EPA, WSDA approve new wireworm seed treatment

Last week, the Washington Association of Wheat Growers (WAWG) and the Washington Grain Commission (WGC) received word that their support for a new wireworm seed treatment had been successful.

Teraxxa, manufactured by BASF, was approved in mid-January by the Environmental Protection Agency for use in 2021, just in time for spring seeding. The Washington State Department of Agriculture (WSDA) approved the label shortly after.

“This is great news for Washington wheat growers who are fighting against wireworms,” said Ryan Poe, WAWG president and a grower from Grant County. “Farmers have very few options against wireworms, a pest that can cause significant yield losses. We appreciate the actions by the EPA and the WSDA to complete registration of Teraxxa.”

In December, WAWG and the WGC sent a letter to the EPA supporting an emergency exemption (Section 18) for Teraxxa. The letter states that “…growers need a new seed treatment that controls wireworms (causes mortality) rather than suppresses populations during the early season. Currently registered products…intoxicate wireworms but do not consistently kill them. They survive and reproduce, leading to increasing populations and damage.”

According to BASF, the active ingredient in Teraxxa seed treatment, broflanilide, is a new class of chemistry that delivers a new mode of action to protect against wireworms. Broflanilide binds to the wireworm’s central nervous system causing hyperactivity of nerves and muscles, which ultimately eliminates the pest altogether. Trials show it to be highly effective with rapid wireworm mortality on contact across all species and life stages, with field studies showing 80 to 90 percent reduction in wireworms. See BASF’s announcement here.