With its variety of climatic conditions and surface features, Oregon has a diverse assortment of vegetation and wildlife, including 78 native tree species. The coastal region is covered by a rain forest of spruce, hemlock, and cedar rising above dense underbrush. A short distance inland, the stands of Douglas fir—Oregon's state tree and dominant timber resource—begin, extending across the western slopes to the summit of the Cascade Range. Where the Douglas fir has been destroyed by fire or logging, alder and various types of berries grow. In the high elevations of the Cascades, Douglas fir gives way to pines and true firs. Ponderosa pine predominates on the eastern slopes, while in areas too dry for pine the forests give way to open range, which, in its natural state, is characterized by sagebrush, occasional juniper trees, and sparse grasses. The state's many species of smaller indigenous plants include Oregon grape—the state flower—as well as salmonberry, huckleberry, blackberry, and many other berries. Eighteen Oregon plant species were listed as threatened or endangered in 2003 (up from eight in 1997), including the Willamette daisy, Western lily, Malheur wire-lettuce, rough popcornflower, and MacFarlane's four-o'clock.
More than 130 species of mammal are native to Oregon, of which 28 are found throughout the state. Many species, such as the cougar and bear, are protected, either entirely or through hunting restrictions. The bighorn sheep, once extirpated—deliberately exterminated—in Oregon, has been reintroduced in limited numbers; the Columbian white-tailed deer, with an extremely limited habitat along the Columbia River, is still classified as endangered. Deer and elk are popular game mammals, with herds managed by the state: mule deer predominate in eastern Oregon, black-tailed deer in the west. Among introduced mammals, the nutria and opossum are now present in large numbers. At least 60 species of fish are found in Oregon, including five different salmon species, of which the Chinook is the largest and the coho most common. Salmon form the basis of Oregon's sport and commercial fishing, although dams and development have blocked many spawning areas, causing a decline in numbers and heavy reliance on hatcheries to continue the runs. Hundreds of species of birds inhabit Oregon, either year-round or during particular seasons. The state lies in the path of the Pacific Flyway, a major route for migratory waterfowl, and large numbers of geese and ducks may be found in western Oregon and marshy areas east of the Cascades. Extensive bird refuges have been established in various parts of the state. Thirty-six Oregon animal species were classified as threatened or endangered in 2003 (up from 21 in 1997), including the short-tailed albatross, bald eagle, Fender's blue butterfly, three species of chub, brown pelican, northern spotted owl, and three species of sea turtle.