Willamette Valley, Oregon, USA Photograph by Maureen Raad   Western North America: Western United States Temperate Broadleaf and Mixed Forests   5,800 square miles (14,900 square kilometers) -- about the size of Connecticuit and Rhode Island combined Critical/Endangered

· Fertile Valley
· Special Features
· Did You Know?
· Wild Side
· Cause for Concern
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Fertile Valley

Surrounded by snow-capped volcanic peaks and wet temperate forests, this valley once supported a mixture of Douglas fir forests, oak woodlands, prairies, and wetlands.

Special Features

Throughout history, fire shaped the biodiversity of the Willamette Valley. Periodic burning by Native Americans created ideal conditions for native perennial grasses. In fact, the entire ecoregion was once a prairie supporting oak stands and groves of Douglas fir and other trees. When agriculture and development spread through the region and people started suppressing wild fires, forests gradually began to replace most of the savanna in the valley. The landscape today, therefore, looks much different from what it did in its original state.

	The mountain beaver is neither a beaver nor particularly associated with mountains. A mountain beaver is actually the lone member of its family and is thought to be the most primitive rodent.

Wild Side

The Willamette Valley is the only home in the world for a yellow-flowered member of the parsley family called Bradshaw's lomatium. It is also the sole wintering area of the dusky Canada goose and is home to the Camas pocket gopher, the largest gopher in the Pacific Northwest. The mixture of Douglas fir and white oak forests with local areas of western hemlock and western red cedar provide habitat for blacktail deer, elk, red foxes, opossums, beavers, striped skunks and mountain beavers. In the valley's grasslands, there is a mixture of danthonia, bentgrass, orchard grass, needle grass, fescue, and prairie June grass. During the summer, the skies are filled with red-tailed hawks, Cooper's hawks, sharp-shinned hawks, and kestrels. And in the winter, the major valley bottoms serve as habitat for rough-legged, red-tailed, and Swainson's hawks. Around wetlands and along bodies of water, you can find a mixture of trees such as cottonwood, willow, ash, and alder. Throughout the region, many lakes, reservoirs, and streams support populations of rainbow trout, shad, and smelt. Feasting on the abundant fish are birds such as great blue herons and ospreys.

Cause for Concern

Cultivation and development have destroyed nearly all of the natural habitat in the Willamette Valley. Just one-tenth of one percent of the valley's native grasslands and oak savannas remains today. This tiny fragment of the original ecosystem is itself split into fragmented patches, the largest of which are no greater than 14 square miles (35 square kilometers). Most of the prairie and riparian areas are gone completely, and much of the original savanna has been converted to forest because of fire suppression. The Willamette Valley contains approximately 70 percent of the state's human population.

For more information on this ecoregion, go to the World Wildlife Fund Scientific Report.