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
Tree fork forms in a tree and bark is incorporated into the join, this is referred to as an 'included bark junction' or 'bark inclusion'. A common cause of bark being incorporated into the junction is that the junction is braced by the touching of branches or stems set above that junction (in arboriculture, these branch interactions are termed 'natural braces'). Such included bark junctions can be substantially weaker in strength than normal tree forks, and can become a significant hazard in a tree, particularly when the bracing branches are shaded out or pruned out of the tree. Research has shown that