Warning: Emerald Ash Borer (EAB), What You Need to Know
The Emerald Ash Borer is an invasive beetle threatening Oregon’s only native ash species, the Oregon Ash. After spreading across the eastern U.S., EAB has now arrived in the Pacific Northwest and is expected to cause widespread tree loss. The beetle’s larvae damage trees from the inside, cutting off water and nutrients. A key sign of infestation is the D shaped exit hole left on the bark when adults emerge.
Because Oregon Ash plays a major role in wetlands and streamside forests, losing it would affect water quality, habitat, and shade across much of northwest Oregon. Early awareness is essential.
What Residents Can Do
- Learn the signs of EAB. Look for thinning leaves, bark splitting, woodpecker foraging, and D shaped exit holes.
- Report suspected EAB immediately. Use the Oregon Invasive Species Hotline at OregonInvasivesHotline.org.
- Don’t move firewood. Moving wood spreads pests—buy it where you burn it.
- Protect healthy ash on your property. If you have Oregon Ash, consult with a certified arborist about monitoring and possible treatment options.
- Plant diverse species. When replacing trees, choose a variety of non ash natives to support long term forest and neighborhood resilience.
This native plant has been brought to you by the City of Beaverton’s Landscape & Urban Forestry Dept.
