Ponderosa pine log sections, infested with 25 maleIps piniSay or uninfested, were tested for attractiveness in spring and summer with and without ipsenol.Ips piniwere 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 thanI. pinithat were attracted in significantly greater numbers to one or more treatment were the scolytidsOrthotomicus caelatus(Eichhoff) andIps latidensLeConte; and the c1eridEnoclerus lecontei(Wolcott).