Oregon White Oak
Quercus garryana · Deciduous Broadleaf Hardwood
Plant Family
Fagaceae
Tree Category
Shade Tree, Nut Tree, Forest Tree
Variety / Cultivar
None (Wild Species)
Hardiness Zones
USDA Zones 5-11; very adaptable to Mediterranean-style climates with wet winters and dry summers.
About This Tree
A massive, sturdy tree with a broad, rounded canopy and thick, gnarled branches. It features a deep taproot and a heavy-set trunk, growing slowly to reach impressive size and age over several centuries.
Leaf Characteristics
Simple, alternate, 3-6 inches long with deep, rounded lobes. Leathery texture, dark green above and paler underside; turns yellow-brown or reddish-brown in autumn.
Bark Characteristics
Light gray to whitish color, thick and corky with narrow furrowed ridges and scaly plates; provides excellent resistance to ground fires.
Growing Information
Origin Region
Pacific Northwest (Northern California to British Columbia)
Growing Season
Buds swell in mid-spring; flowers appear with new leaves in April/May; acorns ripen by September-October; leaves drop in late autumn.
Sunlight & Water Needs
Full Sun; low water needs once established; highly drought tolerant; prefers well-drained soil but can tolerate seasonal flooding.
Mature Size
40-90 feet tall with a 30-60 foot spread; slow growth rate; can live over 300-500 years.
Special Characteristics
Extreme drought tolerance; fire-resistant bark; produces high-quality hardwood timber; critical 'keystone' species for oak savanna ecosystems.
Wildlife & Ecology
Produces acorns consumed by squirrels, jays, and deer; supports over 200 species of caterpillars and insects; provides critical nesting sites for woodpeckers and owls.