TENDING OF OPEN WOODS. 221 



SECTION III. TENDING OF OPEN WOODS FOR THE 

 PRODUCTION OF LARGE TIMBER. 



1. The Theory. 



In the foregoing section it has been shown how 

 thinnings should be conducted, if the principal part of 

 a wood the dominant trees ^are to be given increased 

 space and enjoyment of light, followed by increased 

 increment, without, however, interrupting the leaf- 

 canopy to such an extent as to affect injuriously the 

 continued activity of the soil. Under this method of 

 treatment, the one aim acts antagonistically to the 

 other, and it is by no means easy to conciliate the two 

 interests. Hence the problem presents itself, whether 

 the better portion of the dominant trees cannot be 

 more completely isolated, while the soil is protected by 

 other means. There are other considerations which 

 press the subject upon the attention of the forester. 

 Under the ordinary system, as described above, the 

 production of large-sized timber demands a high rota- 

 tion, and any measures which tend to reduce the latter 

 must be welcome. Experience has shown that by 

 isolating the trees, timber of a certain size can be pro- 

 duced in little more than half the time required under 

 the method of continuously crowded woods. 



Another point is, that many, and more especially the 

 light-demanding species, have a natural tendency to 

 open out, or to form large crowns. 



It is of additional importance that under a system of 

 heavy thinnings, considerably larger intermediate yields 

 are obtained early in the rotation. This, in conjunction 



