Field trials were carried out in Malawi with (Z)‐8‐dodecenyl acetate and a 1: 1 mixture of (Z)‐8‐dodecenyl acetate and (E)‐8‐dodecenyl acetate, which were previously identified as the female sex pheromones ofCryptophlebia batrachopaMeyrick andC. leucotretaMeyrick (Lepidoptera: Tortricidae) respectively. Catches of male moths in cardboard sticky delta traps baited with the respective pheromones were highly significantly correlated with knock‐down counts for each species. Polyethylene vials were shown to be more effective dispensers for the pheromones than rubber septa. An initial pheromone loading of 1·0 mg was as effective as 5·0 mg and significantly more effective than 0·1 mg when assessed over 4‐week periods. The experiment suggested that vials impregnated with 1·0 mg of pheromone started to lose their attractiveness after about 6 weeks and were virtually unattractive after 12 weeks in the field.