GROWTH IN HEIGHT. 



55 



tree which excels in it, but also the chance to spread 

 laterally, and so to complete the defeat of its slower 

 rivals by overtopping them. 



ff 

 i 



FIG. 52. FIG. 53. 



A tall clear trunk made by natural pruning, and the base of the same tree. 

 Sitka Spruce in the Olympic Forest Reserve, Washington. 



