During the past spring and summer glass barrier traps have been used as a means of sampling the flying populations of an ambrosia beetle, Trypodendron sp., and other scolytid beetles. The “window” trap has functioned well enough to warrant its brief description. A piece of window glass (2 × 2 ft.) is set in a three-sided wooden frame from which a sheet metal trough is hung. The trough is filled with fuel oil or water to which a wetting agent is added. Screened outlets provide for drainage of excess rain water in the laner case and when oil is present an inverted “L” tube drains this water from beneath the oil. Insects are collected by removing the trough and pouring its contents through a strainer. Traps are hung from various types of pole framework depending on their location, and guy wires are used to keep them from swinging.