Insect Alert For

Corn Earworm

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

A very persistent and blocked weather pattern is predicted to hold across much of the corn-growing region right into next weekend. High pressure remains anchored over the eastern corn-growing region while an upper level trough and weak low pressure systems remain over the western Plains. In between these two features, south to southwest winds will be rather persistent in a corridor from Kansas and Missouri north northeast into Nebraska, Iowa, South Dakota, Minnesota, western Wisconsin, and eventually as far north as North Dakota and central/northern Minnesota. Low risks are in place in this corridor for the next five nights, and the overall risk area changes little during this time other than a slight expansion both to the north into the I-94 corridor in North Dakota and Minnesota by late week and next weekend, and east into Wisconsin and the Mississippi River valley by Saturday night into Sunday. Despite a pretty favorable weather pattern for migration, many fields are not past susceptible stages to damage and those fields that are still at risk (notably fresh-market and processing fields) already have scattered to widespread corn earworm populations from previous flights in the past few weeks. Additionally, the source region being in Kansas, Oklahoma, and Texas usually does not result in larger-scale flights compared to those source regions further to the east. Nonetheless, the duration of south to southwest winds may result in at least isolated new flights this week and into next weekend, so growers should continue to monitor traps and scout fields.