254 PRUNING. 



branch as would keep it vital ; and the invariable result 

 was a diminution of the thickness of layer of wood in 

 the stem, in some cases the year immediately succeed- 

 ing the operation, and in others two or three years 

 subsequently ; but in every case, just in proportion to 

 the extent of pruning done, so were the unfavourable 

 results. By way of further experiment, the writer 

 denuded some Scots pines of about 6 to 8 feet in 

 height of all their pins or leaves, leaving only the 

 terminal shoots covered ; and the results were that, 

 although making annual top-growths of from 1 2 to 14 

 inches the year previous, the next season they made 

 only from 3 to 5 inches. The defoliating process was 

 carried on two years longer (three years in all), during 

 which time the top-growth still continued to decrease ; 

 but owing to the writer leaving the scene of experi- 

 ments, he cannot record further results, though the 

 probability is that they would all soon perish. 



The top-growth of a number of trees operated upon 

 was likewise materially influenced by the foreshorten- 

 ing practice of pruning, but not so much so as by 

 pruning off the lateral branches. Those most severely 

 pruned of their lateral branches suffered most in their 

 top leader. 



The above experiment was made with a view of 

 showing how the top-growth of a tree is influenced by 

 reducing the side branches, and the results shown 

 were, that the top-growth is not promoted by reducing 

 or confining the side branches, but through shelter, by 

 protecting the top of the tree from storm, tempest, and 

 blighting winds, and by deep and congenial soil, by 

 which the whole structure of the tree is nourished and 

 built up. This is very obvious from what may be 

 seen in the natural forest, where trees may be found 



