The Oregon Department of Agriculture is taking additional steps to protect bees and other pollinators from exposure to specific pesticide products following multiple incidents of bee deaths this summer. In adopting a temporary rule, ODA is prohibiting the use of pesticide products containing the active ingredients dinotefuran and imidacloprid on linden trees or other species of Tilia.

The rule applies to all users, including professional applicators and homeowners.

“Although we took significant steps last year to restrict the use of these pesticide products, we’ve seen more cases involving bumblebees attracted to blooming linden trees and pesticide applications,” says ODA Director Katy Coba. “In order to protect our pollinators, we feel it’s important to adopt additional restrictions.”

Last year, based on high profile incidents of bee deaths, ODA adopted a required label statement on pesticide products containing imidacloprid and dinotefuran prohibiting the application of these products on linden trees and other Tilia species. For 2014, newly-labeled products distributed into Oregon are required to state the restriction. Products with pre-2014 labels are still in commerce and, prior to the temporary rule, could be used when plants were not in bloom. Two recent incidents of large bee deaths– one in Eugene, the other in Beaverton– involved the use of imidacloprid products with an older label, which alerts the user that the product is “highly toxic to bees exposed to direct treatment or residues.” To address confusion or misunderstanding caused by having two different label statements, ODA is simply prohibiting the application of any product containing imidacloprid or dinotefuran on linden, basswood, and other trees of Tilia species.

Failure to comply with the new rule could result in license suspension or revocation as well as imposition of a civil penalty.

The temporary rule, which goes into effect immediately, will be enforced for 180 days and will protect pollinators while allowing ODA to complete its investigation of recent bee death incidents as well as determine any future regulatory actions.

ODA is contacting all pesticide license holders in Oregon regarding the new rule and will continue to provide outreach and education on pollinator protection. Additional information can be found on the ODA website at