It is Halloween once again, and if there’s a perfect tree for the Halloween season it is the American sycamore. In October, when the trees in the James River watershed begin to change color and shed their leaves, the ghostly trunk of the American sycamore (Platanus occidentalis) stands out among the sea of orange and red. Sycamores are also called buttonwood or buttonball trees because of the 1-inch balls that hang from the tree through the winter months and fall each spring.
While many trees shed their bark by crumbling bit-by-bit, the American sycamore is among a grouping of Exfoliating Bark Trees. You can recognize a sycamore by its exfoliating bark that looks almost white amid the darker tree trunks. Think of it as a mummy losing its wrappings or a zombie tree and you’ll get the picture. This peeling bark is the result of the tree’s growth process. Unlike most other trees that have bark that stretches or infills as the trunk grows, the sycamore’s rigid bark lacks elasticity and flakes off to accommodate the growth of new wood. Arborists believe that trees that shed their bark have environmental advantages and are better able to get rid of pests, fungus and bacteria.
Found throughout the eastern US, the sycamore is one of the largest trees in the eastern forest. They can reach a height of 70 to 100 feet with a canopy spread of 60 to 80 feet. While surveying for the Kanawha Canal, George Washington recorded a sycamore tree with a trunk that measured 45 feet in circumference. Also monstrous in size are its leaves, the largest of any North American tree, which often measure up to 8 inches across.
Keeping with the Halloween tree theme, the sycamore is susceptible to anthracnose fungus which can affect stem growth and form “witches’ brooms” or leafless clusters of sprouts that form on limbs. For this reason, anthracnose resistant hybrids of the sycamore, like the London planetree, are better suited to an urban environment as a shade tree.
This large tree is most often found in a riparian setting, so the next time you’re near the James River, look for a ghostly pale tree trunk. You might by surprised by how many American sycamore trees you see.