Hannah Fraser, Entomology Program Lead — Horticulture, OMAFRA, Vineland
From ONvegetables in The Grower, February 2013
The brown marmorated stink bug (BMSB) is an invasive alien species native to China, South Korea, Taiwan and Japan. It was most likely introduced to North America in the mid 1990s, and was first positively identified in Allentown, Pennsylvania in 2001. While BMSB is capable of natural spread, the pest is also an excellent hitchhiker and can be moved over large distances in cargo and vehicles. At present it has been found in 39 states and several Canadian provinces, though many of these are simply detections rather than confirmed as established in the field.
BMSB has a very broad host range that includes tree fruit, berries, grapes, vegetables, agronomic crops, ornamental trees and ornamental shrubs. Damage results when nymphs and adults feed on either vegetative or fruiting plant parts. BMSB is well-adapted to a diversity of landscapes and does not require a specific host to facilitate establishment or spread. Patterns of dispersal between hosts during the season are not well understood and contribute to difficulties in managing BMSB. The pest is highly mobile and can readily switch hosts, moving between crops throughout the growing season.
Adults overwinter in sheltered areas that may include homes and other heated buildings. As they can aggregate in very large numbers (up to several thousand where populations have reached severe agricultural level status), BMSB has become a considerable nuisance pest for home owners. Aggregation in artificial structures is not common among stink bugs, and is a behaviour that provides an early warning of where BMSB has become established. Shelter-seeking behaviour contributes to the widespread distribution of this pest through hitchhiking by various means of transportation including cargo, vehicles and railroads.
There have been numerous interceptions of BMSB coming into with goods and vehicles Canada since 1993. Following several homeowner finds from 2010 and 2011, a population of BMSB was identified by OMAFRA during the summer of 2012 in Hamilton, Ontario. Hundreds of nymphs and adults were found in buckthorn located within a wildlife sanctuary and along parts of the Niagara Escarpment. Despite province-wide surveys in 2011 and 2012, BMSB has not yet been detected in crops.
As days chilled down in late September and early October, adult BMSB began to move indoors. Not surprisingly, calls and emails from homeowners started to come in to the OMAFRA Agriculture Information Contact Centre (AICC). Although the majority of specimens were collected in Hamilton, there were over thirty finds scattered all over Burlington, which most likely indicates BMSB is established there as well. Adults were also collected at two locations in Toronto and in Newboro. Homeowners reported finding multiple individuals in gardens and indoors. Information collected from homeowners and the known distribution of BMSB suggest that this pest has been established locally for several years.
The majority of the Hamilton specimens are showing up along the Escarpment. A likely reason for this is because this part of the city is heavily forested, and it contains many of the woody non-crop hosts that BMSB use through the season such as Tree of Heaven, catalpa, maple ash, etc. (and apparently buckthorn). Populations can build up in these unmanaged areas. BMSB tend to become established in urban areas first then disperse to agricultural crops. The abundance of suitable landscape hosts and proximity of BMSB populations pose a serious immediate risk to adjacent agricultural areas in Brant, Halton, Hamilton and Niagara counties. Growers in these areas should be particularly vigilant about monitoring for BMSB.
Three pest control products have been registered for managing BMSB in Canada, with other solutions identified at the National Minor Use Priority Setting Meeting in 2012.
The Canadian Hort Council and Agriculture and Agri-Food Canada’s Pest Management Centre have formed an Invasive Alien Species Coordination Group to facilitate and coordinate pest management research issues and outreach efforts to support the development of mitigation strategies for Canadian growers affected by BMSB (and spotted wing drosophila, another designated invasive). A national technical working group has been established to prioritize research needs, including potential management solutions. There have been considerable efforts in the US to develop monitoring tools, evaluate natural enemies, and screen chemical controls. Knowledge gained from this work will be valuable to growers in Canada.
Management is particularly challenging in organic crops. None of the products registered to date in Canada or the US are options for organic production. Funding for research into the management of BMSB in organic production has recently been made available by the United States Department of Agriculture Organic Agriculture Research and Extension Initiative. Up-to-date information on research into organic management tactics, including trap cropping, can be found at www.stopbmsb.org/managing-bmsb/organic-bmsb-links and http://www.bmsb.opm.msu.edu/.
Early detection is important to the long term success of management programs. We need to have a better understanding of where this pest is and how well it is established. There is a monitoring network for this pest and we hope to conduct surveys in 2013/2014; however, we have a better chance of finding pockets of small populations if more people are actively looking. Tracking the distribution and spread is essential.
Many of those reporting BMSB indicated they’ve been seeing them for 3 or 4 years; they just didn’t realize they were looking at something new. A sample is required to confirm BMSB. For pictures of BMSB and look-alikes, visit www.ontario.ca\stinkbug. If you think you have found BMSB, contact the OMAFRA Contact Centre at 1-877-424-1300 or email email@example.com, and we will provide you with instructions on what to do with the sample. High resolution pictures are useful for identification. For the most recent map (US and Canada), as well as reports and presentations, visit www.stopBMSB.org.