The brown marmorated stink bug (BMSB) is an exotic insect pest. Native to China, Japan, Korea and Taiwan, it was accidentally introduced to the US and is now found in 29 states. It has not yet established itself in California, but a colony of BMSB was identified and destroyed by the California Department of Food and Agriculture (CDFA) in a storage facility in Vallejo, Calif., in March 2005.

There is growing concern that BMSB may eventually become established in California, a very undesirable possibility, as the BMSB is a major economic pest in Asia attacking a variety of high value crops, including tree fruit, and BMSB has damaged stone fruits and apples in the Eastern United States.

Adult BMSB resemble other stinkbugs. They have a marbled pattern on their backs and specialized mouthparts that enable them to penetrate and feed on plant tissues. Feeding results in fruit deformation (cat‐facing), and internal brown spotting that renders the fruit unsuitable for fresh market.

The BMSB can emit a foul odor; the presence of BMSBs in wine grape clusters at harvest and crush may contaminate the fruit and impart their foul bitter‐sweet odor to the wine.

More information on the BMSB is available online: