- This article is about the tree.This is Georgia's state tree. For places named Live Oak, see Live Oak.
Live oak or evergreen oak is a general term for a number of unrelated oaks in several different sections of the genus Quercus that happen to share the character of evergreen foliage.
The name live oak comes from the fact that evergreen oaks remain green and "live" throughout winter, when other oaks are dormant, leafless and "dead"-looking. The name is used mainly in North America, where evergreen oaks are widespread in warmer areas, along the Atlantic coast from Maryland to Florida, west along the Gulf Coast to Texas and across the southwest to California and southwest Oregon.
Evergreen oak species are also common in the warmer parts of Europe and Asia, and are included in this list for the sake of completeness. These species, although not having "live" in their common names in their countries of origin, are colloquially called live oaks when cultivated in North America.
When the term live oak is used in a specific rather than general sense, it most commonly refers to the Southern live oak (the first species so named), but can often refer to other species regionally.
The live oak is the official state tree of Georgia.
In Texas, a small grove of live oaks (Texas live oak or Southern live oak) is known as a mott.
Live oak was widely used in early American shipbuilding. Because of the trees' short height and low hanging branches, lumber from live oak was specifically used to make curved structural members of the hull such as knee braces. In such cuts of lumber the line of the grain would fall perpendicularly to lines of stress creating structures of exceptional strength. Live oak was not generally used for planking because the curved and often convoluted shape of the tree did not lend itself to be milled to planking of any length. Red oak or white oak was generally used for planking on vessels as those trees tended to grow straight and tall and thus would yield straight trunk sections of length suitable for milling in to plank lengths. Live oak was largely logged out in Europe by the latter half of the 19th Century and was similarly sought after and exported from the United States until iron and steel hulled commercial vesssel construction became the standard early in the 20th Century. Live oak lumber is rarely used for furniture due to warping and twisting while drying. It continues to be used occasionally when available in shipbuilding as well as for tool handles for its strength, energy absorption, and density, but modern composites are often substituted with good effect. Dry southern live oak
lumber has a specific gravity of 0.88, the highest of any North American hardwood.
Evergreen species in genus Quercus
- Section Quercus. The white oaks. Europe, Asia, north Africa, North America. Styles short; acorns mature in 6 months, sweet or slightly bitter, inside of acorn shell hairless.
- Section Cerris. Europe, Asia, north Africa. Styles long; acorns mature in 18 months, very bitter, inside of acorn shell hairless or slightly hairy.
- Section Protobalanus. Southwest USA, California coastal ranges & northwest Mexico. Styles short, acorns mature in 18 months, very bitter, inside of acorn shell woolly.
- Section Lobatae. The red oaks. North, Central & South America. Styles long, acorns mature in 18 months, very bitter, inside of acorn shell woolly.
See the list of Quercus species for a fuller listing of oaks including deciduous species.