Hello, Harford County!
The warm days of spring are upon us—and now so are the stink bugs! Like many others I know, my house was the perfect overwintering site for many of these little critters who are now waking up and getting ready to march back into the fields.
Stink bugs have been a pest of concern to farmers and homeowners alike. Many are wondering if 2013 will be a mild year, like 2012 was, or if we should prepare for another year like 2011 or 2010.
I had the opportunity to attend a regional Brown Marmorated Stink Bug (BMSB) Conference in April, where researchers from USDA and several Mid-Atlantic universities presented their findings. Although there is still more to be done, the past few years’ work has yielded some enlightening results.
Are traps effective? Most traps that are currently available use a pheromone from a different species of stink bug to attract BMSBs. In research trials, traps containing this pheromone were only effective in late season (after mid-August). Researchers have identified and successfully synthesized a BMSB-specific pheromone, which has proven to successfully attract BMSB all season. However, it will not be available commercially until 2014.
Another research study showed that fields with traps had significantly more damage than fields without traps, even though the traps did catch a large number of BMSBs. This is likely because the pheromone actually attracts more BMSBs into the field. Thus, it may be advisable to locate traps in a “sacrifice area” in order to contain damage to one spot. This will also make it easier to treat with pesticide since most of the BMSBs will be congregated in one area.
What pesticides are effective? Per laboratory research conducted by University of Maryland Department of Entomology, several commercially-available pesticides exhibited significant control activity when direct-sprayed onto BMSBs: insecticidal soap, carbaryl, horticultural oil, acetamiprid, and permethrin. Significant control via contact with dry residue was achieved only using acetamiprid and permethrin. No significant control was found using neem oil, spinosad, herbal essential oils, or capsaicin. Field trials are still needed to support these results.
How can I keep them out of my house? As many of us know, BMSBs overwinter in homes. (Recent research proves that they also overwinter in standing dead oak and locust trees.) The bugs we see inside now entered in the fall, were dormant through winter, and are becoming active now in response to warmer temperatures. The key to keeping your home BMSB-free is to prevent an influx when the bugs are looking for places to overwinter. Scout your yard for trees and shrubs that attract BMSB; researchers have identified several favorites. Remove or treat these specific host plants in the fall. The idea is to keep BMSBs away from your home, during the fall, until they have found another place to overwinter.
Finally, to answer the question or this year’s infestation level—get ready for a challenge. Six times more BMSBs went into overwintering in 2012 than did in 2011. Hopefully what science has taught us will help us protect this year’s crops!
Best of luck for a safe, successful season,