Scientific name: Ailanthus altissima (Mill.) Swingle
Family: Simaroubaceae
Common names: Tree of heaven, Chinese sumac, pencil tree
Description
The Tree of Heaven is a fast‑growing deciduous tree that can reach heights of 20–30 m (65–100 ft) with a trunk diameter of up to 1 m (3 ft). The bark is smooth and gray‑brown, becoming shaggy with age. Its compound leaves are pinnate, typically 30–70 cm (12–28 in) long, bearing 10–41 leaflets that are long, narrow, and toothed. In summer, the tree produces large panicles of small, yellow-green, fragrant flowers. The fruit is a samara containing a single winged seed, facilitating wind dispersal. The tree is noted for its ability to thrive in disturbed urban environments and for its tolerance of poor soils, air pollution, and drought.
Native and introduced range
Native range: Central and northern China, Taiwan, and parts of the Korean peninsula.
Introduced range: First introduced to Europe in the late 18th century and to North America in the early 19th century as an ornamental and street tree. It is now widespread throughout the United States, Canada, and many parts of Europe, where it is considered an invasive species in numerous regions.
Ecology and invasive behavior
The species reproduces both sexually (via seeds) and vegetatively (through root suckers). Its prolific seed production, rapid growth, and tolerance of varied conditions enable it to outcompete native vegetation, particularly in disturbed sites such as roadsides, abandoned lots, and forest edges. The tree’s allelopathic chemicals, notably ailanthone, can inhibit the germination and growth of neighboring plant species. Control methods include mechanical removal (cutting and root excavation), repeated mowing, and the application of systemic herbicides.
Economic and cultural uses
Historically, Ailanthus altissima was valued for its rapid shade provision and ability to stabilize soils. The wood is soft, lightweight, and has been used for low‑strength applications such as pulp, particle board, and cheap furniture. Extracts from the bark and leaves have been employed in traditional Chinese medicine for their purported anti‑inflammatory and antimicrobial properties, though scientific validation is limited.
In literature, the tree appears as a symbolic element in works such as William S. Burroughs’s Naked Lunch and as a motif in urban decay narratives, reflecting its ubiquity in cities and its reputation as a resilient, often unwanted, presence.
Management considerations
Because of its aggressive spread, many municipalities have listed The Tree of Heaven on "no‑plant" or "invasive species" registries. Effective management typically integrates early detection, public awareness, and coordinated removal programs to prevent establishment in natural habitats.
References
- United States Department of Agriculture, Natural Resources Conservation Service (NRCS). PLANTS Database.
- European and Mediterranean Plant Protection Organization (EPPO) – Ailanthus altissima data sheet.
- Flora of China, Vol. 12, Ailanthus altissima entry.
Note: All information presented is drawn from established botanical and ecological sources.
