Abstract
The ovipositional response of Monochamus alternatus to Pinus densiflora bolts occupied by oviposition scars containing eggs or live larvae was investigated. Pine bolts were pre-conditioned by exposure to various combinations of females and males prior to allowing females to oviposit, . Deterred oviposition was found on pine bolts heavily infested with oviposition scars which had been made by the same or a different female. When infested pine bolts were made by exposure to females together with males, deterred oviposition occurred on the heavily infested pine bolts exposed to different females but not on those exposed to the same females. In significant oviposition deterrence was found on pine bolts lightly infested with scars made by the same or different females together with males. Strongly deterred oviposition was observed on pine bolts infested with oviposition scars containing live larvae.