After several years of low corn rootworm pressure (CRW), adult populations of this insect were reported to be on the rise in Illinois. Data collected in August by the University of Illinois reports a large number of adult Western CRW beetles in corn fields. Higher populations were observed primarily in the northeast and West, with results showing much higher adult beetle counts than the 6 year average.

The 2 species to look out for are Western and Northern CRW beetles. Looking ahead, some things to keep in mind about these insects include:

• Eggs are laid in mid-to-late summer and overwinter.
• Eggs hatch from mid-May to early June
• Larvae start feeding within 3-4 hours of hatching

        Larvae                         Western              Southern

With a high number of beetles spotted in August, what does this mean for the 2018 season? While factors like temperature and weather over the next few months can affect the larval survival rate, it is still important to recognize the rising population and prepare accordingly. We suggest an insecticide like Force® Evo or Force® 3G that helps protect developing corn root systems against insects. For more information, please contact your local Syngenta Sales Representative.

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