162 SOME GENERAL CONSIDERATIONS 



system to a greater effort, thus causing an increase in the 

 size of the stock. 



The early bearing habit of dwarfed trees may be ex- 

 plained on the theory that the diminished supply of sap 

 tends to weaken the whole tree. Now the object of every 

 plant, one may say, is to reproduce its kind; and when 

 it finds itself weakening it seems to hasten this process of 

 reproduction, in order to make sure that it may leave 

 progeny before it dies. The dwarfed and weakened trees 

 thus blossom and set fruit before their normal mates; 

 and are correspondingly shorter lived, due to this weaken- 

 ing, in consequence of the mechanical restriction of the 

 food supply. 



Hardiness in Nursery Stock. Many questions are being 

 asked at the present time if it is advisable to buy nursery 

 stock a considerable distance from where it is to be planted, 

 and especially if stock grown in the south is as resistant as 

 northern grown stock to the rigorous winter conditions. 

 While no specific experiments appear to have been tried 

 to determine this point many observations from practical 

 experience have been made. Nursery trees of every kind 

 have been shipped far and wide and have therefore been 

 tried under all kinds of conditions. Insofar as hardiness 

 is concerned there appears to be no difference due to the 

 locality in which the tree may be grown. 



There are other considerations, however, which often 

 make it advisable to secure stock as near as possible to the 

 place where it is to be planted. The danger of introducing 

 insects and diseases is greater when buying from a distance, 

 and there is less chance to become personally acquainted 



