 or Kurt Nagel at 816-776-6961, Extension Agronomists, University of Missouri Extension.
Thank you for your continued support of Extension programming.
Tracy Shewey, Office Manager
University of Missouri