Buttonball Tree Platanus occidentalis

American sycamore is a large deciduous tree that may grow 75 to 100 feet tall, is equally as wide, and has a trunk diameter of 10 feet or more. It is one of the largest hardwood trees, by diameter, in North America. This plant is pyramidal in youth, and as it develops it becomes more rounded with an irregular crown and supported by a few large diameter branches. Branches are usually spaced two to four feet apart along the trunk to develop a strong structure. The bark of the tree has a mottled look created by the darker outer layers peeling to expose the lighter inner layers. The bark peels off in patches and the whitened inner bark is the most ornamental trait of this tree. The tree has alternate leaves with 3 to 5 lobes and a coarsely toothed margin. American sycamore is monecious, having both male and female flowers on the same tree.  In spring, very small flowers mature in clusters, typically one cluster to a stalk. The tree produces a round fruit ball borne on a 3 to 6-inch stalk. The interior of the fruit ball is fibrous and has many tiny winged seeds or achenes.

The American sycamore is native to Southeastern Canada and the Central and Eastern United States. This tree reaches its largest size along streams, rivers, and flood plains. It is native to North Carolina and can be found throughout the state.

The genus name, Platanus, is derived from the Greek word, plantanos, and originates from the oriental plane tree or Platanus orientalis. The epithet, occidentalis, means western.  The common name, sycamore, was so named by European settlers because the foliage of this tree looked similar to the sycamore of the British Isles. 

This plant prefers full sun and moist, fertile soils. It is tolerant of clay, sand, loam, alkaline, and wet soils. This plant has moderate drought tolerance. It is pollution tolerant, and has a rapid growth rate, but has numerous pest and disease problems.

A dominant central leader, which typically develops on sycamore, usually assures that the structure of major limbs is desirable. Little corrective pruning is required other than removing the occasional upright, aggressive branches with tight crotches. The leaves of the American sycamore appear similar to a maple leaf; however, the maple leaf is opposite in arrangement and the sycamore is alternate. The lateral lobes of the American sycamore tend to bend downward and inward so that it looks like the leaf is folded or drooping.

When considering this tree in the home landscape, keep in mind that this will be a large tree and will require a large space. It may be used in a recreational area, and its tolerance of urban conditions makes it an option as a street tree. Its ultimate size at maturity and the messy littering of twigs and fruits should be considered.

Seasons of Interest:

Bark:  Winter      Buds:  Winter    Foliage: Summer and Fall    Fruits:  Fall and Winter

Quick ID Hints:

• large deciduous tree, 75 to 100 feet tall and equally as wide, irregular crown
• bark is reddish brown to gray, scaly, at the base, upper bark is light gray, exfoliates to expose the inner bark that is white to cream-colored
• stems zigzag, stout, and orangish-brown
• buds are large, smooth, and best seen during the winter
• alternate, large, green, 3 to 5 lobed leaves, 4 to 9 inches wide, coarse teethed margins, lateral lobes appear folded
• insignificant small male and female flowers, single dense cluster on a stalk
• fruit ball with a fibrous interior and densely packed with seeds or achenes

Insects, Diseases, or Other Plant Problems:  Potential insects include borers, scales, Japanese beetles, caterpillars, and spider mites. Sycamore anthracnose can severely damage foliage and twigs and frequently causes premature leaf drop. This tree is also susceptible to canker, leaf spots, and powdery mildew. This tree creates much litter from its twigs, large leaves, bark, and fruiting balls if planted in the home landscape and will require significant clean-up. This tree is also susceptible to wind damage.  

VIDEO Created by Elizabeth Meyer for "Trees, Shrubs and Conifers" a plant identification course offered in partnership with Longwood Gardens.