When microencapsulated (E)-11-tetradecenyl acetate (E-11-tda) or 11-tetradecynyl acetate (11-tdya) were sprayed in the field at various rates, the rate of capture of male European com borers,Ostrinia nubilalis(Hübner), and redbanded leafrollers,Argyrotaenia velutinana(Walker), in pheromone traps was suppressed for 3 wk compared with the rate of capture in untreated plots. An application ofE-11-tda disrupted sex attraction of both moth species as much as 10 m from the site of application. The best strategy to achieve mating control over a pest-insect population may involve use of compounds that disrupt distance communications in combination with other compounds that would disrupt short-range pheromonal communications.