Tree of Heaven (also known as Stinking Sumac, Chinese Sumac, Copal Tree)
Plantae > Tracheophyta > Magnoliopsida > Sapindales > Simaroubaceae > Ailanthus > Ailanthus altissima · Simaroubaceae (Quassia family) · Pinnately compound (odd- or even-pinnate), deciduous
Species
Ailanthus altissima
Leaf Type
Pinnately compound (odd- or even-pinnate), deciduous
Family
Simaroubaceae (Quassia family)
Shape
Overall leaf compound, large; individual leaflets are lanceolate to ovate-lanceolate with a characteristic thumb-like glandular lobe or notch near the base.
Size
Entire compound leaf can reach 1 to 3 feet (30-90 cm) or more in length; individual leaflets typically measure 2 to 6 inches (5-15 cm) long.
Margin
Mostly entire along the upper length, but featuring 1 to 4 small glandular teeth or lobes near the leaflet base on both sides.
Arrangement
Alternate arrangement along the stem; leaflets arranged oppositely or sub-oppositely along the central rachis.
Rarity
Very Common (Invasive pest species in urban and disturbed environments across North America and Europe).
Color & Pattern
Upper leaf surface is medium-to-dark green, lower surface is slightly paler. Emerging young growth often exhibits a reddish, bronze, or brownish tinge as seen on the developing central leaf.
Venation Pattern
Pinnate venation on individual leaflets, with clear primary midrib and secondary lateral veins branching toward the margins.
Texture & Surface
Smooth (glabrous) to slightly puberulent upper surface, soft-textured; features small circular raised glands on the underside of the basal teeth.
Description
Tree of Heaven is a fast-growing deciduous tree that can reach heights of up to 80-100 feet. It is characterized by exceptionally large compound leaves, smooth light-gray bark resembling melon rind, and reddish-brown emerging spring foliage. When crushed or bruised, the leaves release a distinctive, unpleasant odor often compared to rancid peanut butter or burnt rubber. The tree reproduces aggressively through wind-dispersed samaras and spreading root suckers, often forming dense monoculture thickets.
Key Features
Glandular teeth/lobes at the base of each leaflet, smooth margins above the base, foul odor when crushed, and reddish-bronze tinged new growth.
Habitat
Disturbed urban areas, roadside margins, alleyways, forest edges, railway lines, and vacant lots. Highly adaptable to poor soils, drought, air pollution, and high salinity.
Geographic Range
Native to northeast and central China and Taiwan. Widely naturalized and invasive across temperate zones worldwide, including North America, Europe, Australia, and South America.
Condition Notes
The specimen shows active spring growth with healthy, glossy green foliage and fresh bronze-tinted new shoots. Minor insect chewing holes are visible on a few lower leaflets, but overall leaf health is Excellent.
Interesting Facts
Introduced to the US as an ornamental in 1784, it is famously featured in the classic novel 'A Tree Grows in Brooklyn' due to its resilience in harsh urban settings. It releases allelopathic chemicals (ailanthone) into the soil to inhibit the growth of surrounding plants.
Medicinal & Uses
Historically used in Traditional Chinese Medicine (bark and roots) to treat ailments like dysentery and asthma, though high doses can be toxic. In modern forestry, it is generally considered an aggressive weed rather than a crop tree.
Ecological Role
High ecological disruption as an invasive species. Outcompetes native plant communities using rapid growth and allelopathic root secretions. Serves as a primary host plant for the invasive Spotted Lanternfly (Lycorma delicatula).
Similar Species
Staghorn Sumac (Rhus typhina - has sharply serrate margins), Black Walnut (Juglans nigra - serrate margins, fragrant nut smell), and Smooth Sumac (Rhus glabra - serrate margins, red fruit clusters). Tree of Heaven is distinguished by its basal glands and smooth leaflet margins.
Foraging Tips
Not recommended for foraging due to bitter taste and mild toxicity. Look for the distinct basal glands on the underside of leaflet bases and smell a crushed leaf to confirm identification.
Toxicity Warning
Moderately Toxic. Leaves, sap, and bark contain irritants that can cause contact dermatitis, myocarditis, and gastrointestinal distress if ingested. Handlers should wear gloves when removing.