Malaria saved the lives of thousands of workers and helped develop the methods used in future public-health campaigns against the disease. The first effective treatment for malaria came from the bark of cinchona tree, which contains quinine. This tree grows on the slopes of the Andes, mainly in Peru. The indigenous peoples of Peru made a tincture of cinchona to control fever. Its effectiveness against malaria was found and the Jesuits introduced the treatment to Europe around 1640; by 1677, it was included in the London Pharmacopoeia as an antimalarial treatment. It was not until 1820 that the active ingredient, quinine,
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,