July 17. 1916 Influence of Calcium and Magnesium on Plant Growth 597 



Table III shows the analysis of the plants reported in Table II. The 

 results here reported are the average of four determinations from dupli- 

 cate pots. 



From Table III it can be seen that the alfalfa is a heavier feeder on 

 calcium and magnesium than is wheat, and that the percentages and the 

 total amounts removed by the plants tend to increase with the increase 

 in application, except where the calcium and magnesium are applied in 

 the artificially prepared carbonates, in which case the lowest application 

 is sufficient to inhibit growth and retard germination. 



Throughout all the series the general tendency was for the calcium 

 and magnesium content of the plants to increase with the increase in 

 application. Wheeler (39) found that when magnesium was applied in 

 the form of the sulphate the crop showed the ratio of magnesium oxid to 

 calcium oxid to be as i to 1.13, but when magnesium was not present in 

 the fertilizer the ratio of magnesium oxid to calcium oxid was i to 2.7. 



TABLE III. Analyses of wheat and alfalfa series A and B 



WHEAT STRAW 



WHEAT ROOTS 



ALFALFA ROOTS 



Pots i, 2, 21, and 22 were extracted sand and received no calcium and magnesium. 



