THE PHEROMONE OF THE EASTERN TENT CATERPILLAR, MALACOSOMA-AMERICANUM (F) (LEPIDOPTERA, LASIOCAMPIDAE)

The pheromone system of the eastern tent caterpillar, M. americanum, h as been identified as a mixture of (E,Z)-5,7-dodecadienal and the corr esponding alcohol. Field data on the attractiveness of the aldehyde al one were not consistent, but mixtures of aldehyde and alcohol in varyi ng proportions were attractive to males. Addition of small amounts of E,Z acetate to E,Z aldehyde had no effect on male response, but larger amounts reduced trap catch. Traps baited with Z,E, E,E, or Z,Z aldehy des were not more attractive than blank traps. Pherocon 1C traps forti fied with extra adhesive and baited with lures consisting of 500 mu g (E,Z)-5,7-dodecadienal with either 250 or 100 mu g of the correspondin g alcohol trapped as many as 100 males/trap/night with means of 15-20. Lures prepared from purified (94% E,Z) aldehyde and alcohol were more attractive than those prepared from unpurified (58% E,Z) materials.