CHAP. IV.] 



The Food of Trees 



79 



manured land) the solutions are richer than in land of inferior 

 quality. Proceeding from this point of view, Ebermayer made 

 the following classification of trees with regard to their relative 

 power of transpiration or relative requirements as to soil- 

 moisture, by tabulating them according to the percentage of 

 water the fresh leaves contained as compared with their total 

 weight. 



Taken on the whole, these scientific conclusions correspond 

 fairly accurately with the knowledge acquired by sylvicultural 

 experience, although at the same time certain kinds of trees, 

 like Acacia, Birch, and Pines, are better fitted than other trees 

 to accommodate themselves to conditions not exactly satisfying 

 their normal requirements with regard to moisture. It cannot 



