Radermachera sinica, also called china doll, serpent tree or emerald tree, is an evergreen tree in the family Bignoniaceae, native to the subtropical mountain regions of southern China and Taiwan. It can reach heights of up to 30 m tall and a trunk diameter of 1 m. The leaves are bipinnate, 20 to 70 cm long and 15 to 25 cm broad, divided into numerous small glossy green leaflets 2 to 4 cm long. The flowers are white, trumpet-like, about 7 cm long, and resembling a large Bignonia flower in shape. The specific name sinica means "from China".