Oregon white oak (Quercus garryana, also known as Garry oak) is a majestic, big-limbed tree native to the low elevations of the southern Pacific Northwest. Reaching up to 25 meters tall, the light gray bark is thick with ridges. Its leaves are alternately arranged, with rounded, deep lobes unique to an oak-type tree. They can get up to 12 centimeters long, are shiny and green on the top, with a lighter yellow-green underneath. The leaves are distinguishable from the poison oak plant by the number of leaflets and the margins of the leaves. The Oregon white oak is a monoecious tree with small male flowers in catkins, and female flowers in small clusters.
The huge limbs are a popular resting spot for fishnet lichen (ramalina menziesii), which have a symbiotic relationship with the tree. The gall wasp uses the limbs and leaves to lay its eggs, and the tree forms a defensive, protective layer around the eggs to shield them from the elements. It also produces edible acorns that helped sustain the native Kalapuya populations. The Oregon white oak is very susceptible to invasion by Douglas-fir and other conifers, and as such the Kalapuya would set fires to the Oak Savanna ecosystems, where the Oregon white oaks would stand tall and the conifers would be defeated. This perpetual setting of fires is very healthy for the oak savanna, and returns nutrients faster than regular decomposition methods.