Sassafras trees grow from 15–35 m (50–120 feet) tall and 70–150 cm (2.5–6 feet) in diameter, with many slender branches, and smooth, orange-brown bark. The branching is sympodial. The bark of the mature trunk is thick, red-brown, and deeply furrowed. The wood is light, soft, weak, and brittle. All parts of the plants are very fragrant. The species are unusual in having three distinct leaf patterns on the same plant, unlobed oval, bilobed (mitten-shaped), and trilobed (three pronged; rarely the leaves can be five-lobed). They have smooth margins and grow 7–20 cm long by 5–10 cm broad. The young leaves and twigs are quite mucilaginous, and produce a scent similar to lemons when crushed. The tiny, yellow flowers are five-petaled and bloom in the spring; they are dioecious, with male and female flowers on separate trees. The fruit are blue-black, egg-shaped, 1 cm long, produced on long, red-stalked cups, and mature in late summer.
Steam distillation of dried root bark produces an essential oil consisting mostly of safrole that once was extensively used as a fragrance in perfumes and soaps, food and for aromatherapy. The yield of this oil from American sassafras is quite low and great effort is needed to produce useful amounts of the root bark. Commercial "sassafras oil" generally is a by-product of camphor production in Asia or comes from related trees in Brazil. Safrole is a precursor for the clandestine manufacture of the drug ecstasy, and as such, its transport is monitored internationally.
For most of the above mentioned animals, sassafras is not consumed in large enough quantities to be important. Carey and Gill rate its value to wildlife as fair, their lowest rating.
The roots of Sassafras can be steeped to make tea and were used in the flavoring of root beer until being banned by the U. S. Food and Drug Administration (FDA). Laboratory animals that were given oral doses of sassafras tea or sassafras oil that contained safrole developed permanent liver damage or various types of cancer. In humans, liver damage can take years to develop and it may not have obvious signs.
In 1960, the FDA banned the use of sassafras oil and safrole in foods and drugs based on the animal studies and human case reports. Several years later, the sale of sassafras oil, roots, or tea for human consumption was prohibited by law. Subsequently, both Canada and the United States have passed laws against the sale of any consumable products (beverages, foods, cosmetics, health products such as toothpaste, and others) that contain more than specific small amounts of safrole.
Sassafras tea can also be used as blood thinner.
Sassafras was a commodity prized in Europe as a cure for Gonorrhea.