No. 561] 



DARWINISM IN FORESTRY 



545 



it expressed in such fullness and so strikingly as in the 

 forest. The forest is a natural breeding place in which 

 constantly only the trees best adapted to the climate and 

 the situation are allowed to remain. In the forest only 

 the conquerors in the struggle for existence are the ones 

 which produce seed in abundance. During a seed year 

 the dominant and co-dominant trees produce seed in large 

 quantities; the intermediate trees, which may properly 

 be called the candidates for suppression, participate but 

 little, and then only in exceptionally good seed years, 

 while the oppressed and suppressed do not bear seed at 

 all. "With what rigidity, then, must the natural selection 

 go on in a forest, if we consider first what a small per- 

 centage of trees in a stand of the same generation come to 

 be conquerors in the struggle for existence; second, the 

 great age reached by trees ; third, the numerous genera- 

 tions of trees that have succeeded each other in the same 

 forest ; and fourth, the relatively limited capacity of tree 

 seeds for dissemination. With each generation the for- 

 est trees must become more and more delicately adjusted 

 and adapted to the given conditions of growth. The new 

 generation inevitably arises from seed sown by the best 

 developed trees, from those which have withstood the long 

 and intense battle not only against Nature alone, but 

 against Nature in the presence of competitors. Of this 

 possibly only 1 per cent, or less will reach maturity and 

 be able to continue the species. No wonder, therefore, 

 that in spite of search for new species all over the world 

 so few forest trees have been successfully introduced into 

 new countries and so little progress has been made with 

 the artificial improvement of them. So perfect is the nat- 

 ural selection in the forest, so fine is the adjustment be- 

 tween the environment and the forest trees, that it is al- 

 most impossible for man to approach it. I do not mean 

 the introduction of trees for park purposes or breeding 

 new varieties for some other purpose than timber; I have 

 in mind only the establishment of natural forests and the 

 production of timber. 



