Birch is the name of any 
tree of the genus Betula, in the family Betulaceae, closely related to the 
beech/
oak family, Fagaceae.  These are generally small to medium-size 
trees or 
shrubs, mostly of northern 
temperate climates.  The simple 
leaves may be toothed or lobed.  The fruit is a small 
samara, although the wings may be obscure in some species.
In times past, commercial oil of wintergreen (methyl salicylate[?]) was made from the sweet birch, Betula lenta.
Birches of eastern North America include:
- Betula allegheniensis -- yellow birch
- Betula glandulosa -- dwarf birch
- Betula lenta -- sweet birch (or black birch)
- Betula michauxii -- Newfoundland dwarf birch
- Betula nigra -- river birch
- Betula papyrifera -- white birch (or paperbark birch)
- Betula populifolia -- gray birch
- Betula pumila -- swamp birch
- Betula pendula -- Silver birch, is native to Europe and parts of Asia.
Above; bark of Siver birch (Betula pendula)
Above; timber of Silver birch (Betula pendula)
See also; Trees of Britain, Trees of the world
 
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