Sweetgum (Liquidambar) is a genus of four species of flowering plants in the family Altingiaceae, though formerly often treated in the Hamamelidaceae. They are all large, deciduous trees, 25-40 m tall, with palmately lobed leaves arranged spirally on the stems.
The leaves turn multiple colors in the fall. The flowers are small, produced in a dense globular inflorescence 1-2 cm diameter, pendulous on a 3-7 cm stem. The fruit is a woody multiple capsule 2-4 cm diameter (popularly called a "gumball"), containing numerous seeds.
The woody biomass is classified as hardwood. In more northerly climates, sweetgum is among the last of trees to leaf out in the spring, and also among the last of trees to drop its leaves in the fall.
The genus was much more widespread in the Tertiary, but has disappeared from Europe due to extensive glaciation in the north and the Alps, which has served as a blockade against southward migration.
It has also disappeared from western North America due to climate change, and also from the unglaciated (but nowadays too cold) Russian Far East. There are several fossil species of Liquidambar, showing its relict status today.
See Also: florist, florists, flower