Attraction of Lasconotus Intricatus Kraus. (Coleoptera: Colydiidae) to the Aggregation Pheromone of the Four-Eyed Spruce Bark Beetle, Polygraphus Rufipennis (Kirby) (Coleoptera: Scolytidae)

The cylindrical bark beetle, Lasconotus intricatus Kraus., is attracted to multiple-funnel traps baited either with black spruce logs infested with male four-eyed spruce bark beetles, Polygraphus rufipennis (Kirby), or the male-produced aggregation pheromone, 3-methyl-3-buten-1-ol. The addition of the host terpenes, bornyl acetate and β-pinene, to 3-methyl-3-buten-1-ol reduced the attraction of L. intricatus. 3-Carene, myrcene, and α-pinene appeared to have a partial inhibitory effect. Catches in spring and summer disclosed a high degree of temporal coincidence between the two species. We hypothesize that L. intricatus utilizes the aggregation pheromone of P. rufipennis as a host-finding kairomone.