Coca – not to be confused with coconuts or with cacao, the source of chocolate - is a large bush or small tree native to northwestern South America. Cocaine extracted from the leaves found favor among personages as diverse as Sigmund Freud and Ulysses S. Grant as it was once used as a component of various tonics, patent medicines and even a popular wine. Coca leaves are still widely used in this corner of South America for a variety of purposes by the indigenous tribes of the region. 

Sources:

Plotkin, Mark J. Amazon: What Everyone Needs to Know®. Oxford University Press, 2020. 

Plowman, Timothy. “The Ethnobotany of Coca.” Advances in Economic Botany, Volume 1, Sept. 1984, pp. 62–111. 

Prance, Ghillean T., et al. Ethnopharmacologic Search for Psychoactive Drugs. Synergetic Press, in Association with Heffter Research Institute, 2018. 

Schultes, Richard Evans., and Albert Hofmann. Plants of the Gods. Vandermarck, 1979.