BIRCH

(Betula), genus of hardy trees and shrubs of N. temperate zone to 70° N., B. alba being the common species, forming large forests in Ru ia, has a silvery cuticle, easily peeled, small irregularly serrated leaves, and the fruit has membra nous wings to a ist dispersal. The bark (from which an its oil is obtained), wood, and sap are applied to various uses.