Feb. I-. 1919 Effect of Barium and Strontium on Plant Growth 189 



Table V. — Effect of sirontinm nitrate on the growth of winter wlieat — Fourth series 



The results obtained^ in the analysis of the grain for nitrogen, protein, 

 phosphorus, and potassium are interesting (Table VI). It will be seen 

 that with the addition of strontium nitrate there is a decided increase 

 in the nitrogen content of the grain and a decrease in the phosphorus, 

 while the potassium content remains practically constant. 



Table VI. — Percentage of nitrogen, protein, phosphorus, and potassium contained in 

 the grain produced in each of the foregoing experiments 



Having obtained unusual results in the yields and in the nitrogen con- 

 tent of the grain in the previous series of experiments, another, the fifth, 

 series of pot experiments, similar to the ones that have been described, 

 was carried out. This series was planned as a further check on the 

 effect of strontium carbonate on the growth and the nitrogen content 

 of wheat. The amount of strontium carbonate added to each pot and 

 the yields of grain and straw produced are given in Table VII. 



The seeds in pots 9 and 10 came up, and the stunted plants struggled 

 for existence for the greater part of the time the other plants in this 

 series v/ere making a complete growth. The plants never reached a 

 height of more than 10 inches, thus showing that strontium can not 

 replace calcium in the growth of plants. 



