Issue No. 12, Article 4/June 11, 2004
Heads-Up (or Heads-Down) on European Corn Borer
As we move into June and corn plants grow by leaps and bounds, questions about infestations of European corn borer begin. In issue no. 10 of the Bulletin (May 28, 2004), Mike Gray discussed the potential establishment of corn borers in early June. Generally, moth flights in early June determine the success of the establishment of first-generation corn borers.
Currently, moth flights have been low, but they seem to be on the rise. The light trap monitored by John Shaw, Illinois Natural History Survey, in Champaign has captured only 2 corn borer moths through June 4. Mark Hoard, Extension educator, IPM, has had a few more moths in the trap he monitors in Franklin County. Jim Donnelly, Ag View FS, had a peak nightly catch of 46 moths on June 6 in Lee County. At this same time last year, Adams County recorded 47 moths on June 6, and four light traps in Mason County averaged 30 moths a night during the second week of June. Those same traps then caught upward of 100 moths the following week.
While corn borer moth flights have been low, some larval feeding is being seen in fields of knee-high corn. Mike Roegge, Adams/Brown counties, found some 1st-instar European corn borer larvae feeding in V6-V7+ corn. While damage is not at economic levels, he did notice pinhole feeding on older leaves of the corn plants. Even though we are receiving mixed reports of European corn borer activity, be sure to scout cornfields and keep your heads down for corn borer feeding. --Kelly Cook