Frontalin interrupts attraction of Ips pini (Coleoptera: Scolytidae) to ipsdienol

The pine engraver, Ips pini (Say), breeds in the phloem tissue of dead, dying, or downed pines, occasionally attacking standing live trees when populations build up to significant levels following logging activities or infestations by the mountain pine beetle, Dendroctonus ponderosae Hopkins (Furniss and Carolin 1980). In British Columbia, I. pini uses ipsdienol as an aggregation pheromone to facilitate large aggregations of mated beetles and breeding galleries (Miller et al. 1996). The aggregation pheromones, exo-brevicomin and cis- and trans-verbenol, used by D. ponderosae (Borden et al. 1987; Miller and Lafontaine 1991) interrupt attraction of I. pini to ipsdienol (Miller 1991). Another semiochemical, frontalin, is used by D. ponderosae as a multifunctional pheromone (Borden et al. 1987), enhancing attraction of beetles at low release rates and interrupting attraction at high release rates. I tested the effect of frontalin, over a broad range of release rates, on the attraction of I. pini to ipsdienol-baited traps.