- Ailanthus altissima is a rapidly growing, typically small tree up to 80 ft. (24.4 m) in height and 6 ft. (1.8 m) in diameter. It has large leaf scars on the twigs.
- Foliage is one of the best identifying characteristics for this species. The leaves are pinnately compound and 1-4 ft. (0.3-1.2 m) in length with 10-41 leaflets. Ailanthus altissima resembles native sumac and hickory species, but it is easily distinguished by the glandular, notched base on each leaflet.
- Species is dioecious and flowering occurs in early summer when large clusters of yellow flowers develop above the foliage.
- Fruit produced on female plants are tan to reddish, single winged and can be wind or water-dispersed.
- Ecological Threat
- Ailanthus altissima forms dense, clonal thickets which displace native species and can rapidly invade fields, meadows, and harvested forests. This invasive tree species is extremely tolerant of poor soil conditions and can even grow in cement cracks. Ailanthus altissima is not shade tolerant, but easily invades disturbed forests or forest edges causing habitat damage. Introduced as an ornamental, it was widely planted in cities because of its ability to grow in poor conditions. Management and control efforts for this species continue across the United States at great economic cost.