The leaves and flowers help set it apart from other trees or shrubs and make it easy to identify. The simple alternate leaves are ovate, to more or less 7 inches long and 6 inches wide, glabrous, and entire. The long petiole is the same gray-green color and half the length of the leaf. When crushed the leaf gives off an odor that is always described as unpleasant. They are odorless and grow in loose panicles along the branches.
Brown capsules follow the flowers, which bloom all year, and are filled with tiny seeds.
Tree tobacco grows rapidly to 8 feet or higher in one year s time. Lethal as it was tobacco has a long history of medicinal use and N. tabacum was included in the US Pharmacopoeia from 1820 to 1905 as a narcotic, sedative, diaphoretic, and emetic. But all tobaccos were used in the same way for medicinal purposes. The Aztecs used it for nervous complaints and fevers accompanied by chills. Often a poultice of the leaves, which are the medicinal part, was used externally for internal problems.