4 GEORGE P. BURNS 



season. Figured on this basis, from the beginning of the vege- 

 tation period to the time of the experiment it was possible to 

 determine that the approximate amount of water transpired from 

 each tree was as follows: 



No shade 21 x cc. 



Half shade 8 x cc. 



Full shade x cc. 



That is, the seedling in no-shade used 21 times, and the 

 seedling in half-shade used 8 times as much water as the one 

 in full-shade. 



The questions naturally arise which was the best tree, which 

 had the greatest amount of ash, what was the chemical composi- 

 tion of these trees? 



Trees harvested July 31 were about 8 to 10 weeks old. The 

 average green weight of the trees based upon the weight of 

 500 seedlings in the case of the "no-shade" and ''half-shade" 

 trees and upon the weight of 1000 seedlings in the "full-shade" 

 trees, was as follows : 



Green weight Dry weight 



No shade 0.304g- 0.063gr 



Half shade 0.166 0.034 



Full shade 0.090 0010 



The dry weight of the plant produced in "no-shade" was a 

 little more than six times as great as that produced in "full- 

 shade," and the plant produced in "half-shade" was almost 

 three and a half times as heavy in dry weight as the "full-shade" 

 plants only about one-half as heavy as the "no-shade" plant. 



The ash content of the plants was next determined and is 

 here given in percentage of dry weight only. This showed that 

 the total ash content was: 



No shade. 8.29% 



Half shade 9.35% 



Full shade 10.20%, 



The nitrogen content for the three trees in percentage of dry 

 weight was: ■ 



