Three sizes of the Conrel Delta trap, a yellow cardboard tube trap, and the Pherocon II standard trap generally used in detection surveys were evaluated. Tests were run for 41 days in the summer of 1980 and 35 days in the spring of 1981. The lure in all traps was the standard 38-cm cotton dental roll charged with 10 female equivalents of crude virgin female pheromone extract. In 1980, all test traps outperformed the standard Pherocon II model. In 1981, the Pherocon II traps captured more males than any of the others. The catch in the Delta traps appeared to be Toughly proportional to their size. An additional test in 1981 evaluated three types of cigarette filters compared with the dental roll as the pheromone dispenser. After 79 days, the cigarette filter-baited traps were still capturing sawflies whereas the traps baited with the dental rolls stopped catching males after 51 days.
Thomas, H. A.
"Field Evaluation of Trap Components for the Introduced Pine Sawfly, Diprion Similis (Hymenoptera: Diprionidae),"
The Great Lakes Entomologist, vol 16
Available at: https://scholar.valpo.edu/tgle/vol16/iss1/3