Liquidambar styraciflua aka Sweetgum

American sweet gum, Liquidambar styraciflua, is a deciduous tree in the family Altingiaceae. It grows wild from Connecticut south to Florida and west to Illinois and Texas. Its range continues through the mountains of Mexico into Central America, reaching Honduras and El Salvador. In the wild it favours moist bottomlands, stream banks and swampy woods that flood each year. The name refers to the fragrant resin that seeps from wounds in the bark.

In gardens the tree usually reaches 60 to 80 feet (18 to 24 m) tall and 35 to 60 feet (11 to 18 m) wide. Old wild trees can pass 100 feet (30 m), and a few records reach 150 feet (45 m). Young trees form a neat pyramid on a single straight trunk. With age the crown becomes oval or rounded. The grey-brown bark grows deep furrows and ridges as the tree matures. On some trees, two-year-old twigs carry corky wing-like ridges.

The glossy, star-shaped leaves have five to seven pointed, toothed lobes and a long stalk. They measure 4 to 8 inches (10 to 20 cm) across and smell resinous when crushed. Unlike maple leaves, they sit alternately on the stem. Autumn colour varies from tree to tree. It may mix yellow, orange, red, burgundy and purple, and the leaves hang on late. Small yellow-green flowers open in spring. Male flowers stand in upright clusters, while female flowers hang in round heads. The female heads ripen into spiny brown balls about 1 to 1.5 inches (2.5 to 4 cm) across. These gumballs hold small winged seeds and stay on the tree into winter.

Sweet gum needs full sun for its best colour, though it copes with light shade. It prefers deep, moist, fertile soil that is neutral to acid. It accepts clay, loam and sand, and it tolerates wet ground. Alkaline soil causes yellowing leaves from chlorosis, so plant only where the pH is 7 or lower. Sources rate it hardy in USDA zones 5 to 9, or up to 10, and H6 in the UK. Young trees and early spring growth can suffer cold and frost damage. Northern gardeners should choose stock grown from northern seed.

This is a fine shade tree for lawns, parks and campuses with plenty of room. It grows at a moderate to fast rate. The seeds feed goldfinches in winter, and the leaves host imperial and regal moth caterpillars. The resin, called storax, has served as chewing gum, incense, perfume and folk medicine. The timber goes into furniture, veneer, plywood and boxes.

The tree has few serious problems. Webworms, caterpillars, borers and scale can appear in some areas. Leaf spots, wood rot, bleeding necrosis and honey fungus may also occur. The shallow, vigorous roots can lift pavements, so keep trees 8 to 10 feet (2.5 to 3 m) from kerbs. Falling gumballs make a mess and can trip people on hard surfaces. Seedlings may spring up in nearby beds and form thickets. Established trees resent root damage from building work. No hazards are known, and the resin is chewed as a natural gum.