THE BIRCH. 341 



shape, and is thin. The branches are often drooping. The 

 root system is weak and shallow. 



It grows quickly from the l)eginning, l)ut rarely reaches a 

 height of 100 feet, generally not l)eyond 70 or 80 feet. Its 

 volume growth is smaller than that of most other important 

 forest trees. Its life seldom exceeds 100 years. 



p. Rcjiroductivc Poiirr. 



Birch begins producing full crops of seed when about 25 

 years old ; they recur every two or three years and sometimes 

 annually, and are heavy. On the whole, the reproductive 

 power by seed is very great. The light seed is easily carried 

 about, and young birch springs up wherever there is room 

 for it, owing to the accommodating power of the species. 



The reproductive power from the stool is weak ; the shoots 

 spring chiefly from the root neck ; the stools are Hal)le to die 

 after two or three rotations. 



f. (Jhararler and ('onijjosiiiu/t of Woodn. 



Owing to its thin crown and great light requirement birch 

 is not well suited for pure woods ; nevertheless it appears 

 pure over extensive tracts in Northern Europe (Eussia, 

 Scandinavia, and Britain), owing to its great reproductive 

 power and accommodating character, which enables it to grow 

 in localities where other species would not thrive, or where 

 it outstrips them. In such localities its preservation is 

 justified. 



In other localities it should be mixed with species with 

 dense crowns, such as beech. It is not so well suited for 

 mixture with conifers, as it injures them Ijy the whip-like 

 action of its slender branches. 



//. Si/h'indlvral Systems. 



High forest, also standards in coppice ; little suited for 

 coppice. Excellent shelter wood over a tender species ; 

 planted in shelter belts and wind breaks. Useful for filling 



