Roadside vegetation



Maintenance of roadside vegetation (trees, brush, etc.) growing in the road right-of-way is the responsibility of the property owner or lawful occupant (ORS 368.256(b)). This includes vegetation hanging over the road, covering signs, blocking light from street lights or impairing visibility at intersections.

Washington County maintains some landscaped areas that were installed as part of a transportation improvement project. Landscaped or vegetated areas installed as part of a development are the responsibility of the homeowners of the development.

Where do I need to trim vegetation?

  • Around signs and under street lights
  • At corners and intersections
  • Near sidewalks and walkways
  • Over and next to the traveled roadway

Trees and shrubs must be trimmed to a minimum of:

  • 12 feet directly over portions of roadway
  • 2 feet in from the edge of the roadway
  • 9 feet directly over all portions of sidewalks and walkways


The County may trim trees or other vegetation within the road right-of-way when it's identified as an immediate hazard or as having adverse impacts to the road or traveling public.


Vegetation must be maintained in open roadside ditches to ensure stormwater filtration and to prevent erosion. Please do not use herbicide or eliminate vegetation in ditches.

Roadside shoulder spraying

Roadside shoulder spraying is a routine maintenance activity. It's performed every year to keep vegetation from encroaching into roadways. Property owners can submit a "No Spray" Program Agreement if they don't want vegetation adjacent to their property sprayed.However, vegetation must be maintained by the agreement holder to prevent vegetation from encroaching upon the roadway and to control a buildup of vegetated matter that prevents effective roadside drainage .

For more information call (503) 846-ROAD (846-7623) or email