Birch Birch A birch is a thin-leaved deciduous hardwood tree of the genus Betula (), in the family Betulaceae, which also includes alders, hazels, and hornbeams. It is closely related to the beech-oak family Fagaceae. The genus "Betula" contains 30 to 60 known taxa of which 11 are on the IUCN 2011 Green List of Threatened Species. They are a typically rather short-lived pioneer species widespread in the Northern Hemisphere, particularly in northern areas of temperate climates and in boreal climates. Birch species are generally small to medium-sized trees or shrubs, mostly of northern temperate and boreal climates. The simple leaves
Terminalia sericea to tall. The bark is a reddish or greyish brown colour and peels away in strips. The bluish-green leaves tend to be clustered at the tips of the branches. They are ovate with entire margins and both the upper and lower surfaces are clothed in silvery hairs. The flowers are white and are borne in short axilliary spikes. They have an unpleasant smell and may be pollinated by flies. The fruit are winged nuts containing a single seed and turn a darker pink colour as they ripen. They may remain attached to the branch for a year and are dispersed