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California Blue Oak, Iron Oak
Scientific Name: Quercus douglasii Hook. & Arn.
Family: Fagaceae

Show Larger Picture Picture U.S.D.A Forest Service, Courtesy of the Hunt Institute

Recommended Temperature Zone: sunset: 1-11,14-24 USDA: 5-10 Sun Exposure: Full sun Origin: California (USA), around the Central Valley Growth Habits: Deciduous tree, growing rather slowly to 20 to 65 feet tall (6-20 m), 20 to 50 feet spread (6-15 m); trunk 14 to 24 inches in diameter (35-60 cm); thin and flaky bark; leathery, wavy blue green leaves, with a yellowish-green underside, 1 to 3 inches long (2.5-7.5 cm). Watering Needs: Little water and good drainage, flood tolerant Propagation: Fresh seeds (acorns) best sown in place since the seedling rapidly develops a large taproot

Fruiting Habits:
The edible acorns are 0.8 to 1.2 inches long (2-3 cm), with a shallow cup, usually solitary, maturing in a single season, and germinating without a rest period.