Washington Title Image Large
© Pete Saloutos/Panoramic Images (Washington Title Image Large)

Blue Mountains Ecoregion

Washington’s smallest ecoregion, the rugged Blue Mountains are a rolling high plateau dotted with ponderosa pine forests, vestiges of Palouse prairie, and steeply cut rimrock canyons.


The Blue Mountains spill over into Washington’s extreme southeastern corner. Just 1% of Washington lies within the Blue Mountains.

They are the westernmost ranges of the Middle Rockies that extend south into Oregon and east across central Idaho and into Montana.

Highway 129 is the only road through Washington’s portion of the ecoregion. It heads south along the Snake River from Clarkston through Asotin and Anatone. Then it climbs over Rattlesnake Pass before descending the precipitous switchbacks to the Grande Ronde River and continuing to Enterprise, Oregon.

For details of this ecoregion within Washington, click a subheading in the left column.

View the more general description of this ecoregion in North America

From Our Content Partner

Go to the Map

Use the interactive map to zoom smoothly from a national view to state and local perspectives anywhere across the country.

Copyright © 2023 NatureServe. All Rights Reserved.