The bugs get their name for the pungent smell they emit when frightened, disturbed or crushed.
Ah, the sure signs of fall are here: gorgeous leaves, football games, brisk hikes, and ... stink bugs.
In what's becoming an annual ritual, the smelly, annoying scourge of homeowners from coast-to-coast are crawling inside homes across the country this fall as the weather cools off.
"Stink bugs move indoors in late September and early October," explains Russ Horton, entomologist with pest control company HomeTeam Pest Defense in Dallas. "They go into hibernation during winter and emerge in early spring." They like hiding in attics and inside walls.
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The pests, known officially as brown marmorated stink bugs, have been spotted in 38 states, up from 33 last year, the U.S. Department of Agriculture reports. The five new states since last year are Missouri, Kansas, New Mexico, Texas and Idaho.
They actually came to Texas late last year on the R.V. of a couple who had been camping in Pennsylvania, according to reports from HomeTeam Pest Defense.
Stink bugs get their name for the pungent smell they emit when frightened, disturbed or crushed.
The Mid-Atlantic remains ground zero, though, with the worst infestations in Pennsylvania, New Jersey, Delaware, Maryland, West Virginia, Virginia and D.C., according to USDA data. For instance, 59% of D.C.-area residents say they've experienced a problem with the smelly pests, compared with the national average of 21%.
"The Mid-Atlantic experienced long periods of sustained hot weather this summer, allowing stink bug populations to grow to much higher levels than we saw in 2011," explains Jim Fredericks of the National Pest Management Association (NPMA). "Now that the weather is cooling off, there are more stink bugs seeking sites to overwinter."
Scientists agree: "We're seeing a major increase in their populations," according to USDA entomologist Tracy Leskey in Kearneysville, W.Va., who adds that the unusually warm stretch of weather has allowed two separate generations of the bugs to breed this year.
"Stink bugs do not pose serious property or safety threats to homeowners, but their tendency to invade homes in high numbers can be a nuisance," says Missy Henriksen, NPMA spokeswoman.
"I've seen homes infested with hundreds, if not thousands of them," reports entomologist Kim Reynolds of HomeTeam Pest Defense, who says the company is getting an uptick in calls about stink bugs in recent weeks.
Although a nuisance to homeowners, the odiferous insects pose a much bigger threat to agriculture: "They aren't picky eaters," Leskey says, noting they eat crops such as apples, peaches, corn, peppers, tomatoes, grapes, raspberries and soybeans. This is why the USDA is involved in reducing or eradicating the pests, which unintentionally came to the USA from Asia back in the 1990s.
"Stink bugs do have natural predators, but they haven't kept up with the size of the stink bug populations," she says. "There are many more stink bugs than predators."
Research continues into how a tiny parasitic wasp from Asia could help reduce the stink bug population, Leskey adds. The wasp, which remains under quarantine in research labs here in the USA, only attacks stink bug eggs.