The brown marmorated stink bug insect affects a wide segment of Oregon society including citizens, business owners, and farmers.
Where in Oregon is the pest?
BMSB is present in most Oregon counties throughout Oregon, but is most prevalent in the Willamette Valley, where BMSB can be locally abundant in urban, rural, and natural areas. In eastern and southern Oregon, BMSB has been largely restricted to urban areas where the greatest concentration and diversity of deciduous trees are found. BMSB can be locally abundant in urban, rural and natural areas.
Oregon offers BMSB a comfortable environment with abundant habitat and less pressure from natural enemies than it has in its native range of China, Korea, and Japan. However, that may be changing as its chief natural enemy in Asia was discovered in 2015 along the Oregon border in Vancouver, WA and in 2016 in Portland. The beneficial natural enemy has recently been found in Salem and Beaverton, and we expect that it will continue to spread. This natural enemy is a minute wasp (1-2 mm) called Trissolcus japonicus. Female wasps seek out the egg masses of BMSB, and they lay their own eggs inside. Instead of the BMSB eggs hatching with BMSB nymphs, they instead produce a new set of wasps. They don’t sting people but Aa clear sign of their activity are BMSB egg masses that darken to a black color. They don’t sting people.BMSB is present in counties throughout Oregon, but are most prevalent in the Willamette Valley where BMSB can be locally abundant in urban, rural and natural areas. In eastern and southern Oregon, BMSB has been largely restricted to urban areas where the greatest concentration and diversity of deciduous trees are found.
Why report BMSB?
While BMSB is no longer a new invader in western Oregon, and many of us have become desensitized to its constant presence around our homes and farms, the information provided in the reports is still very useful for us. The invasion of BMSB is still occurring in the eastern and southern part of Oregon and the reports help us document the invasion in those areas. We can gain useful insights about the pest in terms of its environmental associations and the timing of your observations. We are also very interested in reports of the pest attacking agricultural commodities, so that we can better direct our research and Extension efforts.
Hover your cursor over the map below to view sightings reported by county.