Soft on the outside. Tough on the inside. On a global scale, this tree, with its fuzzy leaf stalks, shoots and twigs, grows further north than any other broadleaf species.
Mature trees can reach 30m in height, forming a light canopy with elegant, drooping branches. Downy birch is more upright than silver birch and the bark is browner in colour with more obvious horizontal grooves and lacking the papery quality of the silver birch.
Look out for: bark which is grey-white, and triangular-shaped leaves.
Identified in winter by: bark which is white all year round and twigs that are softly hairy to the touch.
Leaves – Triangular in shape but more rounded at the base than silver birch leaves. Leaf stalks are downy, as opposed to hairless on silver birch.
Flowers – Downy birch is monoecious, meaning both male and female flowers (catkins) are found on the same tree. Appearing from April to May, male catkins are long and yellow brown in colour. They hang in groups of two to four at the tips of shoots, like lambs’ tails; while female catkins are smaller, short, bright green and erect.
Fruits – After successful pollination (by wind), female catkins thicken and change colour to a dark crimson. Masses of tiny seeds are borne in autumn and dispersed by the wind.
Where to find downy birch – Found throughout Europe, downy birch tends to grow on damper soils than silver birch and can even tolerate peat bogs and clay.
Its range is more northerly and western than silver birch, and it can grow at higher elevations. Around the world, it can grow further north than any other broadleaf species.
Value to wildlife – Birch woods (which may include downy or silver birch, or both) have a light, open canopy, providing the perfect conditions for grasses, mosses, wood anemones, bluebells, wood sorrel and violets to grow.
Downy birch provides food and habitat for more than 300 insect species. The leaves attract aphids, providing food for ladybirds and other species further up the food chain. They are also a food plant for the caterpillars of many moths, including the angle-shades, buff tip, pebble hook-tip, and Kentish glory. Birch trees are particularly associated with specific fungi, including fly agaric, woolly milk cap, birch milk cap, birch brittlegill, birch knight, chanterelle and the birch polypore (razor strop).
Woodpeckers and other hole-nesting birds often nest in the trunk, while the seeds are eaten by siskins, greenfinches and redpolls.
Mythology and symbolism – In early Celtic mythology, the birch symbolised renewal and purification. Bundles of birch twigs were used to drive out the spirits of the old year, and gardeners still use the birch besom, or broom, to ‘purify’ their gardens. It is also used as a symbol of love and fertility. In Scottish Highland folklore, a barren cow herded with a birch stick would become fertile, and a pregnant cow would bear a healthy calf. The traditions relating to birch are ambiguous. On the positive side it is seen as protective, guarding children against weakness that may overshadow them in early life. At one time however, it was used to whip children (hence ‘birching’), though this probably reflects the need to drive out evil spirits rather than the desire to punish. In the same way, birch twigs were used to ‘beat the boundaries’ of a piece of land. Birch was also the wood traditionally used to make broomsticks for witches, who claimed that the light within the wood helped them fly!
Uses of downy birch – Birch wood is tough and heavy, making it suitable for furniture, handles and toys. It was used to make bobbins, spools and reels for the Lancashire cotton industry; and herbal medicines were made from different parts of the tree. In spring, the rising sap can be used to make refreshing drinks, wines, ales and liqueurs; while the bark is used for tanning leather.
Threats and conservation – Planted birch appears to be susceptible to birch dieback, which is caused by two fungal pathogens, Marssonina betulae and Anisogramma virgultorum. Naturally regenerated birch (that grow from seeds fallen from trees) appears to be less prone to this disease.