Inhibition by Ipsenol of Pine Engraver Attraction in Northern Idaho

Ponderosa pine log sections, infested with 25 male Ips pini Say or uninfested, were tested for attractiveness in spring and summer with and without ipsenol. Ips pini were caught abundantly only on traps containing male infested logs. Ipsenol eluted at ca. 2 mg/day was more effective in reducing catch than were 2 lesser rates. Seventeen species of bark beetles and 4 species of predacious beetles were tallied on traps. Beetles other than I. pini that were attracted in significantly greater numbers to one or more treatment were the scolytids Orthotomicus caelatus (Eichhoff) and Ips latidens LeConte; and the c1erid Enoclerus lecontei (Wolcott).