In field tests with the two component sex pheromone ofAmorbia cuneana, (E.Z)-10,12- and (E,E)-10,12-tetradecadien-1-ol acetates, optimum trap catches were obtained with an isomer content of 29 to 82% EZ (as a percentage of EE + EZ), and dosages of 0.06 to 1.7 mg per rubber septum (using a bait of 62% EZ). There were slightly larger catches for the bait with 53% EZ than for others in the 29 to 82% range. Individual native femaleA. cuneanamoths contained an average of 54.8 ± 10.2% EZ (range = 33.7–69.6% EZ). Traps baited with synthetic pheromone caught as many males as traps baited with females. Catches were higher when rubber septa were used to dispense the pheromone than when polyethylene caps were used. A synthetic contaminant, (E)-/(Z)-10-dodecen-1-ol acetate, was found to be moderately inhibitory. Rubber septa baited with synthetic pheromone and aged in the field for 90 days were as effective as fresh baits. During the entire aging period of 120 days, the EZ isomer content changed from 62 to 33%.