Although silver birch (B. pendula) has become very popular, to the extent that it has even been called Finland’s national tree, in their own local environment at least as many Finns have come across the white or downy birch, familiar but largely unknown.
Familiar it must be because it is currently the most common tree species in Finland; unknown, perhaps, because it is not easy to distinguish from the silver birch, particularly further north. Birch species hybridise, but distinguishing between these two species is made more difficult by the variability of the white birch. Naturally appearing forms and mutations are numerous, including the red birch (f. rubra), the pole birch (f. columnaris) and shrubby birch (f. fruticosa). An important subspecies is that found on the fells of Lapland, subsp. czerepanowii.
Compared with silver birch, the white birch usually grows on wetter soils, even on peat bogland. It withstands trimming better than silver birch so is used in birch hedges in northern parts, especially in Sweden. Its common use in plantings can be explained by how easy it is to transplant young trees from the wild. White birch is less long-lived than silver birch, but even when old it is a beautiful tree. The trunk remains white longer than that of the silver birch, and its branches don’t usually droop at any stage. In winter the shoots can be used to help in recognition: the white birch has smooth shoots, the silver warty ones; in summer the leaves can help, those of the silver being triangular or diamond-shaped, while those of the white birch are more round.