DAN GILREIN COURTEYS PHOTO | Stink bugs likes all plants; and peaches, apples, plums, cherries and blueberries are some fruits they favor.

Calverton farmer Howard Lewin can handle potato bugs; he fought back with flamethrowers when the pest infested his 70 acres of spud back in the late 1970s.

Brown marmorated stink bugs, insects originally from Asia that are now destroying acres of cropland in Maryland and Pennsylvania, are Lewin’s new worry, especially if their population on the East End reaches the numbers reported further south.

And that could soon be the case. Suffolk County is poised for a stink bug infestation, said Daniel Gilrein, an entomologist with the Cornell Cooperative Extension in Riverhead.

Mounting evidence shows there are established populations of the insect in Nassau County, and alarming numbers of the pest were found in a Fort Salonga home, Mr. Gilrein said. The growing population means the East End could be next — if not this year, then in the next few.

“It will be a problem when they come and establish in Suffolk,” Mr. Gilrein said. “The effects will be different depending on who and where you are.”

A tractor driver in Calverton last month was the first to spot one of the bugs on the East End, Mr. Gilrein said. A single bug, identified from other, less harmful pests by its white-spotted antenna, may mean more are coming to feast on their favorite foods such as tomatoes, peppers, berries and apples. The brown marmorated stink bug proliferates easily in the U.S. because it has no natural predators here, Mr. Gilrein said.

Stink bugs are nuisances for homeowners, Mr. Gilrein said. They don’t irritate skin like bed bugs, and don’t damage houses like termites. But they can leave dark marks on the leaves of ornamental landscaped plants, according to a fact sheet from Cornell.

For homeowners with small gardens, Mr. Gilrein recommends brushing the bugs off plants into bowls of soapy water — when they’re squashed, or even threatened, they expel the odor that gave them their name.

Covering plants with protective netting or screens works too, but only lasts for a short period of time, he said.

Another concern for homeowners is the bug’s wintering habits – they invade houses and other buildings in the late summer and early fall for shelter from the cold, Mr. Gilrein said. To protect against the unwelcome visitors, homeowners should seal any small cracks or crevices in siding, walls or door or window frames, he said.

Sherry Brezinski, the nursery manager at Talmage Farm Agway & Garden Center in Riverhead, has not had any home gardeners complain to her about the pests, at least not yet. She thinks she may hear more about the problem in the fall, when the bugs move indoors.

Mr. Brezinski suggests leaving the bugs alone or spraying them with an insecticide. Some beetle killer products will eliminate the pest, she said.

Anyone who suspects they found a stink bug can drop it off at Cornell’s diagnostic lab on Griffing Avenue in Riverhead, Mr. Gilrein said.

Stink bugs pose a much greater threat to farmers, as they can severely impact their livelihoods. As the bugs feed, they leave deep brown marks that may be mistaken for rot, making crops unmarketable.

“I guess I’ll just have to use a stronger insecticide,” said Jonathan Sujecki, who farms 105 acres in Calverton and is concerned about protecting his tomato crop from a stink bug invasion.

Farmers can use insecticides to combat the pest, but even those become ineffective if the population skyrockets to high levels, Mr. Gilrein said.

But the area’s organic farmers are practically defenseless against the winged invaders – few pesticides are approved for use by organic farmers, Mr. Gilrein said. Products that contain natural pyrethrins, a type of pesticide, work, but only for a very short period of time, he said, adding that those chemicals can’t control large numbers of stink bugs.

Crop covers are another option for organic farmers, he said.

Less than five percent of Long Island farms are organic, according to Long Island Farm Bureau officials.

Anthony Panarello, who owns Natural Earth Farms in Calverton, is one of the organic farmers. He worries about the pest’s effects on his 30,000 to 50,000 pounds of peppers, tomatoes and eggplants he sells each year wholesale.

“I’m concerned about what it would take to control the bug,” Mr. Panarello said.

Mr. Gilrein and the Cornell Cooperative Extension are closely monitoring any potential stink bug population on the East End.

Researchers have so far set up traps to catch the bugs and are working with entomologists in Upstate New York to monitor an expected invasion, a collaborative effort called the Eastern New York Brown Marmorated Stink Bug Project.

When confronted with the possibility of a stink bug infestation, farmers like Mr. Lewin and  Mr. Sujecki griped it would be yet another issue on their lengthening list of problems, like hot weather and cucumber bugs.

But “it’s a bit more serious than their everyday problems,” Mr. Gilrein said.