β-Phellandrene: kairomone for pine engraver,Ips pini (Say) (Coleoptera: Scolytidae).

The responses ofIps pini (Scolytidae) to multiple-funnel traps baited with the pheromone, ipsdienol, and various monoterpenes were determined in stands of lodgepole pine in southern and central British Columbia.Ips pini was attracted to both ipsdienol and β-phellandrene, demonstrating that β-phellandrene is a kairomone for this species.Lasconotus complex (Colydiidae) and aCorticeus sp. (Tenebrionidae) were attracted to both ipsdienol and β-phellandrene. TheCorticeus sp. exhibited a synergistic response to the combination of ipsdienol and β-phellandrene; the responses of the other two species to the combination were additive. The predators,Thanasimus undatulus, Enoclerus sphegeus, andE. lecontei (Cleridae), were attracted to ipsdienol-baited traps, whileMonochamus clamator (Cerambycidae) andDendroctonus ponderosae (Scolytidae) were attracted to β-phellandrene. Attraction of all eight species increased with increasing release rates of ipsdienol and/or β-phellandrene.