Plum Curculio ( Conotrachelus nenuphar Herbst) larval success was assessed for infested apples treated with insecticides. Infested fruit (20mm diameter) were collected from the field and dipped in field-rate solutions of various insect growth regulator, neonicotinoid, organophosphate, oxadiazine or pyrethroid insecticides. Larval emergence, timing and final larval mass were compared across treatments. Effectiveness of treatments is discussed relative to the fruit cuticle penetration data that have been developed for these chemistries.