Sassafras is a genus of three extant and one extinct species of deciduous trees in the family Lauraceae, native to eastern North America and eastern Asia. The genus is distinguished by its aromatic properties, which have made the tree useful to humans.
Sassafras trees grow from 9–35 m (30–115 ft) tall with many slender sympodial branches, and smooth, orange-brown bark or yellow bark. All parts of the plants are fragrant. The species are unusual in having three distinct leaf patterns on the same plant: unlobed oval, bilobed (mitten-shaped), and trilobed (three-pronged); the leaves are hardly ever five-lobed. Three-lobed leaves are more common in Sassafras tzumu and Sassafras randaiense than in their North American counterparts, although three-lobed leaves do sometimes occur on Sassafras albidum. The young leaves and twigs are quite mucilaginous, and produce a citrus-like scent when crushed. The tiny, yellow flowers are generally six-petaled; Sassafras albidum and Sassafras hesperia are dioecious, with male and female flowers on separate trees, while Sassafras tzumu and Sassafras randaiense have male and female flowers occurring on the same trees. The fruit is a drupe, blue-black when ripe.
Early European colonists reported that the plant was called winauk by Native Americans in Delaware and Virginia and pauane by the Timucua. Native Americans distinguished between white sassafras and red sassafras, terms which referred to different parts of the same plant but with distinct colors and uses. Sassafras was known as fennel wood (German Fenchelholz) due to its distinctive aroma.
Many Lauraceae are aromatic, evergreen trees or shrubs adapted to high rainfall and humidity, but the genus Sassafras is deciduous. Deciduous sassafras trees lose all of their leaves for part of the year, depending on variations in rainfall. In deciduous tropical Lauraceae, leaf loss coincides with the dry season in tropical, subtropical and arid regions. In temperate climates, the dry season is due to the inability of the plant to absorb water available to it only in the form of ice.
The leaves, bark, twigs, stems, and fruits are eaten by birds and mammals in small quantities. For most animals, sassafras is not consumed in large enough quantities to be important, although it is an important deer food in some areas. Carey and Gill rate its value to wildlife as fair, their lowest rating. Sassafras leaves and twigs are consumed by white-tailed deer and porcupines. Other sassafras leaf browsers include groundhogs, marsh rabbits, and American black bears. Rabbits eat sassafras bark in winter. American beavers will cut sassafras stems. Sassafras fruits are eaten by many species of birds, including bobwhite quail, eastern kingbirds, great crested flycatchers, phoebes, wild turkeys, gray catbirds, northern flickers, pileated woodpeckers, downy woodpeckers, thrushes, vireos, and northern mockingbirds. Some small mammals also consume sassafras fruits.
Sassafras albidum is often grown as an ornamental tree for its unusual leaves and aromatic scent. Outside of its native area, it is occasionally cultivated in Europe and elsewhere. The durable and beautiful wood of sassafras plants has been used in shipbuilding and furniture-making in North America, in Asia, and in Europe (once Europeans were introduced to the plant). Sassafras wood was also used by Native Americans in the southeastern United States as a fire-starter because of the flammability of its natural oils found within the wood and the leaves.
Sassafras oil has also been used as a natural insect or pest deterrent, and in liqueurs (such as the opium-based Godfrey's), and in homemade liquor to mask strong or unpleasant smells. Sassafras oil has also been added to soap and other toiletries. It is banned in the United States for use in commercially mass-produced foods and drugs by the FDA as a potential carcinogen.
In modern times, the sassafras plant has been grown and harvested for the extraction of sassafras oil. It is used in a variety of commercial products or their syntheses, such as the insecticide synergistic compound piperonyl butoxide. These plants are primarily harvested for commercial purposes in Asia and Brazil.