Betula lenta as long as the tree lives, but the individual bark layers become indiscernible after roughly 250 years of age. "Betula lenta" was used commercially in the past for production of oil of wintergreen before modern industrial synthesis of the oil; the tree's name reflects the wintergreen scent of the shoots. The sap flows about a month later than maple sap, and much faster. The trees can be tapped in a similar fashion, but must be gathered about three times more often. Birch sap can be boiled the same as maple sap, but its syrup is stronger (like molasses). The leaves
Jesuit's bark Jesuit's bark Jesuit's Bark, also known as cinchona bark, as Peruvian Bark, and as China Bark, is a former name of the most celebrated specific remedy for all forms of malaria. It is so named because it was obtained from the bark of several species of the genus "Cinchona", of the Rubiaceae family, that have been discovered at different times and are indigenous in the Western Andes of South America and were first described and introduced by Jesuit priests who did missionary work in Peru. Other terms referring to this preparation and its source were "Jesuit's Tree", "Jesuit's Powder" and