Studies conducted in Israel throughout 1978 resulted in the development of an improved pheromone trap for capturing large numbers of maleSpodoptera littoralismoths in the field. The dry open trap is dusted on its interior walls with 4% diazinon to prevent the escape of moths attracted therein by a dispenser releasing the insect's synthetic sex pheromone, and it remains effective for 4 weeks without replenishing either the pheromone or the insecticide. Captures were 3 times greater with diazinon than with talc or silicates (Charsit and Wessalon).