Cork Oaks in America
The Cork Oak is favored by many U.S. horticulturists as a hearty, evergreen shade tree. Mature trees can reach 75' tall and form a broad canopy of toothed, shiny dark green leaves that are silver-gray beneath. Chocolate brown acorns are held loosely in caps and provide food for bird and small animals.
The Cork Oak can be planted in a variety of well-drained soils and has water requirements ranging from dry to moderate. It is particularly favored in coastal regions as it is impervious to salt spray. The most important planting limitation is exposure to frost. Cork Oaks are recommended to Hardiness Zones 8 -11 (USDA). These zones represent areas with minimum temperatures above 10°F. Some sources suggest that Cork Trees can also be planted in Zone 7 locations.
Cork trees are relatively common in the western United States, where they are available from numerous nurseries. Some of the more prominent examples are found at the UC Davis campus and on the grounds of Disneyland. During WWII concern over cork shortages led to grafting cork oak onto black oak rootstock. No significant commercial utilization has been recorded.
Some links to outlets for purchasing cork oak acorns and seedlings: