Sarah Taddeo

@sjtaddeo

(Editor's Note: This story has been updated from a 2014 article published on stink bugs.)

What crawls on six legs, stinks to high heaven and makes its way across America state by state?

The answer is brown marmorated stink bugs, which have been showing up in new states every year since their introduction as an invasive species from Asia in the late 1990s.

This particular species of stink bug has been congregating on window screens and fruit crops in Monroe County for the last three to four years, and the population is increasing, said Cornell Cooperative of Monroe County Extension Horticulture Program Leader Walt Nelson.

The bugs are about a half inch in length, have wings and will emit a foul odor if you threaten or squish them, he said.

Chun Li of Pittsford found stink bugs sitting along her new home's window jams when cold weather came last year.

"I found a few and just picked them up and got rid of them," Li said. "Then I pulled back my curtains and found 10 more."

While most Rochester residents might find five to 10 stinkbugs in the house at one time, Li found enough insects to call in the exterminator.

"There were at least 30 in every room, mostly around the windows," she said. "It was really terrible."

Stink bugs have gotten worse this year, said Philip Burger of Rochester Exterminating. He started dealing with them in the last few weeks, as the critters want to get out of cold weather and into warm homes.

"The worst ones I've seen are more in the city area," he said. "Those houses are typically older and taller, and have a lot more places where (stink bugs) can enter the structure."

Rochester Exterminating uses a combination of liquid and dust insecticides to fight stink bugs in and around homes. Residents should seal cracks and crevices around door jams and windows with caulk, and many everyday insecticide brands are coming out with products that list stink bugs among other targets, said Burger.

Stink bugs showed up in Mid-Atlantic states such as West Virginia and Maryland first, and have now spread across the country, including Hawaii, said research entomologist Tracy Leskey of the U.S. Department of Agriculture.

"This has been devastating for growers in the Mid-Atlantic," Leskey said. Stink bugs will enter Mid-Atlantic homes by the thousands — one home had over 26,000 inside, she said.

Monroe County is both agricultural and residential, and may see an increase in stink bugs in the coming years, said Nelson.

Here are 10 things to know about the little brown stinkers.

• 1. They're not from around here.

Brown marmorated stinkbugs are native to Japan, China and Korea and were accidentally imported to the Allentown, Pa., region in the late 1990s. They have no natural predators in the U.S.

• 2. They're multiplying.

They've spread to 42 states in 2015, up from 39 states in 2013 — the new states are Arkansas and Hawaii. They were found in New York in 2010.

• 3. They really stink.

People have described the smell as anything from skunk to dirty socks to coriander — "We don't recommend smashing them, because then you'll find out why they have their name," said Cornell Cooperative Consumer horticulture educator Karen Klingenberger.

• 4. They're ruining agriculture.

Six states in the Mid-Atlantic reported "severe nuisance and agricultural damage" in June 2014, with farmers reporting total losses of tomato, apple and corn crops in 2013, said Leskey.

Nelson described the stinkbugs' effect as "scabs" and bruising on fruit and vegetables. Monroe County's crop yield isn't severely affected, but crops like garden vegetables and apples may have some aesthetic damage, he said.

Cornell Cooperative is working with New York farmers to deal with the problem using pesticides during summer growing seasons, said Nelson.

• 5. They find creative ways into houses.

If there are cracks in screens, door jams, roofs or walls, stinkbugs will find them, said Klingenberger — "they're all trying to get into our houses and spend the winters with us," she said. To make your home stinkbug-proof, check around windows and doors for small openings, both indoors and outdoors.

• 6. They like plants.

If you live near a wooded area or have a vegetable garden, your home may have a higher risk of stink bugs, said Miller. If you have potted plants in your home, that's where stink bugs might congregate.

• 7. They won't bite you, harm your pets or ruin your carpet.

Stink bugs don't pose any danger to humans or animals, and won't destroy indoor non-plant material, Nelson said. "If a pet eats a stinkbug, they'll probably spit it out after the first bite," he said. The bugs just want a warm window where they can sun themselves.

• 8. Vacuum them at your own risk.

Vacuuming stink bugs makes for a quick and clean disposal, but your vacuum might not smell so great afterward, said resident Veronica Miller of Irondequoit, who dealt with a few indoor stink bugs this year.

• 9. You can buy or make stink bug traps.

Stink bugs like light and they can't swim, so a desk lamp with a tub of soapy water underneath it works as an impromptu stink bug trap. You can also buy lighted stink bug traps at local hardware stores.

• 10. If all else fails, call an exterminator.

Ray Miller said exterminators can spray the exterior of a severely infested house with chemicals that kill insects on contact. Exterminators sprayed Li's home in Pittsford, and she said she hasn't seen a stink bug since. While there are products on the market that can legally be used against stink bugs inside the home, their use is not recommended by Cornell Cooperative Extension, Nelson said.

STADDEO@DemocratandChronicle.com

Twitter.com/sjtaddeo

Got stinkbugs? Here's how to learn more about them

Call the county: To hear about how stinkbugs might be affecting crops or homes in Monroe County, call the Cornell Cooperative Extension of Monroe County at (585) 753-2550.

Call the exterminator: Area exterminators such as Terminix, at (585) 349-0099, or Envirotech, at (866) 513-2884, can offer more information about how to keep stinkbugs out of the house and how to kill indoor populations.

Read more: To read more about how stinkbug populations are growing nationally and what is being done to stop them, go toStopBMSB.org, hosted by the U.S. Department of Agriculture.