Pictured: apple maggot fly. Photo by T. McCamant UMN
Another season of orchard insect reporting has ended, with significant apple maggot and codling moth activity still occurring at some monitoring locations. Expect pest pressure to linger throughout harvest.
As is often the case, apple maggot counts have been variable this summer, according to DATCP’s Pest Survey Program. A few orchards have reported extremely high weekly captures of 10 to 25 flies per red sphere trap, while other sites have noted surprisingly few flies. Classic symptoms of apple maggot infestation, including misshapen and pitted spots on fruits and brown, internal larval tunnels, are now visible on affected fruits.
Monitoring traps for at least two more weeks is suggested since the flies are still laying eggs and could cause problems in late-ripening apple varieties.
Codling moth activity in orchards has declined markedly, though a few orchard locations registered above-threshold counts of five or more flies per trap. The cooperators in Columbia, Fond du Lac, and Marquette counties reported high weekly captures of six to 23 moths per trap. Orchards that have recorded large summer-generation flights should continue trap checks since counts in September can be an indicator of spring codling moth pressure and damage potential by the first generation of larvae next June.
Learn more: https://datcp.wi.gov/Pages/Programs_Services/AppleOrchardPests.aspx
