Common Names: Ailanthus, Copal tree, Stinking sumac, Varnish tree, Chinese sumac, Paradise-tree
Description: Extensive cloning; allelopathic properties present. Introduced as an ornamental because it grows quickly and is very attractive. It has a medicinal history in Asia where it has been used as an astringent, antispasmodic and parasiticide. Plant extracts are also used as herbicides. It is also a food for honeybees worldwide.
Habit: Deciduous small to large tree; 12-20 m (40-65 ft) tall and 60-100 cm (24-40 in) in diameter; crown wide-spread with multiple branches.
Leaves: Alternate, pinnately compound with 11-30 lance-shaped leaflets, leaves 30-90 cm (1-3 ft) long, 1-5 small gland tipped teeth near the base of each leaflet, dark green above and pale green below, turn yellow in fall; smell like rancid peanut butter when crushed.
Stems: Twigs very stout, light to dark brown, smooth with large V-shaped leaf scars; bark thin, gray to brownish gray, smooth with shallow fissures appearing on older trunks.
Flowers: Small, yellow-green in color, 5 petals; borne in dense clusters near ends of upper branches, male and female flowers on different plants, pollen has an offensive odor; blooms in late spring.
Fruit and seeds: Two-winged, papery, flat samara; reddish when ripe; develop in clusters on female trees in fall, persist in winter, germinate readily, dispersed by wind, birds and water.
Habitat: Shade intolerant; thrives in poor soils; found in disturbed soils, fence rows, fields, roadsides, woodland edges, forest openings and rocky areas; very fast growing.
Reproduction: By seed and vegetatively via root suckering, up to 350,000 seeds produced annually by a single plant.
Similar species: Crushed leaves or broken stems of native sumacs (
Rhus spp.); walnuts (
Juglans spp.) and ash (
Fraxinus spp.); lack rancid peanut butter aroma; leaves lack gland-tipped teeth at base.
Monitoring and rapid response: Monitor edges, paths; hand pull seedlings before taproot develops (<3 months) as taproot fragments may resprout. Resprouts following cutting, girdling, mowing, burning - follow-up treatment required; girdling followed by herbicide most effective; treat cut stumps with an herbicide, all stems in a clone must be treated; basal bark treatment with herbicide provides good root kill, particularly in fall; foliar herbicide treatment is effective on small trees.
Credits: The
Michigan Natural Features Inventory (MNFI) has partnered with MISIN to provide the information in this fact sheet. Species images and/or information were used with permission from "
A Field Identification Guide to Invasive Plants in Michigan's Natural Communities" and "
A Field Guide to Invasive Plants of Aquatic and Wetland Habitats for Michigan.