Brown marmorated stink bug: a growing problem in Washington state and the discovery of an exotic egg parasitoid

Brown marmorated stink bug (BMSB) Halyomorpha halys (Stål) establishment has been increasing steadily in the past five years in Washington state. It is well established in the Vancouver area, and in the Seattle-Tacoma metropolitan area. Finds have been common along the Columbia River as it borders Oregon, with a significant population as far east as Walla Walla. There have also been multiple finds in Yakima and the Tri-Cities areas, and in the fall of 2015, multiple finds in northcentral Washington. Sampling methods have included a newly available pheromone, and beating tray sampling of favored tree hosts. The ecology of BMSB in the arid shrub-steppe environment of eastern Washington may be very different than the mid-Atlantic states, but given the success of many species of native stink bugs to thrive here, we can also expect BMSB to establish.  Outreach efforts have included presentations at meetings, online and print literature on identification and biology, and training county pest boards in sampling and recognition. The most significant progress in the future management of BMSB was made in the fall of 2015 with the discovery of an exotic scelionid egg parasitoid, Trissolcus japonicus (Ashmead), which unlike native parasitoids, is well adapted to BMSB. The discovery of three parasitized egg masses in Vancouver, WA, was the first record of this species on the west coast of North America.