Aug. 28, 1916 



Effect on Plant Growth of Sodium Salts 



867 



Table V. — Results of experiment 5 (October, 1914), giving the effect of sodium chlorid in 

 soil on the germination of wheat seedlings 



60 

 SO 

 40 

 SO 



ao 

 /o 

 00 



/ 



S 6 7 / <? S 



>SER/E& A/UMBERS 



Fig. 7. — Diagram of the quantity of sodium chlorid added to the soil, with the quantity of chlorid recovered, 

 and the total green weight of wheat obtained. Experiment 5. The left-hand column above the series 

 number represents the percentage of sodium chlorid added and the right-hand column the percentage 

 recovered from the soil. The curve at the right represents the weight (in grams) of the green wheat. 



It is clear from the results given in Table V that the absorptive power 

 of the soil for sodium chlorid is much less than for sodium carbonate. 

 An average of 85 per cent of the chlorid was recovered, and a 50 per cent 

 decrease in yield took place in the soil from which 0.16 per cent of the 

 salt was recovered. 



The results of Table V are shown graphically in figure 7. 



EFFECT OF SODIUM SULPHATE ON WHEAT SEEDLINGS 



Experiment 6.— The experiment with sodium sulphate was conducted 

 in the same manner and at the same time and with the same lot of soil 

 as experiments 2, 4, and 5. The moisture content of the soil was kept 

 at 16 per cent and the wheat was allowed to grow for 16 days. The 

 results are summarized in Table VI. 



