CHOICE OF SPECIES. 5 



3. Exposure to damage by external causes. 



4. Faculty for preserving or even improving the 



fertility of the soil. 



To which may be added, 



5. Desirability, or otherwise, of a periodical change 



of species. 



1. Suitability of the Species for the Objects of 

 Management. 



The varying objects of management have been indi- 

 cated on page 99 of Volume I. Whatever, in any 

 special case, they may be, the species must be selected 

 so as to do them full justice. 



If the object is to grow produce of a definite descrip- 

 tion, the species must be capable of yielding it ; it would 

 be useless to grow Yew for hop poles, or Poplar for 

 naval construction. Where the objects of management 

 are governed, or influenced, by existing forest rights 

 demanding timber or firewood of a particular species, 

 that tree must be grown. If, on the other hand, third 

 persons are entitled to trees of certain species, should 

 they happen to appear on the area, the owner would 

 not voluntarily cultivate them. 



Where the object is to produce the greatest possible 

 quantity of material per unit of area, that species must 

 be selected which produces the highest average annual 

 increment.* 



In gauging the financial desirability of a species, the 

 quantity and quality of the produce, as well as the 

 expense of rearing it, must be taken into account. In 



* See page 166 of Volume I. 



