Birch tar

Birch bark pitch made in a single pot: The birch bark is heated under airtight conditions, the final product consists of tar and the ashes of the bark.

Modern way of producing birch bark tar in a single pot: The birch bark is heated under airtight conditions, the final product consists of tar and the ashes of the bark.

Birch tar or birch pitch is a substance (liquid when heated) derived from the dry distillation of the bark of the birch tree.

Compounds[edit]

It is compounded of phenols such as guaiacol, cresol, xylenol and creosol.

Uses[edit]

Birch tar was used widely as an adhesive as early as the late Paleolithic or early Mesolithic era. It has also been used as a disinfectant, in leather dressing, and in medicine.^{[citation needed]}

Ends of fletching of arrows were fastened with birch-tar and birch-tar-and-rawhide lashings were used to fix the blade of axes in the Mesolithic period.

Russia leather is a water-resistant leather, oiled with birch oil after tanning. This leather was a major export good from 17th and 18th century Russia, as the availability of birch oil limited its geographical production.^[1] The oil impregnation also deterred insect attack and gave a distinctive and pleasant aroma that was seen as a mark of quality in leather.

Birch tar oil is an effective repellent of gastropods.^[2] The repellent effect lasts about two weeks.^[2] The repellent effect of birch tar oil mixed with petroleum jelly applied to a fence lasts up to several months.^[2]

Birch tar oil is also used in perfumery as a base note to impart leather, tar, smoky, and wintergreen notes.

References[edit]

^ "Production of Russia Leather" (PDF). The Honourable Cordwainers' Company. 1807.
^ ^a ^b ^c Lindqvist I., Lindqvist B., Tiilikkala K., Hagner M., Penttinen O.-P., Pasanen T. & Setälä H. (2010). "Birch tar oil is an effective mollusc repellent: field and laboratory experiments using Arianta arbustorum (Gastropoda: Helicidae) and Arion lusitanicus (Gastropoda: Arionidae)". Agricultural and Food Science 19(1): 1-12. doi:10.2137/145960610791015050.