Quercus lobata

Quercus lobata, commonly called the valley oak or roble, grows into the largest of California oaks. It is endemic to California, growing in interior valleys and foothills from Siskiyou County to San Diego County. Mature specimens may attain an age of up to 600 years. This deciduous oak requires year-round access to groundwater. Its thick, ridged bark is characteristic and resembles alligator hide. The valley oak's deeply lobed leaves assist in identification. Description The valley oak may surpass in height, with a sturdy trunk possibly exceeding in diameter. The "Henley Oak", in Covelo, California, is the tallest known valley oak, at . The branches have an irregular, spreading and arching appearance. During autumn, the leaves turn a yellow to light orange color but become brown later in the season. In advancing age, the branches droop. The trees have pewter-colored rippled bark.