Coming soon to you . . . the brown marmorated stinkbug or if you prefer, Halyomorpha halys. The Asian invader was initially confirmed from Allentown, Pennsylvania in 1996. Since then it has been identified in 33 other states.
Last February, Jennifer Llewellyn and Hannah Fraser wrote in trade periodical Horticulture Review February that “these pests have not been detected in Ontario, but we can’t help but worry that they might occur in the not-so-distant future.” Six months later, their fears have been proven well founded. The brown marmorated stinkbug has officially been identified from an undisclosed location in Ontario.
While there are other species of stinkbug in the province, H. halys hales from China, Korea, Japan and Taiwan. In its native habitat is kept in check by various predators. Unfortunately, none of these is to be found in North America – yet. In China, the parasitoid Trissolcius halyomorphae is a primary predator on stinkbug eggs. Safety tests are underway in the United States but it will be at least two more seasons before it might be introduced. Meanwhile, as Catherine Zuckerman observed in National Geographic, it smells like trouble.
She is right. Stinkbugs are appropriately named. Squashed, they release a repulsive odour that deters birds and other predators. It is also highly offensive to humans who slam a fist down on a specimen found overwintering indoors. Fortunately washing with soap and water eliminates the stench.
In the U.S., female stinkbugs are capable of laying four broods of eggs a year, between 20 and 30 eggs at a time. Outside, they overwinter under fallen timber and in leaf litter. But they are also equally adept at finding shelter under building siding or indoors, in private houses, apartment and office buildings.
If all this isn’t bad enough news, they are a serious pest of vegetables, fruit and ornamental plants. According to Llewellyn and Fraser, commercial growers in the U.S. are finding fruit losses in the neighbourhood of 20-50 per cent.
Even where chemical sprays are permitted, the brown marmorated stinkbug is resistant to them. Applications at weekly intervals reportedly barely control the pest.
Online, in the U.S. claims have been made for both homemade and commercial traps as an alternative. In most instances, since almost all refer only to “stinkbugs,” it is difficult to determine if it is H. hales or instead native stinkbugs that these traps eliminate. Plow and Hearth (800-484-7544) offers RESCUE!®, an American-made, odor-free, reusable non-toxic stinkbug trap for US $19.95. It comes with a two-week supply of attractant (7-week refills $9.95). It emits a pheromone attractant that draws stinkbugs from within a 20-foot radius. Once inside, they dehydrate for easy disposal. Flushing down the toilet appears to be the recommended method.
A somewhat different but similar trap from another U.S. company was independently tested. They were found virtually useless in this past cold, wet spring but, in all fairness, they are recommended for the warmer weather of summer and early fall. Indoors, use a vacuum to suck up the pests and dispose of, as mentioned above, down the toilet.
Unfortunately, whatever else, this new pest is clearly a little stinker.
Wes Porter is a horticultural consultant and writer based in Toronto. Wes has over 40 years of experience in both temperate and tropical horticulture from three continents.
