Tree of Heaven, Ailanthus, Chinese Sumac, Stinking Shrub
Kingdom: Plantae, Division: Tracheophyta, Class: Magnoliopsida, Order: Sapindales, Family: Simaroubaceae, Genus: Ailanthus, Species: Ailanthus altissima · Simaroubaceae (Quassia family) · Pinnately compound, deciduous
Species
Ailanthus altissima
Leaf Type
Pinnately compound, deciduous
Family
Simaroubaceae (Quassia family)
Shape
Lanceolate leaflets with an asymmetrical base, featuring 1 to several glandular teeth near the base
Size
The pictured compound leaf is approximately 8-10 inches long; mature compound leaves on the tree typically range from 1 to 3 feet in length with individual leaflets measuring 2-6 inches long.
Margin
Entire on most of the leaflet edge, but distinctly toothed (serrate) near the base with prominent glandular dots on the teeth
Arrangement
Alternate arrangement of compound leaves along the stem, with leaflets arranged oppositely or sub-oppositely along the rachis
Rarity
Very Common (frequently considered a persistent and invasive weed in urban and disturbed environments)
Color & Pattern
Dark green upper surface with a lighter green underside; the rachis and central stem are a dark brown to purplish tone due to pressing and natural pigmentation; looks healthy and evenly colored without variegation
Venation Pattern
Pinnate venation with a prominent central midrib and ascending lateral veins on each leaflet
Texture & Surface
Smooth (glabrous) upper surface with a slightly matte to semi-glossy finish; papery texture typical of a pressed herbarium specimen
Description
Ailanthus altissima is a fast-growing deciduous tree known for its ability to rapidly colonize disturbed sites. It features large, tropical-looking compound leaves, smooth gray bark that becomes vertically fissured with age, and large clusters of yellowish-green flowers followed by papery winged seeds called samaras. The entire plant, especially when crushed, emits a strong, distinctive odor often compared to rotting peanuts or cashew fruit.
Key Features
Pinnately compound leaves with distinctive glandular teeth at the base of each leaflet; foul-smelling foliage when crushed; large heart-shaped leaf scars on twigs; fast growth rate
Habitat
Highly adaptable, thriving in disturbed areas, urban environments, along roadsides, railway tracks, and forest edges; prefers full sun and tolerates poor soils and drought
Geographic Range
Native to central and northern China and Taiwan; widely introduced and currently invasive across North America, Europe, and parts of Australia and Asia
Condition Notes
The specimen is in good, intact condition as a pressed botanical sample, showing well-preserved leaflet structure and coloration with minor tape residue from mounting
Interesting Facts
Tree of Heaven was famously the subject of the best-selling novel A Tree Grows in Brooklyn. It is the primary host plant for the invasive spotted lanternfly (Lycorma delicatula), creating significant concerns for agriculture and forestry.
Medicinal & Uses
Used in traditional Chinese medicine for various ailments including dysentery and cold symptoms, though rarely used in modern Western herbalism due to toxicity risks; formerly planted as an urban street tree due to pollution tolerance
Ecological Role
Acts as an aggressive invasive species that outcompetes native vegetation through high seed production, rapid growth, and the release of allelopathic chemicals that inhibit the growth of surrounding plants
Similar Species
Native sumacs (Rhus spp., such as Staghorn Sumac) and Black Walnut (Juglans nigra); distinguished by the glandular teeth at the base of Ailanthus leaflets and the unpleasant odor of crushed leaves
Foraging Tips
Easily identified by looking for large compound leaves with foul-smelling foliage, prominent leaf scars, and clusters of papery samaras in late summer and autumn; most commonly found growing in vacant lots and highway margins
Toxicity Warning
Mildly to Moderately Toxic; the sap and bark can cause contact dermatitis in sensitive individuals, and ingestion of leaves or roots can lead to gastrointestinal distress and systemic symptoms