72 PRACTICAL FORESTRY. 



material ; if too late, a tardy development of timber, 

 and future weakness. Too much stress cannot be laid 

 upon the necessity of wise and prudent thinning. 

 All who have practically followed the fortunes of a 

 plantation will have noticed the rapid development 

 of timber after each successive thinning. Where 

 thinning, too, has been neglected, they will have 

 noticed the weak and feeble growth, the lichen- 

 covered stems, the dead and dying trees, and the 

 unhealthy appearance of the whole. Why is this ? 

 Simply because there has been a lack of air and light 

 and insufficiency of foliage to elaborate the sap, and 

 the want of room for the ramification of the root- 

 fibres. Trees, when growing, need air and light and 

 ample room below, otherwise they crush out one 

 another, and the strongest and fittest only survive. 

 Diseases of various kinds prey upon the enfeebled 

 trees, and the result is failure and disappointment. 

 Again, if left too long, they become dependent upon 

 each other for support ; and when this support is 

 removed they feel, like the brute creation, the cold 

 and draughts which follow, growth becomes sluggish, 

 the sap circulates slowly, the elaboration is imperfect, 

 the cells become thickened, and the tree, by epicormic 

 branches, makes an effort to relieve itself from the 

 superabundant sap, and finally succumbs. We have 

 seen large areas of both deciduous trees and conifers 

 suffering from this careless management ; and it is 

 rendered the more lamentable by the impossibility 

 of fully repairing the mischief. 



Where from the earliest period careful thinning has 

 been carried out, very different results are manifest. 



