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Birchbark is used to make birch-tar, a particularly fine tar. The terms tar and pitch are often used interchangeably. However, pitch is considered more solid, while tar is more liquid. Traditionally, pitch that was used for waterproofing buckets, barrels and ships was drawn from pine. It is used to make cutler's resin.
Birch bark tar use as an adhesive began in the Middle Paleolithic. Neanderthals produced tar through dry distillation of birch bark as early as 200,000 years ago. [6] A 2019 study demonstrated that birch bark tar production can be a simpler, more discoverable process by directly burning birch bark under overhanging stone surfaces in open-air conditions. [7]
Birch tar. Tar was used as seal for roofing shingles and tar paper and to seal the hulls of ships and boats. For millennia, wood tar was used to waterproof sails and boats, but today, sails made from inherently waterproof synthetic substances have reduced the demand for tar. Wood tar is still used to seal traditional wooden boats and the roofs ...
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A trunk of a birch, with part of bark cut out A Russian birch bark letter from the 14th century Birchbark shoes. Birch bark or birchbark is the bark of several Eurasian and North American birch trees of the genus Betula. For all practical purposes, birch bark's main layers are the outer dense layer, white on the outside, and the inner porous ...
Resin is usually collected by causing minor damage to the tree by making a hole far enough into the trunk to puncture the vacuoles, to let sap exit the tree, known as tapping, and then letting the tree repair its damage by filling the wound with resin.
Pine tar is a form of wood tar produced by the high temperature carbonization of pine wood in anoxic conditions (dry distillation or destructive distillation). The wood is rapidly decomposed by applying heat and pressure in a closed container; the primary resulting products are charcoal and pine tar .