The first presence of the brown marmorated stink bug (BMSB) in the US was documented in Pennsylvania in 2001, but it had been there since the mid-1990s. Since then this bug has been found in 41 states.
While the BMSB is not a threat to humans, it feeds on several dozen crops, including apples, pears, cherries, peaches, berries, grapes, corn, tomatoes, beans, and peppers. They also feed on many ornamental trees and shrubs, especially tree of heaven (Ailanthus altissima), Chinese pistache (Pistachia chinensis), waxleaf privet (Ligustrum japonicum), and catalpa (Catalpa spp.). In addition to being a crop pest, BMSB are also a serious nuisance to residences and businesses, as they seek lights at night and sheltered areas in the winter; they often enter buildings in large numbers in late summer and fall.
BMSB is also a pest in east Asia, where it originated, but it is generally not as serious a pest there because of control by tiny parasitic wasps. Collections of parasitic wasps (especially those in the genus Trissolcus) have been made, but before they can be released in California they need to be tested to be sure they don't also become pests themselves or harm beneficial organisms. If approved, they could be released in California as soon as 2017. In a surprise finding, BMSB egg masses have recently been found to be parasitized by T. japonicus in different locations in mid-Atlantic states. Parasitism is the best hope for reducing populations.
Control of BMSB in Urban Areas
Control of BMSB is very challenging for home gardeners. Effective insecticides have not yet been identified, and caution is urged not to kill beneficial insects or contaminate waterways with pesticides in runoff water. See the UC Pest Note on BMSB.
Control on and in buildings is also difficult, and exclusion is the primary means of control. Insecticides can be used to kill aggregations (clusters) of them in late summer/fall by contact, but using insecticides for residual control around small entrances is not recommended; and both practices can lead to pesticide runoff into waterways. Commercial pest management vacuums are available and are very effective.
What does marmorated mean? - Marmorated: variegated like marble; covered or overlaid with marble. This refers to the speckled look on the back of adult bugs.
Fact Sheet (PDF 600kb) - Identification, damage, and tree hosts - July 2015 (UC ANR)
Pest Note - Management of BMSB in Homes and Gardens (UC IPM)
Pest Alert - Brown Marmorated Stink Bug Identification (UC IPM)
Article - Excluding Seasonal Nuisance Pests on Structures (UC IPM)
Presentation (PDF 1.2MB) - Overwintering Pests--Control Strategies (National Pest Management Association)
News Release - September 18, 2013 (UC ANR)
Video - BMSB Control: Keeping Stink Bugs Out of Your House (University of Maryland Extension)
Video - Compare BMSB with Consperse Stink Bug (UC ANR)
Streaming - Presentation on BMSB (Tracy Leskey, USDA)
StopBMSB.org - National BMSB web site
Map - BMSB populations in the US (stinkbug-info.org)
BMSB in California Agriculture - (UC ANR)