Birch tree ID by bark
Birch trees can be identified by their distinctive bark. Here are six species or varieties. Silver Birch is widespread in Britain, Down Birch is more common in the Scottish Highlands and the others are introduced species or varieties planted in parks, gardens or urban settings for their striking bark.
The horizontal lines on Birch tree bark are lenticels. These are pores through which the tree can breath. The dead cork cells of the bark are filled with a waxy substance that makes them resistant to decay and stops the transmission of air and water.
Some trees such as planes, birches and cherries regularly shed their bark. Cherries and Birches shed bark in strips and become banded in appearance as the old and new bark can be seen at the same time. Bark shedding, known as exfoliation, may be a sign of stress but in Cherries and Birches exfoliation may be a controlled way of getting rid of a build up of parasites. Alternatively, in those species that photosynthesise through their bark, it may be a way of replacing old, light blocking layers with new more effective layers. The whitest bark is found in species from the far north. It is thought that this is to reflect the winter sun and prevent unhealthy warming. For more information on bark click HERE
Birch tree ID by bark – Here are photos of the bark of six Birches – Silver, Downy, West Himalayan, Paper-bark, Ermin’s and River bark