Agricultural Engineering/Agronomy, Central Iowa, and BioCentury Research Farms

Re-evaluating Trapping Recommendations for Corn Rootworm Adults

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Abstract

Western corn rootworm (Diabrotica virgifera virgifera; WCR) and northern corn rootworm (Diabrotica barberi; NCR) larvae are the most significant insect pests of corn across the Midwest region. Because larvae live in the soil and are difficult to scout, current management recommendations rely on capturing adult beetles on at least 12 yellow sticky traps monitored and replaced for at least six weeks during the growing season. The current threshold is two beetles per trap per day; if this is met, farmers are encouraged to change management tactics the following spring to minimize yield losses. Because the scouting procedure is tedious, expensive, and largely unacceptable for most farmers, this research aims to refine the optimal scouting window for corn rootworm adults using fewer traps. Additionally, there is speculation that the trapping threshold is too low, and needs revised based on current hybrids and market conditions.

How to Cite:

Hodgson, E. W. & Dean, A., (2025) “Re-evaluating Trapping Recommendations for Corn Rootworm Adults”, Iowa State University Research and Demonstration Farms Progress Reports 2024(1), 11-13.