42 



Journal of Agricultural Research 



ACTION OF THE VARIOUS IONS 



COMPARISONS OF CATIONS AND ANIONS 



In order to determine the effect of the different ions and to compare 

 the relative action of the cations and anions, the results of the various 

 tests were summarized and are presented in Tables XIII and XIV. 

 These data represent the averages of the various concentrations of the 

 salts in three different soils; hence, they should be fairly reliable. 



On examining Table XIII it will be seen that the chlorid was by far 

 the most toxic anion, followed by the nitrate, carbonate, and sulphate 

 in the order named. This order held for all salts regardless of the basic 

 ion, and is contrary to ideas on the subject previously held, as the 

 carbonate was thought by many writers to be most injurious. 



Table XIII. 



-Effect of various anions on the germination and growth of wheat. Aver- 

 age for J soils and lo concentrations for each soil 



In Table XIV a comparison is made of the various cations. Sodium is 

 seen to be most injurious of all the bases except ammonium. Sodium 

 is followed by calcium, potassium, and magnesium in the order named. 

 This same order of toxicity held with all the acid radicals that were tried. 



