The weather warmed up a bit during Week 5 (April 25 to May 1), and the moths were flying more than previous weeks. During Week 5 of the Iowa Moth Trapping Network, our cooperators reported 97 total black cutworm (BCW) and 33 true armyworm (TAW) moths.
Week 5 report:
The 33 TAW moths reported during Week 5 were captured sporadically throughout the week and mostly in the southern half of the state (Figure 1). Black cutworm activity was statewide (Figure 2). Over half of the BCW moths were reported on April 28th and 29th. Three significant flights and one potentially significant flight occurred during the week:
- Taylor County on April 26 (previous significant flights on April 8 and April 18)
- Carroll County on April 29
- Pottawattamie County on April 29
- A potentially significant flight occurred in Mahaska County on April 30 (previous significant flights on April 8 and April 12)
You can read more about what a significant flight means in the Week 2 update.
These updates are typically a week behind. If you are interested in staying up-to-date on the moth trapping network, visit https://corn.ipmpipe.org/insects/ to see live mapping from Iowa, Wisconsin, and Illinois. The true armyworm and black cutworm pages feature 1) an interactive map showing the total count for the current 7-day window – clicking on a county will show you a line graph of trap captures, and 2) a time-lapse map of counts for the entire season. The black cutworm page also has a map that I will update with predicted cutting dates (note: this map is not real-time).
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: