tree of heaven - Ecology, Cultivation and uses

A fast-growing deciduous tree (Ailanthus altissima) to 20–30 m/65–100 ft, native to China, and widely planted elsewhere for ornament, shade, and as a soil stabilizer; leaves pinnate, with 13–25, 2–4-toothed leaflets, red when young; flowers in large clusters, starry, greenish-white, strong-smelling; fruit with an elongated wing. (Family: Simaroubaceae.)

iAilanthus altissima
Leaves and flowers
Scientific classification
Kingdom: Plantae Division: Magnoliophyta Class: Magnoliopsida Order: Sapindales Family: Simaroubaceae Genus: Ailanthus Species: A. altissima
Binomial name
Ailanthus altissima (Mill.) Swingle

Ailanthus altissima (Tree of Heaven or Ailanthus) is a member of the quassia family, Simaroubaceae, native to northeast and central China. It is a deciduous tree, which grows rapidly and can reach up to 25 m tall, rarely 35 m, with a trunk up to 1 m diameter, rarely 1.5 m diameter. Other common names include china sumac, copal tree, stinktree and ghetto palm.

The bark of the tree is smooth and light grey, while the stems are reddish or chestnut.

The flowers are small, yellow-green to reddish, produced in late spring to mid summer in panicles up to 30 cm long. All parts of the tree produce an unpleasant odour, suggestive of rancid cashews, with male flowers having the strongest smell.

In overall appearance, it is somewhat similar to some species of sumac;

There are two varieties:

Ailanthus altissima var.

Ecology

Ailanthus is an opportunistic species, thriving in full sun and in disturbed areas. Ailanthus is among the most tolerant of all tree species to pollution, including sulfur dioxide, and high soil acidity such as that from acid mine drainage (as low as pH 4.1). Along highways it often forms dense thickets in which few other tree species are present.

Ailanthus produces allelopathic chemicals, which inhibit the growth of other plants.

People have suggested many factors to Ailanthus' success at naturalising, including the absence of insects eating the plant, lack of exposure of native plants to the Ailanthus' allelopathy, and the widespread human disturbances which favour the tree.

Cultivation and uses

Tree of Heaven is a popular ornamental tree in China, valued for its tolerance of difficult growing conditions, and its uses in Chinese traditional medicine.

There are records of the wood from this tree being used in China. There are problems with using the wood, because the trees exhibit extremely rapid growth for the first few years, the trunk has uneven texture between the inner wood and outer wood, which can cause the wood to twist and/or crack when it is dried after it is cut. Although the live tree tends to have very flexible wood, the wood is quite hard once properly dried.

It was first introduced to Europe (France and England) by a French Jesuit priest returning from Nanking in 1751, and the United States by William Hamilton, a gardener in Philadelphia in 1784.

Synonyms of A.

Control

Tree of Heaven has become a problematic invasive species in many areas with warm temperate climates, including Africa, the Americas, Australia, Europe, and New Zealand.

Because of its aggressive spread, vigorous growth, allergenic and allelopathic chemicals, it has become a problem in many areas, out-competing native species.

Cutting alone is not sufficient to kill the tree, as it resprouts quickly and abundantly, so eradication programs generally resort to herbicides. Literature

The book A Tree Grows in Brooklyn by Betty Smith referred to the Tree of Heaven, using it as an analogy for the ability to thrive in a difficult environment.

The Chinese name for this tree contains the descriptive word "stinky".

In some parts of China, unwanted or worthless children may be contemptuously called "ailanthus shoots" .