Tree to 20 m tall, trunk to 1.2 m diameter Leaves: opposite, pinnately compound, stalked, 5 - 12 cm long, 3.2 - 7 cm wide, with three to five leaflets. Flowers: either male or female, found on separate trees (dioecious), borne in clusters, greenish yellow, 3.5 - 4.5 cm long. Fruit: winged (samara), paired, 3.5 - 4.5 cm long, wings narrowly angled (less than 45 degrees). Bark: gray to light brown, becoming deeply furrowed with rounded ridges. Twigs: purple to violet with a whitish waxy coating that is easily rubbed off (glaucous). Leaf scars: wrap around the twig and meet to form a sharp point. Leaflets: light green, elliptic, margin usually coarsely toothed but may be shallowly lobed or non-toothed.

Similar species: The typical variety of Acer negundo has green to reddish brown twigs often covered by a waxy whitish coating (glaucous).

Flowering: late March to early May

Habitat and ecology: Very common and often weedy species in the Chicago Region, occurring in moist woods, flood plains, disturbed areas, and along riverbanks.

Occurence in the Chicago region: native

Notes: This species was once used as a street tree because it adapts to many soil types. It is no longer planted due to its weak wood, pest and disease problems, and messy fruit.

Etymology: Acer is derived from a Latin word meaning sharp, which refers to the hardness of the wood. Negundo comes from the Sanskrit name for Vitex negundo, which has leaves resembling those of A. negundo. Violaceum means violet-colored, referring to the stems.

Author: The Morton Arboretum