70 



the boundaries of its territorial distribution has 

 been used as an argument against the correct- 

 ness and adaptability of Mayr's zone forma- 

 tion, the fact being altogether forgotten 

 that every species of wood can also be grown 

 some little distance beyond its territorial 

 home : 



1. If it is kept at a distance from the other 

 species of timber which would otherwise naturally 

 outgrow it. 



2. If the fructification and maturity of seed 

 is not required. English Elm ( Ulmus campestris) 

 is an example of this. 



3. If the same climatic conditions are afforded 

 it beyond its territorial distribution which it 

 enjoys within such limits, to which must be 

 added that by our ability to choose sites, soil, 

 and the method and degree of protection, &c., 

 we are in a position to modify the conditions 

 of temperature in a positive or negative direction. 

 The best data, therefore, as regards the climatic 

 demands of any particular species, and the start- 

 ing-point for the further study of its sylvicultural 

 management, are to be found in the zone of 

 vegetation in which it grows and can be raised. 

 It is only in localities where seed and plants 

 cost almost nothing and where trained foresters 

 are absent that the dictum of ignorant growers 

 may be followed, which, to speak the truth. 



