10 



A PRIMER OF FORESTRY. 



and take up from the soil water and certain mineral sub- 

 stances which the tree needs 

 in its growth. Second, the 

 trunk, stem, or bole, which 

 supports the crown and sup- 

 plies it with mineral food 

 and water from the roots. 

 (See fig. 4.) Third, the 

 crown itself, with its net- 

 work of branches,buds, and 

 leaves, in which all the food 

 taken up by the tree from 

 the soil and air is worked 

 over and made ready to 

 assist in the growth of 

 the whole plant. (See figs. 

 5-7 and PI. IV.) The 

 crown has more to do with 

 the life of the tree than its 

 other parts, for the most 

 important processes in the 

 reproduction of the tree and 

 the digestion of its food 

 take place in the crown. 

 For this reason, and be- 

 cause we can control its 

 shape and size more easily 

 and directly than that of 

 the roots or trunk, the 

 crown is of special inter- 



Fio.4._TrunksoftwoKedFirs. The 6St tO tbe fester. It IS 



figure of a man between them gives an almost CXClusi Vely with the 



idea of their great size, which, how- crowns that he has to deal 



ever, is not unusual. Olympic Forest . 



Reserve, Washington. HI tending a Crop of trees 



