CHAPTER IV. 



THINNING. 



IN self-sown natural forests, and even in arti- 

 ficially raised plantations, we find in the first 

 stage as many as from fifty to a hundred plants 

 occupying the space required by one mature tree. 

 This is as it should be, for the plants being 

 close together, can develop only upwards towards 

 the light, and thereby acquire at the outset that 

 tall straight form which results in the greatest 

 percentage of timber, and generally in the most 

 valuable timber ; but it is evident that before any 

 one of these fifty or a hundred trees, as it may 

 be, can reach maturity, the others must be all 

 removed. 



Natural forests of gregarious trees thin them- 

 selves ; that is, there is a struggle for existence, in 

 which the weakest succumb at every stage, thereby 

 making room for the development of the dominant 

 trees for another stage. This is done by every 

 second or third tree rising above its fellows, and 

 these dominant trees, spreading out their branches 



