Ailanthus (Tree-of-Heaven)

Ailanthus altissima commonly known as tree of heaven, ailanthus, or in Standard Chinese as chouchun (Chinese: 臭椿; pinyin: ch�uchÅ«n; literally “malodorous tree”), is a deciduous tree in the Simaroubaceae family. It is native to both northeast and central China and Taiwan. Unlike other members of the genus Ailanthus, it is found in temperate climates rather than the tropics. The tree grows rapidly and is capable of reaching heights of 50 ft in 25 years. However, the species is also short lived and rarely lives more than 50 years. The tree was first brought from China to the United States in 1784. A. altissima is a medium-sized tree that reaches heights between 56 and 90 ft with a max diameter at breast height of about 40 in.

The LEAVES are large, odd or even-pinnately compound, and arranged alternately on the stem. They range in size from 1 to 3 ft in length and contain 10�41 leaflets organized in pairs, with the largest leaves found on vigorous young sprouts. The rachis is light to reddish-green with a swollen base. The leaflets are ovate-lanceolate with entire margins, somewhat asymmetric and occasionally not directly opposite to each others. Each leaflet is 2.0 to 7.1 in long and 0.98 to 2.0 in wide. They have a long tapering end while the bases have two to four teeth, each containing one or more glands at the tip. The leaflets’ upper sides are dark green in color with light green veins, while the undersides are a more whitish green. The petioles are 0.20 to 0.47 in long. The lobed bases and glands distinguish it from similar sumac species.

The BARK is smooth and light grey, often becoming somewhat rougher with light tan fissures as the tree ages. The TWIGS are stout, smooth to lightly pubescent, and reddish or chestnut in color. They have lenticels as well as heart-shaped leaf scars (i.e. a scar left on the twig after a leaf falls) with many bundle scars (i.e. small marks where the veins of the leaf once connected to the tree) around the edges. The BUDS are finely pubescent, dome shaped, and partially hidden behind the petiole, though they are completely visible in the dormant season at the sinuses of the leaf scars.

In China, the tree of heaven has a long and rich history. It was mentioned in the oldest extant Chinese dictionary and listed in countless Chinese medical texts for its purported ability to cure ailments ranging from mental illness to baldness. The roots, leaves and bark are still used today in traditional Chinese medicine, primarily as an astringent.