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.

They range in size from 30 to 90 centimetres (1 to 3 ft) in length and contain 10–41 leaflets organised in pairs, with the largest leaves found on vigorous young sprouts.

[17][15] The male flowers are similar in appearance, but they lack a pistil and the stamens do function, each being topped with a globular anther and a glandular green disc.

[20] The females can produce huge numbers of seeds, normally around 30,000 per kg,[10] and fecundity can be estimated nondestructively through measurements of diameter at chest height.

The tree has been grown extensively both in China and abroad as a host plant for the ailanthus silkmoth, a moth involved in silk production.

[21][22] The first Western scientific descriptions of the tree of heaven were made shortly after it was introduced to Europe by French Jesuit Pierre Nicholas d'Incarville, who had sent seeds from Peking via Siberia to his botanist friend Bernard de Jussieu in the 1740s.

In London, the specimens were named by Miller as Toxicodendron altissima, and in Busbridge, it was dubbed in the old classification system as Rhus Sinese foliis alatis.

[24] Light was shed on the taxonomic status of Ailanthus in 1788 when René Louiche Desfontaines observed the samaras of the Paris specimens, which were still labelled Rhus succedanea, and came to the conclusion that the plant was not a sumac.

He published an article with an illustrated description and gave it the name Ailanthus glandulosa, placing it in the same genus as the tropical species then known as A. integrifolia (white siris, A.

[48] In Montenegro[54] and Albania[55][56] A. altissima is widespread in both rural and urban areas, and while in the first it was introduced as an ornamental plant, it very soon invaded native ecosystems with disastrous results and became an invasive species.

For example, a 2003 study in North Carolina found the tree of heaven was present on 1.7% of all highway and railroad edges in the state, and had been expanding its range at the rate of 4.76% counties per year.

[62] Similarly, another study conducted in southwestern Virginia determined that the tree of heaven is thriving along roughly 30% of the state's interstate highway system length or mileage.

[10] On the other hand, a study in an old-growth hemlock–hardwood forest in New York found that Ailanthus was capable of competing successfully with native trees in canopy gaps where only 2-15% of full sun was available.

[47] Ailanthus has been used to re-vegetate areas where acid mine drainage has occurred and it has been shown to tolerate pH levels as low as 4.1 (approximately that of tomato juice).

[73] Along highways, it often forms dense thickets in which few other tree species are present, largely due to the toxins it produces to prevent competition.

One study showed that a crude extract of the root bark inhibited 50% of a sample of garden cress (Lepidium sativum) seeds from germinating.

The same study tested the extract as an herbicide on garden cress, redroot pigweed (Amaranthus retroflexus), velvetleaf (Abutilon theophrasti), yellow bristlegrass (Setaria pumila), barnyard grass (Echinochloa crusgalli), pea (Pisum sativum cv.

[76] Another experiment showed that a water extract of the chemical was either lethal or highly damaging to 11 North American hardwoods and 34 conifers, with the white ash (Fraxinus americana) being the only plant not adversely affected.

[48] Several species of Lepidoptera use the leaves of Ailanthus as food, including the Indian moon moth (Actias selene) and the common grass yellow (Eurema hecabe).

It involves the application of foliar or basal herbicides to kill existing trees, while either hand pulling or mowing seedlings to prevent new growth.

The problem of odor was previously avoided by only selling pistillate plants since only males produce the smell, but a higher seed production also results.

In the United Kingdom it is especially common in London squares, streets, and parks, though it is also frequently found in gardens of southern England and East Anglia.

[87] A few cultivars exist, but they are not often sold outside of China and probably not at all in North America:[citation needed] Nearly every part of A. altissima has had various uses in Chinese traditional medicine,[96] although there is no high-quality clinical evidence that it has an effect on any disease.

This derives from the literature of Zhuangzi, a Taoist philosopher, who referred to a tree that had developed from a sprout at the stump and was thus unsuitable for carpentry due to its irregular shape.

The tree is associated with the black prisoner's despair in the face of his impending execution and the spirituals that he sings in chorus with other black people who keep a sort of vigil in the street below: ...they sang spirituals while white people slowed and stopped in the leafed darkness that was almost summer, to listen to those who were sure to die and him who was already dead singing about heaven and being tired; or perhaps in the interval between songs a rich, sourceless voice coming out of the high darkness where the ragged shadow of the heaven-tree which snooded the street lamp at the corner fretted and mourned: "Fo days mo!

"[100] Upon the barred and slitted wall the splotched shadow of the heaven-tree shuddered and pulsed monstrously in scarce any wind; rich and sad, the singing fell behind.

It would be considered beautiful except that there are too many of it.In the 2013 book Teardown: Memoir of a Vanishing City by Gordon Young, the tree is referenced in a description of the Carriage Town neighborhood in Flint, Michigan.

Festive Victorian-era homes in various stages of restoration battled for supremacy with boarded-up firetraps and overgrown lots landscaped with weeds, garbage, and "ghetto palms," a particularly hardy invasive species known more formally as Ailanthus altissima, or the tree of heaven, perhaps because only God can kill the things.

[104]Until 26 March 2008, a 60-foot-tall (18 m) member of the species was a prominent "centerpiece" of the sculpture garden at the Noguchi Museum in the Astoria section in the borough of Queens in New York City.

The museum hired the Detroit Tree of Heaven Woodshop, an artists' collective, to use the wood to create benches, sculptures and other amenities in and around the building.