Sycamore, American

A sycamore can grow to massive proportions, typically reaching up to 30 to 40 meters (98 to 130 ft) high and 1.5 to 2 meters (4.9 to 6.6 ft) in diameter when grown in deep soils. The largest of the species have been measured to 51 meters (167 ft), and nearly 4 meters (13 ft) in diameter. The sycamore tree is often divided near the ground into several secondary trunks, very free from branches. Spreading limbs at the top make an irregular, open head. Roots are fibrous. The trunks of large trees are often hollow.

The LEAVES are alternate, palmately nerved, broadly-ovate or orbicular, four to nine inches long, truncate or cordate or wedge-shaped at base, decurrent on the petiole. Three to five-lobed by broad shallow sinuses rounded in the bottom; lobes acuminate, toothed, or entire, or undulate. They come out of the bud plicate, pale green coated with pale tomentum; when full grown are bright yellow green above, paler beneath. In autumn they turn brown and wither before falling. Petioles long, abruptly enlarged at base and inclosing the buds. Stipules with spreading, toothed borders, conspicuous on young shoots, caducous.

The FLOWERS are monoecious, borne in dense heads. Staminate and pistillate heads on separate peduncles. Staminate heads dark red, on axillary peduncles; pistillate heads light green tinged with red, on longer terminal peduncles. Calyx of staminate flowers three to six tiny scale-like sepals, slightly united at the base, half as long as the pointed petals. Of pistillate flowers three to six, usually four, rounded sepals, much shorter than the acute petals. Corolla of three to six thin scale-like petals.

The FRUIT are Brown heads, solitary or rarely clustered, an inch in diameter, hanging on slender stems three to six inches long; persistent through the winter. These heads are composed of akenes about two-thirds of an inch in length. October.

An American sycamore tree can often be easily distinguished from other trees by its mottled exfoliating BARK which flakes off in great irregular masses, leaving the surface mottled, and greenish-white, gray and brown. The bark of all trees has to yield to a growing trunk by stretching, splitting, or infilling; the Sycamore shows the process more openly than many other trees. The explanation is found in the rigid texture of the bark tissue, which lacks the elasticity of the bark of some other trees, so it is incapable of stretching to accommodate the growth of the wood underneath and the tree sloughs it off.

In its native range, it is often found in riparian and wetland areas. The range extends from Iowa to Ontario and Maine in the north, Nebraska in the west, and south to Texas and Florida. The American Sycamore is also well adapted to life in Argentina and Australia and is quite widespread across the Australian continent especially in the cooler southern states such as Victoria and New South Wales. It is said that the Sycamore made up a large part of the forests of Greenland and Arctic America during the Cretaceous and Tertiary periods. It once grew abundantly in central Europe, from where it has now disappeared.