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. 

Although this majestic tall tree is called tree-of-heaven, it is regarded as an invasive species that is capable of displacing native trees, poisoning root systems, damaging sewer lines with its roots, and producing a sap that can cause heart imflammation.

ORIGIN

First introduced from its native China into the U. S. in 1751, it has since been planted throughout American cities because it is fast-growing, resistant to pollution, and provides ample shade. However, it is now considered quite invasive.

HABITAT

Forest, forest edges, shrublands, thickets, disturbed areas

LIFE CYCLE

Flowering occurs in early summer, when large clusters of yellowish flowers develop above the leaves, Fruit produced on the female trees are tan to reddish, single winged, papery seeds, called samaras. They may remain on the tree throughout late fall.