quercus suber

Common Names: cork oak

Family: Fagaceae

Origin: Mediterranean

Type: Evergreen tree

Size: 30–60 ft. high and wide; prune to control.

Flowers: Tiny yellow-green flower, spring, acorns about 1.5 in. long; shiny dark green 3 in. leaves. Spectacular deeply furrowed and colorful bark.

Uses: Large areas, shade tree, focus, street tree, background, stunning bark. Tolerates heat. Fire resistive.

Wildlife: Acorns are food source. Butterfly larvae. Deer resistant.

Soil: Prefers well-drained soil. Tolerant of a variety of soils; foliage may turn yellow in highly alkaline soil.

Water: Low after established.

Sun: Full sun.

Pruning: May require formative pruning for prolonged tree health. Remove dead or damaged material in late autumn through winter.

Pests & Diseases: Aphids, powdery mildew, honey fungus.

Notes: After 25 years, about 1/3 of the tree’s cork is harvested every 9 to 15 years, primarily in Portugal, Spain, and Algeria. Look for many other oaks in various sizes in the Garden. Hardy to 10° F.