First Wilsonville, now Hillsboro - bees are dying by the thousands, and an insecticide may be to blame.
Last week, 50,000 bees died in a Wilsonville Target parking lot.
Now it appears the same thing could be happening in Washington County.
The Xerces Society found that an insecticide known as Safari was used on the tree in Wilsonville that caused what turned out to be the largest mass bumblebee death on record.
The cause of the dead bees in Hillsboro has not been determined, but city officials said Safari was used in trees there as well.
People started noticing the dead bees this past weekend.
There was a concentration of hundreds of them around a tree on SW Washington Street between 4th and 5th avenues.
The city contacted the Oregon Department of Agriculture and The Xerces Society, who have taken samples and are testing them this week.
The city sprayed Safari on the tree back in March, as well as other trees in the area.
The insecticide is meant to kill aphids but ended up killing 50,000 bees in Wilsonville last week.
The deaths are considered catastrophic because they represented more than 300 colonies that would've produced multiple new queens who would've gone on to establish new colonies next year.
Hillsboro city employees have put a net around the tree where the dead bees were found.
They say even though it has not been confirmed that the pesticide is to blame, they still want to prevent as many bees from getting to it as possible.
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