The silver birch, or Betula pendula, is a deciduous European birch tree which is also found in northern Asia, and it is sometimes referred to as European Weeping Birch, or simply Weeping Birch. Growing to around 100 feet (about 30 m) in height, and with a slender trunk, the silver birch may be recognized by its drooping branches and its silver-white bark, which has a paper-like appearance. The leaves are almost diamond-shaped with serrated edges, and turn from bright green to yellow in the fall. As well as being grown for its beauty, the wood, bark and sap of the tree have traditionally been used for a variety of purposes. The sap can be made into beer or wine, the bark has been used to tan leather, and the wood to make small items such as toys or handles.
Silver birch trees have both female and male flowers, known as catkins. These appear in the spring as tiny yellow tails made up of numerous small flower heads. The male catkins release their pollen, which is carried by the wind to fertilize the upright female catkins. When the female catkins ripen at the end of summer or the beginning of fall, their appearance changes and they now hang down in the same way as the males. Each catkin contains many tiny seeds which are released and scattered by the wind.
Some species of fungi form what is called a symbiotic relationship with the silver birch, meaning that both fungus and tree benefit from their association. One such fungus is the traditional toadstool of fairy stories, known as the fly agaric, with its bright red cap and white spots. By way of its connection to the roots of the tree, the fly agaric helps the silver birch take up soil nutrients. The fungus can break down nutrients to make them available for uptake and its presence also creates a larger surface area through which water and useful substances can be absorbed. In return, the silver birch provides sugars for the fungus.
Celtic mythology uses the silver birch to symbolize the process of becoming new and pure. Traditionally, at new year, birch twigs were formed into bundles and used to beat and drive out the spirits belonging to the old year. Birch twigs are still bundled together to make traditional brooms, or besoms, today. There are also natural twiggy tangles which can occur sometimes in the branches of the silver birch, resembling large nests. These are referred to as witches' brooms, but they are caused by a fungus which distorts the growth of the tree.