On July 18 we reached Apple Maggot threshold of 5 flies per trap, in a block of mixed variety apple in which we were monitoring baited red sticky spheres at the Hudson Valley Lab. Recent rains have provided optimum conditions for adult emergence.
The red spheres are very attractive to mature adult female AM flies, ready to oviposit. From work done by Chapman and Link, the apple maggot will first infest early apple varieties such as Ginger Gold, moving to later maturing varieties as the season progresses. Summer and early fall maturing varieties are particularly vulnerable, with thin skinned sweet and sub-acid varieties being most susceptible. These fruit should be protected upon trap threshold as they will be infested this week if emergence builds throughout the region.
Materials for management of the apple maggot should also be effective at controlling the codling moth (CM) as it emerges this week.
Insecticides effective against both AM & CM include: