Insect Alert For

Corn Earworm

Risk Level:
Moderate Risk
Affected Area:
Full page
Alert Details

A strong cold front is predicted to pass through most of the corn-growing region over the holiday weekend. Ahead of the front, however, south to southwest winds should remain persistent and scattered showers and thunderstorms are also likely to accompany the frontal passage as well. As a result, corn earworm migration and drop-out risks are in the Moderate category for the potential for a late season moth flight across much of the corn-growing region especially across portions of Kansas, Nebraska, southern South Dakota, southwest Minnesota, western Iowa, and far northwest Missouri tonight into Saturday morning. The risk area expands as far east as the Great Lakes region and eastern Midwest for Saturday night into Sunday morning as the front begins advancing southeast and also as high pressure moves further into the southeastern United States which will likely lead to increased southerly wind coverage further east. Moderate risks are in place across portions of Kansas, Nebraska, South Dakota, Minnesota, Wisconsin, Iowa, Illinois, Missouri, Indiana, Ohio, and Michigan for tomorrow night into Sunday morning. The front will continue east into Sunday and Monday but wind speeds are expected to be lower and also winds may be coming from a less favorable direction by that time so only risks are predicted mainly east of I-57 in Illinois. Corn earworm trap counts have increased in many locations especially across the upper Midwest this week and treatments are ongoing in many sweet corn fields. Growers with late planted, slower maturing, or fresh market and processing crops that are still at susceptible stages to insect damage should be monitoring their fields very closely over the next several days and be prepared to take action as this late season flight continues. High pressure builds into the Plains and upper Midwest and eliminates any migration risk by early next week.