Brown Marmorated Stink Bug (BMSB) Update

An adult was collected this week in one of our pheromone traps at a mixed tree fruit farm near Beamsville, ON. In addition, a BMSB nymph was collected on a Catalpa tree at a residential home in St. Catharines, ON (other nymphs were spotted in the same location but were too high in the canopy to collect). An established breeding population has been identified in the City of London, ON (See below for more information and locations.)

BMSB has not yet been detected in the crops themselves, but this pest can be tricky to spot at low densities. In addition, the adults are highly mobile. At this point in the season, all life stages of BMSB will be present (eggs, nymphs, adults). If the season is similar to that experienced in 2013, we should see the first new adults (those originating from early egg masses laid by overwintering adults) in the next week or two. If you haven't started monitoring in your crops (peach is an early crop host) and in the landscape along crop borders, consider doing so now. Buckthorn, Catalpa, lilac, Manitoba maple, black walnut and Tree of Heaven are good early wild hosts, but there are many others.

Make sure to look for signs of stink bug injury, especially along crop borders near woodlots, hedgerows, the Escarpment, etc. Early injury in tree fruit ('catfacing') looks like water spots or small areas of bleeding, becoming depressed or sunken as fruit develops. In apples, injury may take 2-3 weeks before it is obvious. Injury to tomatoes or peppers appears as discoloured spots, with light-coloured spongy tissues under the skin. More descriptions and pictures are available on our webpages at

Thresholds and management programs are still being developed in the mid-Atlantic US, where BMSB is abundant. Scouting is always important, on the crop and landscape hosts. Finds of adults in traps are indicative that BMSB are established in the area but they do not always mean insecticide sprays are necessary. Pheromone traps are being recommended for use as early detection tools, to trigger intensive scouting in crops and insecticide applications. Traps are typically placed between crop borders and woody landscape hosts OR within the crop border. If adults or nymphs are found in traps outside of the crop, intensive monitoring is needed. If nymphs are found in traps placed within a crop border, sprays are triggered. In tree fruit, the presence of adults or nymphs in the crop itself is enough to trigger an insecticide spray.

Border sprays are sometimes sufficient for limiting damage, unless the pest has become established in the crop. Begin management with border sprays at first adult (in crop) find, or whole orchard sprays with first nymph find prior to 1 August. The majority of late season injury appears to occur within the first 30 m of wooded edge. Keep in mind that sprays will only control those BMSB that are present at the time of application, or shortly thereafter, and nymphs are easier to kill than adults. Residual activity is typically limited. New waves of adults can migrate into crops from adjacent areas through the season. Managing BMSB requires season-long attention.

There are no organic insecticides registered for management of BMSB in Canada. Research on strategies for organic producers, including barriers, biological control, trap crops and insecticides is ongoing in the US, where populations of BMSB are present in crop production areas.

Most BMSB in Ontario have been found by homeowners, and in some locations, multiple reports indicate that local populations have been established. To date, BMSB has been confirmed in:

  • Golden Horseshoe and GTA: Hamilton (2010, established population), Beamsville (2014, adult in a trap July 15th, 2014); Burlington (2012), Milton (2012), Toronto (2012), Vaughan (2013), Niagara-on-the Lake (September 2013), St. Catharines (April 2014, photo only; nymph on landscape host July 15th, 2014), Niagara Falls (winter 2014, photo only), Fort Erie (February 2014), Stoney Creek (February 2014); Waterdown: Adults collected in traps July 1st 2014; St. David's: Adults collected in traps July 8th 2014.
  • Western Ontario: Cedar Springs (2013), Windsor (2013, 2014), Kincardine (2013), London (October 2013; established population July 18th 2014), Kincardine (November 2013), Paris (January 2014), Tecumseh, Maidstone (April / May 2014)
  • Eastern Ontario: Newboro (2012, established population), Ottawa (March 2014); Newboro: Adults collected in traps first week of July 2014

If you think you may have found BMSB, please let us know! Confirmed reports help get track BMSB. Call or email the Agriculture information Contact Centre 1-9877-424-1300 or

The research team conducting surveys in crops and landscape hosts across southern Ontario (Cynthia Scott-Dupree, University of Guelph, Tara Gariepy, Agriculture and Agri-Food Canada, Hannah Fraser and Tracey Baute, OMAFRA) have set up pheromone traps for BMSB at over 50 sites in 2014. Many other staff and students are helping with the effort.

For more information:
Toll Free: 1-877-424-1300