Effects of bark beetle pheromones on the attraction of Monochamus alternatus to pine volatiles

We evaluated the attraction of Monochamus alternatus Hope (Coleoptera: Cerambycidae), Dryocoetes luteus Blandford and Orthotomicus erosus Wollaston (Coleoptera: Curculionidae: Scolytinae) to multiple‐funnel traps baited with the pine volatiles, ethanol and (+)‐α‐pinene and the bark beetle pheromones, ipsenol and ipsdienol. M. alternatus were attracted to traps baited with ethanol and (+)‐α‐pinene but not those baited with ipsdienol and ipsenol. Ipsdienol and ipsenol decreased catches of M. alternatus in traps baited with ethanol and (+)‐α‐pinene. Traps baited with either binary combinations of ethanol and (+)‐α‐pinene or ipsdienol and ipsenol were attractive to D. luteus and O. erosus. The addition of ipsenol and ipsdienol to traps baited with ethanol and (+)‐α‐pinene synergized attraction of O. erosus but not D. luteus.