The Environmental Protection Agency said Tuesday (March 1) that it was seeking to cancel registration for a key insecticide used to combat crop-hungry pests such as fall armyworm and corn earworm.

At issue is flubendiamide, an insecticide commonly known as Belt, made by Bayer Crop Science. It’s also known as Tourismo, labeled for tree fruits and grapes, and Vetica, labeled for strawberries and squashes, made by Nichino America. The insecticide has been labeled for use in more than 200 crops, including row crops, pistachios and oranges.

Last month, the EPA asked two manufacturers to voluntarily cancel uses of four pest control products containing flubendiamide, including Belt.

The move follows a Jan. 29 effort by the EPA to get Bayer and Nichino America to voluntarily cancel registration for the insecticide, which was rejected. In response to the EPA’s request for voluntary cancellation, Bayer issued a statement Feb. 5 explaining the company “believes the methods used by the EPA exaggerate environmental risk and would deny farmers access to a critical pest management tool.”

Gus Lorenz, Arkansas Extension entomologist, said Belt is currently the “go-to” product for controlling caterpillar pests in soybeans and other crops.

“It’s been the major product used for control of soybean caterpillars for a long time. So mole worms or corn ear worms, and soybean loopers, the army worm complex — all those pests, we use Belt for control."

The EPA initially issued a temporary registration for Belt in 2008, which was contingent on the findings of long-term studies on any adverse effects of the insecticide. According to the Tuesday EPA statement, several studies indicated the product may be toxic to benthic invertebrates, part of the aquatic food chain.

Out of reach

Lorenz said the second most commonly used insecticide to control caterpillar pests in crops is Prevathon, a DuPont product. Both Belt and Prevathon belong to the diamide class of insecticides, a fact that Lorenz said may put both out of reach for growers in the state and elsewhere.

“It only stands to reason that if there’s an issue with Belt, there might be a similar issue with Prevathon,” Lorenz said. “Between the two products, you can account for about 90 percent of efforts to control caterpillars in soybeans, as well as grain sorghum, corn, and to some degree, cotton.”

Lorenz said the current label for Belt is still active, and the product is legal to use in Arkansas. If both Belt and Prevathon become illegal or unavailable, growers will still have access to several other insecticides that can control caterpillars, Lorenz said, although none of them are known to be as effective.

“We have a limited number of insecticides that are still reasonably effective for control of caterpillar pests,” Lorenz said. “But these two products are extremely efficacious, and have longer residual control than most of the other products currently available.

“There’s a reason why they’re the product of choice. It’s because they’re very safe, with low mammalian toxicity and not toxic to off-target organisms, specifically us,” he said. “There’s been no impact on honey bees, and other than the benthic organisms, there’s been very little indication that there’s any off-target issues.

“We don’t have any other products outside that class that provide quite that level of control. So that’s a big concern,” Lorenz said.

For more information on pest insect management, contact your county Extension office or visit www.uaex.edu.