Lep Monitoring Network Update #6 – Black Cutworm and True Armyworm Numbers Remain Consistent

We are now in our sixth week of monitoring for black cutworm (BCW) and true armyworm (AMW). After this week, we only have one more report for BCW and AMW until we switch lures to western bean cutworm (WBC) and corn earworm (CEW). In this newsletter article we are reporting findings from May 18^th through May 24^th. This past week was cold and rainy for the most part and BCW moth numbers remained stable whereas AMW numbers decreased.

Black cutworm

We continued to monitor 48 traps in 18 counties and this week our statewide average stayed stable (7.6 moths, down from 7.7 moths the previous week). While our peak has likely passed, BCW moths are still active in many counties across the state. This means the adults are still out and laying eggs, so make sure you are monitoring into mid-June for this pest. Counties that had averages of 7.0 moths or more are over our threshold level and encouraged to scout your fields in the next two weeks. These counties remained in northwest Ohio and included Defiance, Fulton, Henry, Putnam, Van Wert, and Wood (Figure 1).

For more information on how to scout BCW please visit: https://aginsects.osu.edu/sites/aginsects/files/imce/ENT_35_14 BCW.pdf

Black Cutworm Moth Map

Week 6: May 18^th to May 24^th, 2026

Figure 1. Black cutworm (BCW) moths captured from May 18^th to May 24^th. The bold number indicates the average moth count for the week, followed by the total number of traps in that county.

True Armyworm

True armyworm was also monitored last week with 46 traps in 18 counties (Figure 2). The statewide average for the week decreased to 7.2 moths (down from an average of 16.4 the previous week). This steep decline indicates we are past AMW peak in Ohio, and we expect numbers to continue to decline. Counties with averages higher than 7.0 moths remained in northwest Ohio and included: Fulton, Henry, Lucas, Putnam, Van Wert, and Wood. Again, we suggest that counties with a weekly average of 7.0 moths scout for AMW larvae in the coming weeks.

True Armyworm Moth Map

Week 6: May 18^th to May 24^th, 2026

Figure 2. True armyworm moths captured from May 18^th to May 24^th. The bold number indicates the average moth count for the week, followed by the total number of traps in that county.