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Silver birch

 

We have always watched trees in the leafless season, pondered their characters and characteristics.

 

All know the trunk of a birch but distinguishing the silver birch and downy birch from each other is not simple. Against a snowy background the crowns are nicely outlined. The branches of the silver birch are hanging whereas those of the downy birch are upright – only some careful study is needed. Some conclusions can also be drawn from the ground where they grow: silver birches on sandy soils and downy birches on boggy soils. About one third of our forests are birch forests, only pine forests are more abundant.

 

The trunk of a birch is covered by white birch bark, soft to the touch. Shoemakers still used birch bark as a water repellent layer between the soles of boots during the last century. Birch bark has several layers that protect the tree, in summer as well as in winter. The tough white material protects the tree in summer against excessive water vaporisation and scorching sun; on touching it feels refreshingly cool. In cold winter weather it is as if the birch trunk breathes warmth. The birch is in every way equipped for northern climates: the buds are rich in resin, the birch sap rich in sugars – that also protects against freezing; even more than fifty degrees of frost does not damage birches.