There is some hope in sight for Virginia fruit growers as the peak of stink bug season approaches: temporary approval of a highly toxic insecticide.

The Environmental Protection Agency has approved the sale of Dinotefuran in Virginia to help protect hard-hit apple and peach crops from the voracious appetites of the brown marmorated stink bug. Without it, experts and state officials said, the state would face another year of potentially devastating economic damage.

The Virginia Department of Agriculture and Consumer Services asked the EPA for a temporary exemption from Dinotefuran restrictions for certain fruit crops, which the federal agency granted June 29. Growers will soon be able to use the product to help protect crops of apples, pears and peaches from the stink bug, which gets its name from the gag-inducing odor it emits when crushed. The exemption lasts through Oct. 15, considered the end of the harvest season.

The insecticide has been approved for use on crops such as melons, grapes and certain vegetables but not for other types of fruit because of its unknown environmental effects, said Christopher Bergh, a Virginia Tech associate professor of entomology.

“Apples and peaches were both heavily impacted last year [by stink bugs], in some areas more than others,” Bergh said.One benefit of Dinotefuran is its short “pre-harvest interval,” Bergh said, meaning that the insecticide can be safely applied to fruit up to three days before harvest.

“For that reason, we are recommending its use particularly later in the season, when the brown marmorated populations tend to be highest . . . and feeding rather aggressively on fruit as they’re maturing,” Bergh said. “It’s a good fit for those days and weeks immediately preceding harvest.”

As part of the exemption, the EPA issued guidelines for using Dinotefuran to mitigate unintended impact on the ecosystem, including the insecticide’s toxicity to honey bees, state agriculture officials said.

Rep. Frank R. Wolf (R-Va.), who hosted a forum in Loudoun County in April, during which he heard concerns about the rising stink bug population, said in a statement that the state’s agriculture community will benefit from the EPA decision.

The EPA’s approval follows the recent passage of an appropriations bill by the House of Representatives requiring the U.S. Department of Agriculture to make the fight against stink bugs a priority. That measure directs the agency’s in-house research divisions to identify and develop methods to control the stink bug population. The bill awaits Senate consideration, Wolf’s statement said.

Tyler Wegmeyer, who owns Wegmeyer Farms in Hamilton and is a director of congressional relations for the American Farm Bureau, said the bugs contributed to the loss of more than 50 percent of his raspberry crop last year.

“Most farmers in this area have never seen anything like this,” he said of the infestation. Farmers have a better understanding of most other seasonal pests and can anticipate their arrival. “But with the stink bug, it feeds on anything, so it may be feeding in a swarm somewhere and then during the night, all of a sudden, it comes and takes over your raspberries. If you’re not out there, scouting multiple times a day, you can be really hurt by it.”

On his farm, Wegmeyer saw the results of the stink bugs’ unpredictable and voracious appetite in half-eaten fruit and pocked tree leaves. Wegmeyer said he has spoken to farmers throughout the region who were dealt similar blows by stink bugs — particularly those who grow apples and peaches.

Scientists and farmers alike say they are bracing for a peak stink bug population next month and in September, with numbers comparable to last year’s. Although it’s early in the season, Bergh said, some Northern Virginia farmers have already reported significant damage to peach and apple orchards.

“People are starting to see them now, and I’m starting to see them, as well,” Wegmeyer said. “I think everyone’s preparing for at least the same amount of loss as last year, if not more this year.”

Wegmeyer said Dinotefuran might help prevent comparable losses this year, but what is really needed is a long-term strategy for dealing with stink bugs.

“It’s great that these products have been released for use — that’s another tool that farmers can use to combat the stink bugs — but there is so much unknown about this bug,” he said. “There just isn’t enough research yet. We have to understand it better.”

Besides inflicting considerable damage on crops, the insects were a nuisance for homeowners, as well, with swarms of bugs covering windows, walls and screen doors.

Bergh said new products targeting stink bugs should be on area hardware store shelves and other retail outlets by the time that the peak population occurs in the fall.

“A problem of this magnitude invites the entrepreneurial spirit,” he said. “There are products that are going to be made available . . . such as various kinds of traps designed for use by homeowners. ”

Meanwhile, research on a stink bug solution continues.

“We’re still very much in the steep part of the learning curve, the growers as well as the research community,” Bergh said. “At the end of the season, we’ll be able to sit down and look at everything as a whole and see if we can come to better grips with [the problem] before the 2012 season.”