Birch bark

Birch bark or birchbark is generally understood to be the bark of the Paper Birch tree ("Betula papyrifera"), or sometimes of related species such as Gray (Wire) Birch ("Betula populifolia").

The strong and water-resistant cardboard-like bark can be easily cut, bent, and sewn, which made it a valuable building, crafting, and writing material, since pre-historic times. Even today birch bark remains a popular material 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.

Collection and storage

Birch bark can be removed fairly easily from the trunk or branches, living or recently dead, 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, the phloem, kills the tree by preventing the flow of sap to the roots.

To prevent it from rolling up during storage, the bark should be spread open and kept pressed flat.

Working

Birch bark can be cut with a sharp knife, and worked like cardboard. For sharp bending, the fold should be scored (scratched) first with a blunt stylus.

Fresh bark can be worked as is; bark that has dried up (before or after collection) should be softened by steaming, by soaking in warm water, or over a fire.

Uses

Birch bark was a valuable construction material in any part of the world where birch trees were available. Containers like wrappings, bags, baskets, boxes, or quivers were made by most societies well before pottery was inventedFact|date=July 2008. Other uses include:

*In North America, the native population used birch bark for canoes, wigwams, scrolls, ritual art (birch bark biting), maps (including the oldest maps of North AmericaFact|date=July 2008), torches, fans, musical instruments, clothing, and more.
*In Scandinavia and Finland, it had many uses, including roofs, boxes, casks and buckets, fishing implements, shoes (as used by the Egtved Girl), etc..
*In Russia, many birch bark documents have survived from the Middle Ages.
*In the Indian civilisation birch-bark, along with dried palm leaves, replaced parchment as the primary writing media. The oldest known Buddhist manuscripts (some of the Gandharan Buddhist Texts), from Afghanistan, were written on birch barkFact|date=July 2008.

Birch bark also makes an outstanding tinder, as the inner layers will stay dry even through heavy rainstorms. To render birch bark useless as tinder, it must be soaked for an extended period.

ee also

* Mazinibaganjigan (Ojibwa birch bark decorative designs)
* Wiigwaasabak (Ojibwa birch bark scrolls)
* "" entry in Wiktionary

References

*"The Algonquin Birchbark Canoe" () by David Gidmark. [http://www.woodencanoe.net/shop/book/thealgonquin.html]

External links

* [http://www.wwmag.net/barktorc.htm The Birch Bark Torch] , a "Wilderness Way Magazine"'s article by Kevin Finney.
* [http://www.nativetech.org/brchbark/ Birchbark articles] from the "NativeTech" site.
* [http://www.extension.umn.edu/specializations/environment/components/birchbark1.html Birch and Birch Bark] , an article by John Zasada at an University of Minnesota site.
* [http://www.northhousefolkschool.com/classes/BoatBuilding.htm Birch Bark Canoe Building Courses] at the North House Folk School, Minnesota.
* [http://www.algonquinsofpikwakanagan.com/Culture%20birch%20bark%20canoe%202004.htm Birch Bark Canoe] page on the site of the Algonquins of Pikwàganagàn.
*http://www.davidmosesbridges.com (Traditional Wabanaki Birch-Bark Craft)