Live Oak (Quercus virginiana) is also known as the southern live oak and the Virginia live oak. This tree is native to the southeastern United States.

Because Quercus virginiana retains its old leaves until new leaves develop, its common name "live oak" is used because it is considered to be an evergreen oak.

The bark of a live oak is thick and darker in color than that of a laurel oak. As shown in these photographs, live oak bark has deep, narrow, longitudinal furrows that become blocky as the tree ages.

A live oak has a deep tap root, as well as an extensive root system that spreads just below the surface. The tree can live in very poor soil and grow to a height of 50 feet with a 100-foot wide crown. Trees can live more than 300 years.

Live oak leaves are simple, alternate, and fold downward at the margins. They are elliptical to oval in shape, .75 to 6 inches long and .4 to 2 inches wide. Sometimes their edges have prickly-teeth. As shown in the two photographs below, the upper side of the leaf is stiff and leathery, dark green and glossy. The bottom of the leaf has soft short hairs and is grayish green.

Acorn production varies from year to year. Some years there are many, while other years there are very few or none. Acorns are .4 to 1 inch long and oblong in shape. They can be shiny and tan-brown to nearly black. The cap covers about 1/3 of the nut. Acorns are usually born in clusters of two to five.

 

Live oaks provide many uses for many organisms:

1) The trunk and limbs provide a place for attachment for air plants (ball moss, Spanish moss, resurrection fern, mistletoe).

2) Acorns and leaves are an important food source for birds, mammals (bears, squirrels, and deer), and caterpillars (hairstreak butterfly and oakworm moth).

3) Foliage provides nesting sites, shelter, and shade for a variety of species.

4) Native Americans extracted a cooking oil from acorns. They used all parts of the live oak for medicinal purposes, and leaves for rug making and bark for dyes.

5) Because live oak is hard, heavy, and strong, in the days of wooden ship building, live oak was the preferred wood to use for framework timbers. The United States Navy used live oak to construct the USS Constitution prior to its first launch in 1797. The density of the wood grain allowed it to survive cannon fire from a British frigate in the War of 1812. As a result, the ship was nicknamed "Old Ironsides". The USS Constitution was used by the United States Navy from 1797 until 1855. Today, it is considered the world's oldest commissioned warship afloat and serves as a floating museum that is tugged into Boston Harbor several times each year. In 2012, it sailed on its own with 285 people aboard to celebrate the 200th anniversary of the 1812 battle.

6) Today, live oak is cultivated as a shade and ornamental tree.