The tree can also be found in several more temperate regions of Australia.
Silver birch (Betula pendula), is native to Europe and parts of Asia, though southern Europe, it is found only at higher altitudes. Its range extends into Siberia, China, and southwest Asia in the mountains of northern Turkey, the Caucasus, and northern Iran. It has been introduced into North America, where it is known as the European white birch. The tree can also be found in several more temperate regions of Australia. In 1988 the Finish people voted silver birch as their national tree.
Silver birch is a medium-sized deciduous tree that owes its common name to the white peeling bark on the trunk. The twigs are slender and often pendulous and the leaves are roughly triangular with doubly serrated margins and turn yellow in autumn before they fall.
The tree is planted in parks and gardens and is used for products such as joinery timber, firewood, tanning, racecourse jumps, and brooms. Parts of the tree are used in traditional medicines, and the bark contains triterpenes, which have been shown to have medicinal properties.
The implausible paleness of silver birch trunks is an adaptation helping trees that lack the shade of dense foliage to keep trunks cool in the day and night sunshine of the northern summer, or in the glare of snow. The bark of young birches is baby-bum smooth. However, as the tree matures thick and dark corky patches appear near the ground in order to protect the trees from fire. The thickened bark can be boiled to extract a tarry resin that inspired the Latin name Betula, from the same linguistic stock as bitumen. Some 5000 years ago the bark resin was used as an antiseptic chewing gum.
By day, the distinctive monochrome pattern of snow-clad birch forests is dazzling and disorientating, but during long boreal nights the moonlit ghostly forms take on an eerie power. Birches are bound in the folk tales of northern peoples and many superstitions and rituals surround the tree.
Birch sap, which rises in the last throes of winter, just before bud burst, is taken as an early spring tonic. Tapping is done by drilling or stabbing a small hole in the southern side of the tree and inserting a tube. The resulting fluid looks and tastes like sweetened water. It does contain some important vitamins and minerals, although not really enough to warrant its mythical reputation for health-giving properties.
Silver birch trees have been revered for centuries for their ability to renew and purify – and to subvert spells and sorcery. Some Finns still place birch saplings are in doorways as symbolic protection. Birch twigs are sometimes infected with the fungus called Taphrina which causes them to branch chaotically into tousled nests called ‘witches’ brooms’ and these have supernatural associations in some cultures.
The birches life partner is Amanita muscaria, the fly agaric – a mushroom – whose fruiting bodies are scarlet with white sprinkles – the archetypal mushrooms of every fairy tale. Fly agarics contain a cocktail of mind-bending hallucinogens around which all manner of shamanistic rituals have evolved, particularly amongst Siberian tribes and the Saami people of northern Finland and Sweden.
However, the fly agaric’s psychoactive ingredients are not completely broken down in the body, but excreted. This offers the enticing possibility – and a spot of social bonding – by drinking the pre-drugged urine of others. However, whether this practice was really as widespread as historic travellers, who seem to be the common source of all the shamanistic pee-drinking stories have so eagerly reported is debatable.