Columbia Plateau

The Columbia Plateau Ecoregion encompasses part of Oregon and most of eastern Washington. The Oregon portion of the ecoregion extends from the eastern slopes of the Cascades Mountains, south and east from the Columbia River to the Blue Mountains.

Millions of years ago, the region was covered by lava flows up to two miles deep. The centerpiece of the ecoregion, the Columbia River, has greatly influenced the surrounding area, with cataclysmic floods and large deposits of wind-borne silt and sand. Over time, winds scoured the floodplain, depositing silt and sand across the landscape and creating ideal conditions for agriculture: rolling lands, deep soil, and plentiful flowing rivers including the lower parts of the Deschutes and John Day Rivers. The ecoregion is made up entirely of lowlands, with an arid climate, cool winters and hot summers.

The Columbia Plateau produces the vast majority of Oregon’s grain, and grain production is the heart of the agricultural economy. The Columbia Plateau produces the second-highest agricultural sales per year for any ecoregion in Oregon. More than 80 percent of the ecoregion’s population and employment is located in the Umatilla County portion of the ecoregion, which includes Pendleton and Hermiston. Other population centers include The Dalles, Condon, and Heppner.

text taken from the Oregon Conservation Strategy, 2006, Oregon Department of Fish and Wildlife

Update

The Oregon Master Naturalist Program is currently developing a statewide curriculum. In time, the Columbia Plateau ecoregion will have a specific regional supplement that will give participants a more in depth look at the region. Continue to check this web site for an update as regionally specific supplements are added.