70 ELEMENTARY FORESTRY. 



branches before felling. This is practiced to some extent where 

 forests are very valuable. 



The Small Dead Twigs on such trees as spruce, and also 

 the shrubbery which may surround them, are often a very val- 

 uable protection against sun-scald. This also protects from 

 drying winds, which would otherwise, perhaps, sweep through 

 the forests and do them injury. Forest trees seldom do best 

 where they are subject to a strong draft of wind around the 

 trunks. While, under some conditions, it may be desirable to 

 remove the dead branches from trees, yet even if it is decided 

 to do this in the interior of the forest, it is generally best to 

 leave the borders without such pruning in order to protect it 

 from drafts. 



Forest Weed is a term used to signify any growth that 

 may occur in forests which crowds the other growth, and so pre- 

 vents it from developing to the best advantage. It may apply 

 to raspberry bushes, hazel brush, poplars and other similar 

 materials which often come in our forests in the early growth 

 of the plantation; or even to large inferior trees which are in 

 the way of the proper development of the better species. But a 

 tree may at one period of its growth be of much value in a for- 

 est in producing shade and acting as a nurse tree, while later on 

 in its growth, after its usefulness has been completed, it may be 

 regarded as a weed. 



Thinning is the most important part of the forester's art in 

 securing good timber and in reseeding the land. The ideal con- 

 dition in the life of timber trees is to secure a natural crop of 

 seedlings so crowded when young as to increase very rapidly in 

 height and produce slender trunks free from side branches. 

 When this crowding has gone far enough the less valuable and 

 weaker trees should be removed to give the better trees suf- 

 ficient room for their crowns to develop. These remaining trees 

 in the course of a few years will again crowd one another too 

 severely, and this process of removing poorer trees must. then 

 be repeated. Then when the final stand of trees is approaching 

 maturity, thinning should be commenced to let in light and air 

 to produce the conditions under which seedlings develop to best 

 advantage. 



Heavy thinning should be practiced only after very careful 



