BIRCHES. 203 



ported as being valuable for many of the purposes for which 

 pine timber is commonly used. 



Uses. The Certinensis Poplar has been tried largely in 

 this section and has proved to be a good quick growing tree for 

 prairie planting. In some localities, however, it has been infested 

 with a borer which has occasionally done much injury and led 

 to the impression that it is not so hardy as the Cottonwood. 

 The foliage seems to resist the attacks of the leaf fungus 

 t>etter than the Cottonwood. 



Bircli Family. 



Genus BETUXA. 



Flowers monoecious, apetalous, appearing before or with 

 the leaves; the staminate in long pendulous catkins; stamens 

 2; the pistillate in erect cylindrical catkins; ovary naked, 2- 

 celled. Fruit a small nut surrounded by a wing and covered 

 by the enlarged scale of the catkin, ripening in autumn. 

 Leaves alternate, simple, dentate or serrate. Trees or shrubs 

 with watery juice. A large genus represented by many species. 

 The bark contains a resinous balsamic oil sometimes used in 

 tanning- leather. In parts of this country and Canada the 

 bark and leaves of various birches are esteemed as domestic 

 remedies for diseases of the skin, for rheumatism and gout. 

 An oil obtained from the inner bark by distillation is also 

 used externally for the same purpose. The sweet sap of many 

 species is used as a beverage and is sometimes made into 

 wine. 



Propagation. By seeds, which should be sown when 

 gathered or stratified over winter and sown in the spring and 

 the seedlings given some shade during the first season. The 

 varieties are propagated by budding, grafting and inarching 

 on the parent species. 



