Small to large tree with very large, one to
2-foot leaves not opposite
each other on the branches. Leaves compound, made up of
about a dozen long, narrow, pointed leaflets opposite each other
on the leafstalk. Leaflets untoothed, except for a single pair
of teeth at the base. Young leaves in spring tinged red. Flowers
small, greenish-yellow, in clusters in mid-June. Fruits are samaras, flat, dry wings encasing a seed
(maple "helicopters" are paired samaras). Tree-of-heaven
samaras are reddish, in clusters, not pairs, and the seed is in the
invasive alien species that is increasingly invading the
woodlands of the eastern United States. We
are trying to reduce or eliminate this undesired species, but it is
still far too common in the Park's woodlands, particularly
along the edges.
The flowers and fruits are good identifiers. In leaf it is easily identified as it has the largest compound
leaves, with the most leaflets, of any tree in the Park.
Small specimens can easily be confused with staghorn sumac, but that
species has leaves that are toothed along their entire edge,
hairy twigs, and very different flowers and fruits.