By John Wise
Following low levels of apple maggot adult emergence during most of July, high numbers of apple maggot have been detected in August at the Michigan State University Trevor Nichols Research Center in Fennville, Michigan. Controlling apple maggots has been traditionally achieved with organophosphate insecticides, like Imidan. Synthetic pyrethroid compounds, like Asana, Warrior, Danitol, Battalion, Mustang Max and Baythroid, are also toxic to adult fruit flies but are generally viewed to be moderately effective because they have a shorter field residual. There are several reduced-risk and organophosphate-replacement insecticide products that include apple maggot on their labels.
The neonicotinoids Belay, Admire and Assail are labeled for apple maggot control. They have limited lethal action on adult apple maggots but provide strong curative activity on eggs and larvae. The METI compound, Apta, is toxic to adult fruit flies as a contact insecticide. The Spinosyn compounds Delegate and Entrust are active on apple maggots when ingested but have shown to be only fair control materials in field trials with high pest pressure, thus are labeled for apple maggot suppression only. Venerate is an OMRI approved biopesticide that is labelled for apple maggot control.
The Diamide compounds Exirel, Verdepryn and premix Minecto Pro (diamide plus avermectin) are active on apple maggots and labeled for population suppression. Leverage, Voliam Flexi and Endigo are pre-mix compounds that are labeled for apple maggot control.