By Diane Dietz, The Register-Guard,


Hundreds of bumblebees are dying in Eugene, and a longtime tree spray company faces investigation by the state Department of Agriculture.

The ongoing occurrence of bee fatalities began Tuesday at the Jacobs Lane Apartments, off Highway 99 in northwest Eugene.

Agriculture investigators took samples of bees, leaves and flowers and are analyzing the die-off; Oregon State University entomologists are on the case.

Glass Tree Care and Spray Service, which sprayed chemicals on 17 linden trees around the Jacobs Lane complex, is cooperating.

“We hold ourselves to the highest business and applicator standards, and take this matter very seriously,” company President J.P. Mischkot said in an e-mail.

Such incidents are of concern to state and federal governments because of a troubling decline in honeybee colonies. Such pollinators are crucial to the food chain, responsible for one out of three bites of food that Americans eat, according to the USDA.

In Oregon, blueberries, apples, plums and peaches are among the crops that need a pollinator to produce fruit.

The state Department of Agriculture arrived at the scene late Wednesday after seeing a television report on the bee die-off. The investigator found 200 to 300 dead or dying bees on sidewalks near the linden trees.

“Most of them were bumblebees, but there were a few honeybees as well,” agency spokesman Bruce Pokarney said.

By Thursday morning, the sidewalks around the trees were littered with bumblebees, honeybees and some ladybugs, arborist and beekeeper Doug Hornaday said.

“You see dead bees all over the place,” he said. “There’s probably 1,000 at least.”

The linden trees are heavy with yellow blossoms. Bees — which remember where the nectar is — can be expected to continue returning to those trees, Hornaday said.

Seeing all the dead bees was bad enough, said Lisa Arkin, executive director of the Eugene-based Beyond Toxics.

“Some of them were quivering and in convulsions,” she said. “It was awful to behold. We didn’t know whether to put them out of their misery or just walk on.”

Arkin said the bee death toll is probably higher than investigators can see.

“We don’t see the ones that flew off 50 feet and then died or managed to get back to their hive and then died,” she said.

The Eugene die-off appears to be a repeat of an incident in a Wilsonville store parking lot this time last June, where about 50,000 bees were killed by chemical sprays.

Managers order the application of insecticides to linden trees to combat aphid infestations, Pokarney said.

“People park underneath the trees and aphids will fall on the car — or their (sticky waste) will fall on the car. It’s really kind of an unsightly thing,” he said.

Until last year, tree spray companies liked to use dinotefuran and imidacloprid, which are a class of insecticides called neonicotinoids.

When the companies sprayed the compounds on blooming linden trees, the result was bee death. Besides Wilsonville, it also happened at Hillsboro and Oregon City last year.

Neonicotinoids proved fatal on contact to bees, but they also may be killing additional bees more slowly.

A study out of Harvard this month suggested that bees surviving exposure to neonicotinoids may be more likely to freeze to death in the winter.

After the Wilsonville incident, the state banned the use of two neonicotinoids — dinotefuran and imidacloprid — on linden trees, and others trees in the Tilia family.

In February, the Eugene City Council banned their use on city property, winning the city the “America’s most bee-friendly city” honor.

The ban, however, doesn’t apply to private property, where home­owners or commercial applicators can use them.

The Eugene tree spray company most likely erred in its treatment of the Jacob Lane linden trees, Pokarney said.

“We know they used imidacloprid,” he said. “There are restrictions on its use, and using it under those conditions when pollinators are present is a violation.

“We have in the last year gone through extensive outreach and education of all of our licensed applicators — anybody who has a pesticide license with us — talking about this whole issue of using these two neonicotinoids on linden trees, period.

“There is every reason for us to believe that they should have been aware that they shouldn’t use this when there’s blooms, when there’s bees and on linden trees.

“As we pursue enforcement, we would look towards whether there was negligence involved, whether an application was done in a faulty or negligent manner.”

Fines the state levied in the wake of the Wilson­ville incident totaled $2,886.

During the Wilsonville incident, crews covered the trees with netting to prevent further bee exposure.

“We’re going to see if there are additional bee deaths, and if there are, what more can we do?” Pokarney said.

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