Hundreds of ‘danger trees’ to be felled along Hwy. 20 near Sisters

(Update: Adding estimate that several hundred trees to be removed)

The Sisters Ranger District said Wednesday it is seeking public comment on a project to remove several hundred dead or dying “danger trees” along more than 12 miles of U.S. Highway 20 near Sisters, the result of roadside herbicide spraying that went awry.

The plan is to remove trees that pose a hazard to public safety because of their potential to fall across the highway, the Deschutes National Forest announcement said. Only the dead and dying trees would be removed.

The roadside project area includes 11.5 miles of Highway 20 beginning in Sisters and extending to the northwest, as well as a 1-mile section southeast of Sisters.

The trees would be felled and removed are mostly right next to the highway, though some in a second zone within “striking distance” of the road also would be taken out. Ultimately, the trees removed from a roughly 436-acre area would be utilized for forest products, officials said.

The project is needed because from 2013 to 2015, an herbicide was used along the highway corridor, within the Oregon Department of Transportation’s right of way, to remove brush. The herbicide harmed Ponderosa pines and other trees in the area where it was applied.

In 2014, foresters began noticing the occurrence of stressed trees along Highway 20, many of which later died. Since that time, foresters have connected that tree stress and associated mortality to the herbicide use.

ODOT and the Forest Service jointly investigated and learned the maker of the herbicide, called Perspective, that ODOT applied along the road shoulders to control weeds and brush contains an active ingredient known to harm Ponderosa pine and other trees. The agencies said at the time the label did not say specifically it would damage Ponderosa pines.

ODOT has since discontinued use of the herbicide in areas with trees, and the Forest Service also discontinued its use in Oregon and Washington.

During the felling of the trees, which might occur as early as this fall, flaggers would be used as necessary to maintain safety along the highway and travelers might experience some delays, expected to be up to 20 minutes. The work is expected to take place during the spring or fall “shoulder seasons,” and conducted as quickly as possible, to limit impacts to highway traffic.

Logging gear would pull the felled trees away from the highway, to temporary landing locations. The highway shoulder would be kept free of logging debris or other obstructions, while other removed fuels would be piled and burned or chipped after the trees are felled. Slash cleanup would take place within a year, to meet “visual quality standards,” the agency said.

People interested in learning more about the Highway 20 Corridor Public Safety Project should contact Michael Keown, Sisters Ranger District environmental planner at 541-549-7735. Comments will be taken for 30 days and can be made through mail, in person or by e-mail at comments-pacificnorthwest-deschutes-sisters@fs.fed.us .