Cinchona Totaquina required a minimum of 70% crystallizable alkaloids of which at least 15% was to be quinine with not more than 20% amorphous alkaloids. There are at least 24 species recognized by botanists. There are likely several unnamed species and many intermediate forms that have arisen due to the plants' tendency to hybridize. Cinchona Cinchona is a genus of flowering plants in the family Rubiaceae containing at least 23 species of trees and shrubs. They are native to the tropical Andean forests of western South America. A few species are reportedly naturalized in Central America, Jamaica, French Polynesia, Sulawesi, Saint
Birch bark from live trees is harmful to tree health and should be avoided. Instead, it can be removed fairly easily from the trunk or branches of dead wood, by cutting a slit lengthwise through the bark and pulling or prying it away from the wood. The best time for collection is spring or early summer, as the bark is of better quality and most easily removed. Removing the outer (light) layer of bark from the trunk of a living tree may not kill it, but probably weakens it and makes it more prone to infections. Removal of the inner (dark) layer,