Why is mescaline an internationally controlled substance derived from peyote given exemptions for religious use by indigenous groups in Mexico, and by the pan-indigenous Native American Church in the United States and Canada? What are the intersections of peyote use, constitutional law, and religious freedom? And why are natural populations of peyote in decline so much so that in Mexico, peyote is considered a species needing "special protection"? This fascinating book addresses these questions and many more. It also examines the delicate relationship between "the needs of the plant" as a...