220 Chlorine and Plant Growth [418 



crease followed where NaCl was superimposed upon the usual 

 complete ration. 



For the greenhouse cultures in Miami silt loam, fifteen or 

 twenty kilograms of air-dry soil were employed, in cypress 

 boxes, the salts being added as in the case of the sand cul- 

 tures. The total application of salts approximated from 0.06 

 to 0.15 per cent, of the dry weight of the soil. 



The sugar beet produced 50 per cent, more dry substance 

 (root) when chlorine was included with the usual salt ration 

 than when the ration without chlorine was used. The 

 glucose content of the root was increased somewhat, percen- 

 tagely on the basis of dry weight, but the sucrose content was 

 uninfluenced by this treatment. Preliminary experiments 

 with the radish indicate that it is little affected by the chlorine 

 supply, while the growth of the carrot is stimulated and that 

 of the parsnip is depressed as regards content of dry matter 

 and percentage of sugars. Similar experiments with the po- 

 tato (" Triumph " and " Eural New Yorker " varieties) gave 

 the same dry weights of tubers, whether potassium was sup- 

 plied as the chloride or as the sulphate. 



In the field experiments, sugar beet roots showed an increase 

 of from 10 to 30 per cent., by weight, where NaCl was ap- 

 plied to the soil at the rate of from 260 to 520 pounds per 

 acre, as compared with those of the unfertilized plot. The 

 glucose content was increased, but that of sucrose was unaf- 

 fected by this treatment.' 



The potato (" Triumph " variety) produced the same yield, 

 both of total and marketable tubers, whether supplied with 

 potassium as KC1 or as K 2 S0 4 , in the complete fertilizer 

 ration. The addition of NaCl without other salts depressed 

 the yield. Another experiment with potato ("Eural New 

 Yorker" variety) showed that the starch content and cook- 

 ing qualities of the tuber were the same whether potassium 

 was supplied as KC1 or as K 2 S0 4 , in the complete fertilizer. 

 Fertilization with NaCl alone gave tubers of lower starch 

 content and poor quality. It thus appears that the depress- 



