Appearance

Tree-of-heaven has smooth, gray bark with chestnut brown twigs. It's leaves are large, growing to be one to four feet in length, and contain between 11 and 25 smaller leaflets. In June, it produces large clusters of small yellowish-green flowers, some of which have an unpleasant odor. Come summer, the female trees produce flat, twisted, single-seeded winged fruits.

Reproduction and Life Cycle

Tree-of-heaven grows quickly and is a prolific seeder. It's estimated that one tree can produce 325,000 seeds in a year. Tree-of-heaven also contains chemicals that act as a herbicide, affecting the growth of plants around it. It establishes dense stands and blocks native plants. The tree reproduces through seeds and vigorous resprouting, particularly in response to injury.

Did You Know?

• Tree-of-heaven is also known as stinking sumac and ailanthus.
• Before removing tree-of-heaven, be sure you are not mistaking it for staghorn sumac, ash or walnut.
• Tree-of-heaven was first introduced in the United States in 1784, and by the 1840s was commercially available.

Sources and Additional Information

• Ailanthus altissima - U.S. Forest Service
• Invasive Plant Manual - Southeast Exotic Pest Plant Control
• National Invasive Species Information Center - U.S. Department of Agriculture National Agricultural Library
• Tree of Heaven - National Park Service