Stink Bugs In WA: How To Stop Them Before They Smell Up Your Home

WASHINGTON — An odoriferous brigade of brown marmorated stink bugs is crawling into houses all over Washington right now, just itching to set up a winter camp in your warm, cozy abode.

You’ll recognize these shield-shaped insects by their marbled or streaked — marmorated — appearance. We’ll get to what you need to do to stop their invasion in a bit — and you’ll want to, because they’ve earned their common name — but more important is the significance of their spread to 47 states, including Washington.

Stink bugs are voracious eaters. What they can do with those piercing, sucking mouthparts (sounds wicked, doesn’t it?) to an apple, peach or pear orchard isn’t pretty. Lots of other crops are at risk from stink bug damage, too.

Stink bugs, which likely hitched a ride to the United States from Asia in a shipping container, have caused severe agricultural and nuisance damage in a dozen states, mainly those in the mid-Atlantic region, but also in Michigan and Oregon. Another dozen states report agricultural and nuisance problems; a handful report nuisance problems only; and a couple of states haven’t seen any stink bug activity.

Here in the Evergreen State, recurring stink bug populations are known to be in at least 29 counties and present agricultural and nuisance problems, but below the more severe levels seen in states like Oregon and much of the East Coast.

The Washington Invasive Species Council writes of stink bugs:

"It will attack a large variety of plants — more than 170 species — including many fruits and vegetables. It leaves small necrotic patches on any plant matte it eats, rendering produce inedible. Homeowners likely will notice an invasion before anyone else, because the brown marmorated stink bug initially will attack vegetable gardens and landscaping plants, and will spend the winter in homes and other human-made structures."

To stop further infestations, some of the hardest-hit states have introduced samurai wasps (Trissolcus japonicus) that come from the same part of the world as stink bugs. They hitched a ride to North America, too, likely emerging from stink bug egg masses.

The wasp, which is about as big as a sesame seed and lays its eggs into the eggs of stink bugs, is proving to be a promising biological control agent against brown marmorated stink bugs, according to Michigan State University entomologists.

In Washington, officials recommend using pheromone and light traps instead of pesticides, which can have collateral damage for helpful species like ladybugs. Residents can also report stink bug sightings to the state online.

26,000-Strong Stink Bug Invasion

Not every homeowner has a stink bug horror story like that of Pam Stone and Paul Zimmerman, who discovered that 26,000 stink bugs invaded their home as the cool air of fall came to South Carolina. They had left doors open leading to a second-story deck outside their bedroom, and the stink bugs marched right in as if they owned the place.

The couple’s experience, hilariously recounted by Kathryn Schulz in The New Yorker, was “like a horror movie,” Stone said.

They were on every visible surface, and on many that weren’t visible. Squashing them wasn’t the answer, of course, because it’s when they’re threatened that stink bugs throw off that gawdawful smell. But when the couple carried some outside, more stink bugs flew in.

Finally, after 45 minutes, they thought their DIY extermination had worked. Nope. They heard one buzzing as it flew across the room to join its cronies hiding on the backside of a picture.

This went on for days, with Stone and Zimmerman finding them in the strangest places.

Stone, who is an actress, comedian and horse trainer, sprang off her horse as if she’d been catapulted when she discovered her saddle was crawling with them.

Your home may not be invaded by a horde of tens of thousands of stink bugs, as Stone and Zimmerman’s was. But a wildlife biologist in Maryland, entomologists in Virginia and bank employees in West Virginia reported larger infestations — about a million in one place, according to one estimate — of the shield-shaped menace, The New Yorker report said.

Scared yet?

If you like to eat, you should be.

When stink bugs feed on crops, damage can include everything from bruises and blemishes to aborted sweet corn kernels and a change in the sugar levels in some fruits.

Stink bugs damage ornamental trees as well as fruits and vegetables, and they pose such a threat that the U.S. Department of Agriculture funded the Stop the Brown Marmorated Stink Bug strike force. It's a team of 50 researchers from 18 land-grant universities closely tracking the migration of the invasive, fast-moving pest.

Stink Bug Control Tips

On the home front, your best defense against stink bugs is to arm yourself with weather stripping, caulking and tape, and make your home a fortress. Seal up gaps and crevices around foundations and any area where doors, windows, chimneys and utility pipes are cut into the exterior. Any opening large enough for a stink bug to crawl through should be sealed.

The best thing to do if you find them inside is gently sweep them into a bucket, then fill it with a couple of inches of soapy water. You could vacuum them up, but perhaps do that as a last resort because it will trigger stink bugs’ notorious odor and make your vacuum cleaner smell nasty.

Some companies recommend a special stink bug vacuum — a cheap, handheld model used only for that chore. The bag should be tossed in a thick, disposable trash bag and taken far from the house.

Poison can quickly kill the stink bugs, but that will also trigger their stench. Professional extermination is another option.

Or, Just Live With Stink Bugs

Or, if you can bear the thought of living communally with stink bugs inside your home, you could just leave them alone.

Their piercing, sucking mouthparts — tiny shields about a half-inch long and wide, which they curiously tuck between their legs when they’re not piercing and sucking the juice from plants — are not good for biting people. Stink bugs can’t sting you.

They don’t nest or lay eggs or reproduce. They don’t feed on anything or anyone in your house. They just move in to take a load off for a few months — scientifically, they enter a dormant phase known as diapause.

You’re unlikely to even know they’re there unless you do something to disturb them. And then, look out. Pee-yew.

But if you just leave them alone, they’ll crawl right back outside in time to take a bite out of your garden, and the war on stink bugs will begin anew.