600 Platanus occidentalisCommon Names: sycamore, American sycamore, buttonwood, American planetree Family: Platanaceae (sycamore Family)
American sycamore is one of the largest trees in eastern North America, often reaching more than 100 ft (30.5 m) in height with a trunk diameter greater than 10 ft (3.1 m). It has a tall straight trunk and a large, open, irregular canopy. The bark on young trees is dark reddish-brown. On older trees, the bark separates and peels off in large thin flakes, revealing the lighter colored inner bark in attractive, irregular patches. The deciduous leaves are alternate, 4-8 in (10.2-20.3 cm) long and wide, with 3-5 lobes, and have long petioles. The flowers are tiny and arranged in dense heads about a half inch in diameter. The fruits are packed in greenish (turning brown) spherical clusters about 1.5 in (3.8 cm) in diameter which hang on stalks 3-6 cm (7.5-15.2 cm) long. The mottled brown, green, gray and white exfoliating bark and the distinctive ball-like fruit clusters, some of which remain on the tree in winter after the leaves have fallen, make the sycamore one of the most well known trees in America.
London planetree (Platanus X acerfolia), a popular street tree throughout the world, is a hybrid between the American sycamore and the oriental planetree (P. orientalis).
American sycamore, Platanus occidentalis, occurs in rich woods and floodplain forests in eastern North America from Maine to Iowa, south to northern Florida and Texas, and in the mountains of eastern Mexico. Sycamore usually grows along streams, sometimes in groves, but more often in association with other bottomland hardwoods such as red maple (Acer rubrum), silver maple (Acer saccharinum), sweetgum Liquidambar styraciflua, river birch (Betula nigra), cottonwood () and willows.
CultureLight: Full sun or light shade. Moisture: Needs considerable soil moisture. Does best in rich, deep, well drained soils, but is tolerant of wet, poorly drained soils. Hardiness: USDA Zones 5 - 9. Propagation: By seed or by hardwood cuttings taken in winter.
Due to their large size and habit of shedding leaves, seed balls, and bark, sycamores are best suited for use in large landscapes. They often are used as street trees, and in public parks. Sycamores tolerate compacted soil and air pollution, and can withstand heavy pruning. They are, however, bothered by several insects and fungus diseases, which may weaken trees, but rarely kill them. London planetree, which is more tolerant of most problems, is often used in cities instead of American sycamore.
The largest hardwood tree in the US is an American sycamore growing in Jeromesville, Ohio that has a trunk over 15 ft (38.1 cm) in diameter! Sycamore is fast growing and can reach 80 ft (24.4 m) in height in 20 years or less. This is a great tree for climbing. Really big ones are sometimes hollow and used by bears for winter dens. The unique seed balls are used in decorative winter arrangements. Native Americans of at least 7 different tribes used infusions of sycamore inner bark for so many ailments that one has to suspect genuine effectiveness.
The tiny hairs on the fruit clusters can irritate the skin and, if inhaled, the respiratory passage. The chaff and dust generated during processing of fruits to extract the seeds is dangerous, and people who do this must wear protective masks. Sometimes the growing roots can clog sewers and damage sidewalks, and fallen leaves can clog drains. American sycamore is a fast growing tree. Don't plant it too close to buildings and utility lines!
Steve Christman 11/20/99; updated 5/14/04