PLANT COVERING OF THE EARTH. 169 



without access to which the plant cannot do its 

 best work. To develop a forest of very tall trees 

 demands long ages. If we cut a wood away and 

 permit the trees to grow again, they will develop 

 with much shorter stems than the parent wood. 

 Only slowly does the forest climb again to its 

 primeval elevation. Hence it comes about that 

 the forests of the New World are so much higher 

 than those of the Old. In Europe there are hardly 

 any woods, at most but scant patches, which have 

 escaped the axe. Almost all the timber is of the 

 second growth. 



The close relation of forests to the needs of man 

 make it essential that in any country, which is to 

 be kept in the best condition for human occupa- 

 tion, a large share of its woodlands should be 

 spared destruction. When civilized men first 

 came to this country, they found all the regions 

 to which they had access in the state of dense 

 woods. It was a difficult matter to clear away 

 these forests in order to reduce the soil to the uses 

 of the plough. Thus the farmers have got into 

 the habit of looking upon the woods as enemies to 

 be driven away. The result of this is that the de- 

 struction of the forests has proceeded with great 

 rapidity ; indeed, with a recklessness which jeop- 



rapidii 



