Betula pendula

Silver Birch
Silver Birch in winter
Scientific classification
Kingdom:	Plantae
Division:	Magnoliophyta
Class:	Magnoliopsida
Order:	Fagales
Family:	Betulaceae
Genus:	Betula
Subgenus:	Betula
Species:	B. pendula
Binomial name
Betula pendula Roth.

Silver Birch (Betula pendula) is a widespread European birch, though in southern Europe it is only found at higher altitudes. Its range extends into southwest Asia in the mountains of northern Turkey and the Caucasus. The closely related Siberian Silver Birch (B. platyphylla) in northern Asia and Sichuan Birch (B. szechuanica) of central Asia are also treated as varieties of Silver Birch by some botanists, as B. pendula var. platyphylla and B. pendula var. szechuanica respectively (see birch classification).

It is a medium size deciduous tree, typically reaching 15-25 m tall, exceptionally up to 30 m, with a slender crown of arched branches with drooping branchlets. The bark is white, often with black diamond-shaped marks or larger patches at the base. The shoots are rough with small warts, and hairless, and the leaves 3-6 cm long, triangular with a broad base and pointed tip, and coarsely serrated margins. The flowers are wind-pollinated catkins, produced before the leaves in early spring, the small (1-2 mm) winged seeds ripening in late summer on 3-5 cm long catkins.

It is distinguished from the related Downy Birch (B. pubescens, the other common European birch) in having hairless, warty shoots (hairy, without warts in Downy Birch), and whiter bark often with scattered black fissures (greyer, less fissured, in Downy Birch). It is also distinguished cytologically, Silver Birch being diploid (with two sets of chromosomes), whereas Downy Birch is tetraploid (four sets of chromosomes). The two have subtle differences in habitat requirements, with Silver Birch found mainly on dry, sandy soils, and Downy Birch more common on wet, poorly drained sites such as clay soils and peat bogs. Many North American texts treat the two species as conspecific (and cause confusion by combining the Downy Birch's alternative vernacular name 'White Birch', with the scientific name B. pendula of the other species), but they are regarded as distinct species throughout Europe.

It is often planted as a garden and ornamental tree, grown for its white bark and gracefully drooping shoots. In Scandinavia and other regions of northern Europe, it is grown for forestry. It is sometimes used as a pioneer and nurse tree elsewhere.

Silver Birch is Finland's national tree. Occasionally one uses leafy, fragrant boughs of Silver Birch to gently beat oneself in a sauna. The boughs are called vihta or vasta. This has a relaxing effect on the muscles.

Land of the Silver Birch is a traditional Canadian folk song, though the birch referred to is actually a different species, Paper Birch Betula papyrifera.

See also

List of Lepidoptera which feed on Birches

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  Silver Birches at Stockholm University
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  Silver Birch bark
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  Silver Birch seed catkin

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  Silver Birch - from Thomé Flora von Deutschland, Österreich und der Schweiz 1885
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  Silver Birch: foliage of the cut-leaf cultivar 'Laciniata'
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  Betula pendula at night in winter