Birch bark Birch bark Birch bark or birchbark is the bark of several Eurasian and North American birch trees of the genus "Betula". The strong and water-resistant cardboard-like bark can be easily cut, bent, and sewn, which has made it a valuable building, crafting, and writing material, since pre-historic times. Even today, birch bark remains a popular type of wood for various handicrafts and arts. Birch bark also contains substances of medicinal and chemical interest. Some of those products (such as betulin) also have fungicidal properties that help preserve bark artifacts, as well as food preserved in bark containers. Removing birch bark
Cyclocarya female catkins 25–30 cm long at maturity, bearing several small winged nuts with a circular wing 2.5–6 cm diameter right round the nut (instead of two wings at the sides as in "Pterocarya"). Cyclocarya Cyclocarya is a genus of flowering plants in the family Juglandaceae, comprising a single species Cyclocarya paliurus (qing qian liu or wheel wingnut), formerly treated in the genus "Pterocarya" as "Pterocarya paliurus". It is native to eastern and central China. It is a deciduous tree growing to 30 m tall. The foliage is similar to "Pterocarya", with pinnate leaves 20–25 cm long with five to eleven