Oak Woodlands

ECOSYSTEMS > INLAND OREGON > WOODLANDS

These woodlands are found primarily in western Oregon in areas of the Willamette Valley and limited parts of the Coast Range Mountains. They thrive at lower elevations and in drier conditions and may be mixed with prairie or savanna ecosystems as a result.

While Oregon white oak and California black oak trees may dominate in these ecosystems, they are frequently mixed with conifers including Douglas-fir and ponderosa pine.

Penetration of sunlight to the ground level means that the understory in these woodlands is open and highly productive, containing a wide variety of grasses, shrubs and wildflowers.

Oak woodlands were once more prevalent than they are today. Before their range was converted for urbanization or agricultural use, these woodlands covered as much as a million acres in the Coast Range Mountains and hundreds of thousands of acres in the Willamette Valley. The introduction of conifers and invasive plant species further reduced the woodland's range. It is now estimated that only 5% of the historic oak woodlands remain in Oregon. Oak woodland restoration is a growing conservation concern throughout Oregon with private and public entities working together to increase these important ecosystems.