Willamette Valley - Ecology

Ecology

The Willamette Valley is prone to periodic floods. Notable floods include the Great Flood of 1862, events in 1899, Pacific Northwest flood of 1964, and the Willamette Valley Flood of 1996. Part of its floodplain is a National Natural Landmark called the Willamette Floodplain.

North Pacific Oak Woodland is a major forest alliance, extending through the Willamette Valley and southward to the Klamath Range of Northern California. Many of the soils are well-drained mesic.