It is also known as cascara, from the Spanish cáscara, meaning "husk", and is different from cascara sagrada tea, a powerful plant-based laxative.
It is now thought that the black bottle refers to cascara (Rhamnus purshiana) mixed with milk of magnesia, a diuretic which was commonly given to admitted patients.
Rhamnus frangula | Rhamnus purshiana | Rhamnus californica |
The larvae feed on various trees and shrubs, including Rhamnus purshiana, Holodiscus discolor, Sambucus species and Symphoricarpos albus.