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Oak

By any standard, the oak is a mighty tree. It is significant in sheer numbers alone, with oak trees being the most widespread hardwoods in the temperate zone of the northern hemisphere. The oak is also impressive in stature, with species ranging in mature height from 35 to more than 100 feet and the world champion red oak living up to the Quercus’ popular title as King of Trees by reaching 134 feet.

Despite their great variety, oaks share several distinctive characteristics. They all grow from acorns and can live for centuries. Most species also share a common shape, being rounded with a broadly spreading crown. They are also damage-resistant, hardy trees that have merited admiration and respect for the shelter and many vital products their wood has long provided Americans.

The Oak's Place in History

Its amazing strength, beauty, and longevity have made the oak a central part of much of American history. Abraham Lincoln found his way across a river near Homer, Illinois, using the Salt River Ford Oak as a marker. The Richards White Oak in Cecil County, Maryland once served as a landmark on a 1681 map used by William Penn. Andrew Jackson took shelter under Louisiana’s Sunnybrook Oaks on his way to the Battle of New Orleans. And “Old Ironsides,” the USS Constitution, earned its nickname from the strength of its live oak hull, famous for easily repelling British cannonballs.

Some Common Species

Oak species are sometimes divided into one of two major groups, the red oaks (Erythrobalanus) and white oaks (Leucobalanus). More information is provided below on three species, the white oak (Quercus alba) the northern red oak (Quercus rubra), and the live oak (Quercus virginiana).The white oak can live for centuries, making it both rich in history and the dominant tree in many landscapes. The national champion of this species, Maryland’s Wye Oak, stands 79 feet tall with a spread of more than 100 feet. Their natural range extends from Minnesota to Maine in the north and from Georgia to Texas in the south, although they can be found in an even wider area. The wood of the white oak holds liquids well and so is often used in barrel making. (Grows in hardiness zones 3 to 9.)

The northern red oak has been called “one of the handsomest, cleanest, and stateliest trees in North America” by naturalist Joseph S. Illick, and it is widely considered a national treasure. It is especially valued for its adaptability and usefulness, including its hardiness in urban settings. This medium to large tree is known for its brilliant fall color and great value to wildlife. (Grows in hardiness zones 3 to 8.)

The live oak is a memorable symbol of the American South. With its massive trunk and vastly spreading limbs, this long-lived oak is at home in the coastal Southeast and is almost always pictured draped in Spanish moss. The strong, dense wood of this magnificent tree once made it the choice for many a ship’s hull, though today the live oak finds a cherished place as a Southern street and shade tree. (Grows in hardiness zones 8 to 10.)

There are nearly 60 oaks native to the United States, with some native to very small ranges that illustrate just how diverse the genus Quercus truly is. Within California, for example, many oak species with very limited natural ranges exist, including blue oak and valley oak, making possible such specific goals as restoring native oak savannah ecosystems. And in the East, the Stone Mountain oak grows only on the rock surface of Stone Mountain, near Atlanta, Georgia, and in a few similar areas, while a species like the Oglethorpe oak is rare enough to be found only in isolated areas of South Carolina and Georgia.