Fewer moths were reported last week than in previous weeks, but even so, the northward migration of two pest species continues. During week 4 of the Iowa Moth Trapping Network (April 23 to April 29), our cooperators reported 71 black cutworm (BCW) and 85 true armyworm (TAW) moths around the state. There was only one potentially significant flight of black cutworm last week (refer to the Week 2 update for an explanation of significant flights and my classification of potential significance).
Week 4 report
Most of the TAW moths reported last week flew in between April 28 and April 29. The BCW moths reported last week seemed to arrive consistently throughout the week. The potentially significant flight occurred on April 24 in Keokuk County. Figures 1 and 2 show the Week 4 trap reports for true armyworm and black cutworm, respectively.


Follow the links to see the report from Week 1, Week 2, or Week 3. You can also track moth flights and black cutworm significant flights for Iowa, Illinois, and Wisconsin at https://corn.ipmpipe.org/insects/.
Surrounding states also monitor and report BCW and TAW captures. If you live near the state border, it may be beneficial to check these resources periodically. More resources may be available than what is listed here:
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