Exotic woodboring Coleoptera (Micromalthidae, Scolytidae) and Hymenoptera (Xiphydriidae) new to Oregon and Washington.
Concerns about the unintentional introduction of exotic wood-boring insects prompted surveys of high-risk sites in Washington, USA in 1996 and Oregon, USA in 1997 and 1998. Ports, port areas, mills and businesses known to have received or handled imported wood or wood products were monitored using Lindgren funnel traps and/or Scots pine bait logs. Seven species of beetles, Micromalthus debilis (Micromalthidae), Gnathotrichus materiarius, Hylastes opacus, Xyleborinus alni, Xyleborus californicus, Xyleborus pfeili, Xyloterinus politus, and one species of wood wasp, Xiphydria prolongata (Xiphydriidae), are recorded from Oregon, Washington, the western United States, or North America for the first time. These species are native to Asia, Europe, or the eastern United States. Most probably pose little immediate threat to the overall health of our forests, agricultural systems, and urban or rural environments. Hylastes opacus, a Palaearctic species previously established in the eastern U.S., is a known pest of pines. Xiphydria prolongata has been implicated as a passive carrier of watermark disease of willows. Six (75%) of these species have hardwood hosts, implicating dunnage and solid wood packing material as probable pathways of introduction. Thirty-eight percent of the sites monitored in Oregon produced one or more new species records. These detections underscore the need for (1) effective regulations and certification, quarantine, and port inspection programmes to prevent the introduction of exotic wood-boring insects and (2) for systematic surveys of high-risk areas to determine which introduced organisms may already be established.