MCOL, frontalin and ethanol: A potential operational trap lure for Douglas-fir beetle in British Columbia

. 1975; Ross and Daterman 1995b). PheroTech Inc. (now Contech, Victoria, BC) supplied all traps and lures. Chemical purities were >95% for all semiochemicals. Release rates were determined gravimetrically at 20–23 °C. Traps were suspended from a metal pole made from electrical conduit tubing such that the bottom of each trap was 0.2–0.5 m above ground level. No trap was suspended within 2 m of any tree. All lures were placed within the funnels (Lindgren 1983).The experiment was conducted in mature stands of Douglas-fir at three locations in southern British Columbia: 1) Maple Ridge (10 April–12 May 1991); 2) Cache Creek (13–31 May 1991); and 3) Invermere (30 May–8 August 1991). We used 40 12-unit multiple-funnel traps (Lindgren 1983) with dry cups in Maple Ridge and Cache Creek, whereas 20 traps were used in Invermere. Each collecting cup contained a small piece of Vapona No-Pest Strip (Green Cross; Fisons Horticulture, Mississauga, Ontario, Canada) as a killing agent to prevent damage to the target species by predatory insects. At each location, traps were set in blocks of four traps per block resulting in 10, 10, and 5 replicate blocks per location, respectively. Blocks, and traps within