Quercus douglasii Fagaceae
Blue Oak, California Blue Oak KWER-kus dug-LAS-e-i
- Deciduous tree, typically 20-60(90) ft [6-18(27) m] tall, rounded top, short stout branches, ascending or horizontal, in the open the trunk may be short and foliage may reach the ground; shrubby in southwestern part of its range. Bark light gray and checkered into small squares. Leaves alternate, simple, 4-10 cm long with 5-7 irregular lobes, lobe sinuses are usually shallow, some leaves may be entire, dull bluish-green above and pale bluish-green below; fall colors are light pink, orange and yellow. Fruit (acorn), the nut is brown when ripe, egg-shaped, about 2-3 cm long, sharply pointed tip, acorn cups are saucer-shaped, 12-15 mm wide.
- Sun. Drought resistant, best in sandy soil, tolerates coastal winds.
- Hardy to USDA Zone 8? Native to the dry woodlands and valleys around the California's Central Valley and the interior valleys of southern California.
- Portland, Oregon: Hoyt Arboretum