Cinchona in quinology to examine the contents of these components in assays. The yields of quinine in the cultivated trees were low and it took a while to develop sustainable methods to extract bark. In the meantime Charles Ledger and his native assistant Manuel collected another species from Bolivia. Manuel was caught and beaten by Bolivian officials leading to his death but Ledger obtained seeds of high quality which were offered to the British who were uninterested, leading to the rest being sold to the Dutch. The Dutch saw its value and multiplied the stock. The species later named as "Cinchona
Bark beetle economic impact. In undisturbed forests, bark beetles serve the purpose of hastening the recycling and decomposition of dead and dying wood and renewing the forest. A few species are aggressive and can develop large populations that invade and kill healthy trees and are therefore known as pests. Bark beetles of the family Scolytidae feed and breed between the bark and the wood of various tree species, including spruces. More than 20 species feed on weakened, dying, or dead spruce, fir, and hemlock. Most restrict breeding area to one part of the tree: twig, branch, stem, or root collar. Some breed