Betula papyrifera
| Betula papyrifera | |
|---|---|
 |
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| Paper Birch | |
| Scientific classification | |
| Kingdom: | Plantae |
| (unranked): | Angiosperms |
| (unranked): | Eudicots |
| (unranked): | Rosids |
| Order: | Fagales |
| Family: | Betulaceae |
| Genus: | Betula |
| Subgenus: | Betula |
| Species: | B. papyrifera |
| Binomial name | |
| Betula papyrifera Marsh. |
|
Betula papyrifera (Paper Birch, also known as Paper Birch, American White Birch and Canoe Birch) is a species of birch native to northern North America.
Contents |
[edit] Description
It is a medium-sized deciduous tree reaching 60 feet tall (18m) (exceptionally to 130 feet) (40m) with a trunk up to 32 inches diameter (0,8m). The bark is white, commonly brightly so, flaking in fine horizontal strips, and often with small black marks and scars. In individuals younger than five years, the bark appears brown with white lenticels, making the tree much harder to distinguish from other trees. The leaves are alternate, ovate, 1-5 in. long and 2-4 in. broad, with a doubly serrate margin. The leaf buds are conical and small. They are green-colored with brown edges. The flowers are wind-pollinated catkins 1.5 in. long growing from the tips of twigs. The fruit matures in the fall. The mature fruit is composed of numerous tiny winged seeds packed between the catkin bracts. They drop between September and spring.
[edit] Distribution
Betula papyrifera has a wide range. It is found in interior (var. humilus) and south-central (var. kenaica) Alaska and in all provinces and territories of Canada, except Nunavut, as well as the northern continental United States, south to Pennsylvania and Washington, with small isolated populations further south in mountains to North Carolina, New Mexico, and Colorado. The most southerly stand in the Western United States is located in Lost Gulch in the City of Boulder Mountain Parks, an isolated Pleistocene relict that most likely reflects the southern reach of boreal vegetation into the area during the last Ice Ages.[1]
[edit] Ecology
Betula papyrifera is a pioneer species; for example, it is frequently an early invader after fire in Black Spruce Boreal forests.[2] B. papyrifera requires high nutrients and sun exposure. The bark is highly weather-resistant. Often, the wood of a downed paper birch will rot away leaving the hollow bark intact.[3] Birch bark is a winter staple food for moose. The nutritional quality is poor, but is important to wintering moose because of its sheer abundance. Although white-tailed deer consider Birch a "secondary-choice food", it is an important dietary component. In Minnesota, white-tailed deer eat considerable amounts of paper birch leaves in the fall. Snowshoe hares browse paper birch seedlings.
[edit] Conservation
The species is considered vulnerable in Indiana, imperiled in Illinois, Virginia, West Virginia and Wyoming, and critically imperiled in Colorado and Tennessee. When used in landscape planting, it should not be planted near black walnut as the chemical juglone, exuded from the roots of black walnut, is very toxic to white birch.
[edit] Uses
Betula papyrifera has a soft, yet moderately heavy, white wood. It makes excellent high-yielding firewood if seasoned properly. Its bark is an excellent fire starter, burning at high temperatures even when wet.
While a paper birch does not have a very high overall economic value, it is used in furniture, flooring, popsicle sticks[4] and oriented strand board. The sap is boiled down to produce birch syrup. Its name reflects the use of the tree's bark, primarily by Native Americans, for a writing material.[citation needed] Panels of bark can be fitted or sewn together to make cartons and boxes (a birchbark box is called a wiigwaasi-makak). The bark is also used to create a durable waterproof layer in the construction of sod-roofed houses.[3]
[edit] Culture
Betula papyrifera is the Provincial tree of Saskatchewan and the State tree of New Hampshire.
[edit] References
- ^ Cooper, David J. (Spring 1984) (PDF). Ecological Survey of the City of Boulder, Colorado Mountain Parks. City of Boulder Parks and Recreation Department. p. 16. http://www.bouldercolorado.gov/files/openspace/pdf_gis/IndependentResearchReports/249_Cooper_David_Ecological.pdf. Retrieved 2011-09-16.
- ^ Hogan, C. Michael (2008). "Black Spruce (Picea mariana)". GlobalTwitcher. http://globaltwitcher.auderis.se/artspec_information.asp?thingid=44751. Retrieved 2011-09-16.
- ^ a b Ewing, Susan (April 1, 1996). The Great Alaska Nature Factbook. Portland, Oregon: Alaska Northwest Books. ISBN 9780882404547.
- ^ Bellis, Mary. "Popsicle - The History of the Popsicle". About.com. http://inventors.about.com/library/inventors/blpopsicle.htm. Retrieved 2011-09-16.
[edit] External links
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Wikimedia Commons has media related to: Paper Birch |
- Flora of North America: Betula papyrifera
- Flora of N.Amer- RangeMap: Betula papyrifera
- http://www.cnr.vt.edu/DENDRO/dendrology/syllabus/factsheet.cfm?ID=14 (best picture of young bark)
- http://www.fs.fed.us/database/feis/plants/tree/betpap/all.html (most detailed data)
- http://www.rook.org/earl/bwca/nature/trees/betulapap.html (concise outline details)
- Betula
- Trees of continental subarctic climate
- Flora of Subarctic North America
- Trees of humid continental climate
- Trees of Alaska
- Flora of Northern Canada
- Trees of Alberta
- Flora of the Rocky Mountains
- Trees of the Great Lakes region (North America)
- Trees of the Northwestern United States
- Trees of the Northeastern United States
- Trees of the Plains-Midwest (United States)
- Trees of Canada
- Trees of Saskatchewan
- Trees of Ontario
- Trees of Michigan
- Flora of Massachusetts
- Flora of North Dakota
- Trees of Idaho
