Oxydendrum is more commonly known as the sourwood tree because of the sour taste of its leaves. Also called the sorrel tree and the lily of the valley tree, Oxydendrum grows as a native tree throughout much of the southeastern United States. The tree grows to about 30 feet (9 meters) in height, but can reach heights as great as 60 feet (18 meters). At maturity, it has a spread of about 20 feet (6 meters).
The branches of the sourwood tree are a favorite meal for deer. The reddish-brown Oxydendrum wood is most often used for firewood and for pulp. It is also known as a honey tree, with bees attracted by its copious flowers.
Oxydendrum is valued for its healing properties in traditional medicine. A tea of the tree’s leaves is often made to aid in hydration and cooling. In traditional medicine, various parts of the tree were used for treating fevers, soothing pain, and treating digestive ailments.
Oxydendrum is popular with homeowners and gardeners for the large, fragrant clusters of white flowers it produces in mid-summer. The panicles of flowers are often 10 inches (25 cm) long. Oxydendrum is also selected for landscaping because of its brilliant orange and red fall colors. It is among the first trees to begin displaying foliage in late summer or early fall.
The only species in its genus, Oxydendrum is in the scientific family Ericaceae. Considered both an ornamental tree and a shade tree, it has dark green leaves and drooping branches. It often grows in an oval shape. It is considered to grow at a slow to medium pace and does not do well in areas with heavy air pollution.
The sourwood tree should be planted in full sun and in well-draining soil in the spring of the year. The tree has some degree of drought tolerance. It is a remarkably healthy tree and is rarely impacted by disease or pests.
Sometimes used as a patio tree, the Oxydendrum produces clusters of fruit that contain the seed. The fruits are less than 0.5 inch (1.2 cm) in size and brown. The fruit clings to the tree until mid-winter, when it finally falls to the ground.
In addition to the sourwood tree found growing wild, two hybrid varieties have been developed. Mt. Charm is known for brighter foliage than the wild tree. Chameleon is known for having a rainbow of fall colors in comparison to the wild tree.