More trees appear to be dead or dying along Highways 20 and 126 near Sisters, just a few years after a massive die-off tied to a now-restricted herbicide.
The U.S. Forest Service in 2019 cut about 2,100 trees — most of them ponderosa pines — along Highway 20 in Jefferson County after they were accidentally poisoned and killed by the herbicide Perspective.
A contractor for the Oregon Department of Transportation had sprayed weeds near the highway to mitigate wildfire risk. That herbicide found its way to the tree roots, causing them to slowly die.
The Oregon Department of Agriculture effectively banned Perspective shortly after the die-off, and the state transportation agency no longer uses it.
An ODOT spokesperson says these new tree deaths could be from the herbicide lingering in the environment, drought or some other combination of factors.
“It’s a pretty stressful time to be a tree,” said Kacey Davey, a public information officer for ODOT. “There’s no definite way of telling, but it is a possibility that [Perspective] could be what caused those trees to go.”
The Sisters Nugget newspaper first reported the new tree deaths.
The agency will survey the corridor this fall for hazard trees. Any trees deemed a hazard within the ODOT right of way will be removed, Davey said. ODOT will also work with landowners to assess and/or remove hazard trees on private property.