Issue No. 3, Article 3/April 13, 2007
Captures of Black Cutworm Moths Reported
Some black cutworm moths slipped into the state before temperatures dropped this past week. In at least one instance, an intense capture (nine or more moths over a two-night period) was observed. These early arriving moths will seek oviposition sites, such as winter annual weeds, and lay eggs that will develop into the first cutworm larvae we will encounter this spring.
Several people have reported capturing black cutworm moths in pheromone traps during the last week in March and first week in April, although few have captured enough moths to designate an intense capture. However, Mike Roegge, University of Illinois Extension crop systems educator in Quincy, reported that Earl Boone, Pioneer Hi-Bred International, had an intense capture on April 2 and 3. By plugging the date of April 3 into the degree-day calculator for black cutworms, I learned (on April 10) that the projected date for 300 degree-days (early signs of cutting) to accumulate is May 14--still a ways off. Dave Feltes, University of Illinois Extension IPM educator in the Quad Cities, captured seven black cutworm moths on April 4 in his pheromone trap in Whiteside County. Although that is not a significant capture, the occurrence of black cutworm moths that far north in Illinois this early in the spring is worth noting.
The supply of moths to keep the egg supply steady will be affected significantly by frontal systems and the flow of air over the Midwest over the next few weeks. It's still much too early to determine whether black cutworms will pose a threat anywhere after significant corn planting gets underway, but it's not too early to note their presence. We invite continued reports of captures of black cutworm moths, and we'll let you know how things are developing.--Kevin Steffey