Trapping Update
Between April 27 and May 3, 19 trap sites reported a total of 99 black cutworm moths captured in traps (Figure 1). There were two significant flights during the week (Figure 2), including Washington County on April 26 and Jackson County on April 28.
Using historical temperature data from the Midwest Regional Climate Center database, Table 1 shows the current projected cutting dates in counties that have had a significant flight. Actual spring temperatures will change these projections, so stay tuned to weekly updates! Remember that it is recommended to begin scouting well before these predicted dates to find larvae before they cut plants.
| County (Crop Reporting District) | Significant Flight Date (Biofix) | Projected Cutting Date |
|---|---|---|
| Tama (Central) | April 12 | May 10 |
| Jackson (East Central) | April 12 | May 9 |
| Polk (Central) | April 13 | May 10 |
| Buena Vista (Northwest) | April 22 | May 23 |
| Cerro Gordo (North Central) | April 22 | May 23 |
| Franklin (North Central) | April 22 | May 23 |
| Marshall (Central) | April 24 | May 30 |
| Tama (Central) | April 24 | May 30 |
| Washington (Southeast) | April 26 | May 22 |
| Jackson (East Central) | April 28 | May 30 |
These dates may differ from what was reported in the ICM News article about predicted cutting dates for a few reasons: I update the blog weekly using actual temperature data, and cutting dates for regions without traps or significant flights are our best estimates based on available data. Plan to scout for black cutworm as crops emerge this spring!
More Information
For more information on black cutworm identification, injury, and management options, read the black cutworm encyclopedia article. You can find previous weekly reports on the ICM Blog.
Surrounding states also monitor and report black cutworm captures, as well as other moth species. If you live near the state border, it may be beneficial to check these resources periodically. More resources may be available than those listed here:
Links to this article are strongly encouraged, and this article may be republished without further permission if published as written and if credit is given to the author, Integrated Crop Management News, and Iowa State University Extension and Outreach. If this article is to be used in any other manner, permission from the author is required. This article was originally published on May 6, 2026. The information contained within may not be the most current and accurate depending on when it is accessed.
- Extension Specialist II