Similar Species for: Ailanthus altissima (Mill.) Swingle
Juglans spp.
Ailanthus may be confused with other trees having compound leaves and many leaflets; particularly two native trees Black Walnut (Juglans nigra L.), Butternut (Juglans cinerea L.). The leaf margins of these trees have small teeth, while those of Ailanthus are smooth. The gland-tipped leaflet lobes are unique to Ailanthus, as is the foul odor produced by crushed foliage and scraped bark. In winter, Ailanthus may be distinguished by the stout twigs, large leaf scars with numerous bundle scars, and false end buds.
Black walnut and butternut produce large round and oval nuts, respectively, encased in fleshy husks that produce a distinct odor. Both develop deeply ridged and fissured bark. The nuts are prized by wildlife and leaves are larval food for many moths and butterflies.
Rhus spp.
Tree of Heaven may also be confused with some native species of sumac (Rhus spp.). Staghorn Sumac (Rhus typhina L.) and Smooth Sumac (Rhus glabra L.) have toothed leaflets while those of Ailanthus are smooth. Winged Sumac (Rhus copallinum L.) leaflets are entire or nearly so, and the leaf has a narrow strip of leaf tissue running up the stem between the leaflets. Sumacs have a more shrublike form. The small, red, round fruits appear in large, upright, conical clusters and are enjoyed by wildlife.
Landscape Alternatives
These native plants are suitable substitutes for Ailanthus altissima in the landscape.
Black Walnut (Juglans nigra) has compound foliage and produces large, tasty nuts. Black walnut is beneficial for all kinds of wildlife including mammals, birds, butterflies, and moths.
Sumacs (Rhus spp.) are large shrubs that grow quickly and don’t mind poor soil. The compound foliage turns blazing red colors in fall, and the pyramidal clusters of flowers and showy red fruit are attractive to bees, butterflies, and birds.
Black Locust (Robinia pseudoacacia) grows quickly, has compound leaves, and showy fragrant clusters of white flowers. It will grow well in poor soil.
Hoptree or Wafer Ash (Ptelea trfoliata) is a small tree with fragrant flowers and showy clusters of winged seed.
White Ash and Blue Ash (Fraxinus americana and F. quadrangulata) have compound foliage, large clusters of winged seeds, and good fall color. White ash cultivar ‘Autumn Purple’ is seedless. Attracts birds and butterflies.