2022 University of Minnesota Cooperative Black Cutworm Trapping Network
Report #8 May 28- June 3, 2022
For more information: https://z.umn.edu/bcw-reporting
June 10, 2022
Greetings,
The 2022 trapping season for black cutworm wrapped up this week. Some pheromone traps for armyworms will continue for another few weeks.
There were no significant flights from May 28 to June 3. The greatest risk remains the migrating moths arriving April 29 to May 1 and to corn planted after that date. Larvae from these moth flights are large enough to cut and I’ve received scattered reports of black cutworm from Renville, Watonwan, and Nicollet County. These larvae will continue feeding for another 10 days or more and are not projected to begin pupating until June 20. Later significant flights SE and Central Minnesota will be large enough to cut corn by late next week (Table 1)
Some of the earliest planted and emerging corn in southern MN is at 4 collars so it will be a race between crop and cutworm development. Do not forget about soybean and other row crops, particularly in areas with weed escapes in 2021.
Corn at the 5-collar stage or less is most vulnerable to black cutworms, but occasionally, even slightly larger corn can be killed if large larvae tunnel into the growing point. Remember, as the corn plant grows, the growing point starts moving toward and above the soil surface and the plant becomes more susceptible to injury by cutworms at or below the growing point.
The black cutworm trapping season is ended. We will continue to track armyworm migration with a smaller number of pheromone traps and blacklight traps for a bit longer.
If you hear of cutworm damage, please let me know. I will send out updates as new information on known infestations as I receive them.
Many thanks to this year’s trap cooperators(Table 2)! I apologize if I missed someone who assisted or was delegated to run a trap(s)! We appreciated their efforts and would hope that those of you who grow or otherwise work with crops in MN do too!
The black cutworm pheromone trapping project is supported, in part, by the farm families of Minnesota and their corn check-off investment.
Enjoy the rest of the growing season,
Bruce and Travis
Table 1. Black cutworm development projections are based on historical average temperatures.
Midwest Regional Climate Center U2U https://mygeohub.org/groups/u2u/purdue_gdd
Table 2. 2022 Black cutworm pheromone trap operators.