The landscape company that accidentally killed an estimated 50,000 bees with an insecticide application in Wilsonville, Ore., last spring may not have applied the product off-label, according to a state inspector investigating the incident.
Mike Odenthal, a pesticide investigator with the Oregon Department of Agriculture, said that instructions on the insecticide that killed the bees prohibit applications during bloom when bees are present.
The linden trees sprayed in a department store parking lot June 15 were in bloom, Odenthal said, but it is not clear whether bees were present.
“There may not have been any bees present at 6 a.m. when they made that application,” Odenthal said.
He added that evidence to date suggests that the workers involved did not knowingly spray the neonicotinoid insecticide Safari off-label.
“They didn’t set out to break the rules,” Odenthal said.
The crew was targeting aphids in the application that led to the bee deaths, Odenthal said. Aphids are included on Safari’s label.
Odenthal would not release the name of the landscape company.
The June 17 discovery of the bee kill in the Wilsonville parking lot drew national attention and further focused interest on the effects of neonicotinoid insecticides on bees. The insecticides have long been thought to be a contributing factor to colony collapse disorder, which has led to a dramatic decline in bee populations in recent years.
After the discovery, ODA Director Katy Coba placed a six-month moratorium on all outdoor use of pesticides containing the neonicotinoid dinotefuran, the active ingredient in Safari. The moratorium expires Dec. 24.
The EPA in August added labeling requirements to strengthen protection for bees on some neonicotinoid pesticide products, including products containing dinotefuran, imidacloprid, thiamethoxam and chlothianidin.
The new labels, required by early 2014, are similar to the product’s former labels in that they prohibit application when bees are present, but they include additional language intended to minimize the products’ exposure to bees.
The new labels also include a bee advisory box with information on routes of exposure and spray drift precautions, said David Stone, director of the National Pesticide Information Center at Oregon State University and an assistant professor in the university’s Department of Environmental and Molecular Toxicology.
Stone characterized the label change as significant.
“This is a big label change,” he said. It could affect everything from the way trainers address the pesticides when conducting pesticide credit recertification courses to how and when the products are applied, he said.
Odenthal said more label changes could be introduced in coming months that further refine protections for bees.
“There is a lot of activity at the national level about how to make the label restrictive enough to protect bees, and not make it so restrictive that you can’t get anything done with them,” he said.
Odenthal said the department intends to wrap up its investigation into the Wilsonville bee kill by the end of the year.
The company faces fines and a possible suspension of their pesticide applicator license if it is found to have applied Safari in violation of the product’s label.
“By that time, we’ll have an opinion about whether or not bees were there at the time of the application,” he said.