238 Report on 'Crop Production of the 



Pagnoul^^ decided that a plant may take up soda, yet in plants 

 grown with soda, the potash content was three times as large as 

 that of soda. Plants which received only potash contained no 

 soda or at least not more than traces. Oats, he stated, will not 

 take up soda as long as there is potash present, yet in case of a 

 shortage of salts of the latter, soda may have a beneficial action. 

 Paul Wagner^o concluded from experimental work that soda 

 may have an essential influence upon the development of the 

 plant, and that the crop may be increased almost one-half by 

 using salt with a potash fertilizer; but it is impossible for soda 

 to perform all the functions of potash in plant growth. 



Maercker^t^ gave results showing the beneficial action of 

 sodium and magnesium chloride when applied with potash in 

 the Stassford salts. 



The author's (Stahl-Schroeder) own work was planned first 

 to gain some light on the question of the presence of soda in 

 plants and second to determine the possibility of partially replac- 

 ing potash by soda in plants. 



Working with the oat plant he found soda present in prac- 

 tically all cases even with a large supply of potash in the fer- 

 tilizer. This was true of roots, straw and grain. 



To solve the second question the author resorted to pot experi- 

 ments growing peas, oats, carrots and buckwheat in Wagner's 

 vegetation pots, using a potash-poor peat soil. All the pots 

 received phosphoric acid, lime, nitrogen and magnesia. In addi- 

 tion two pots in each set received two grams potash and two 

 two grams soda. The increase of the weight of the crop was in 

 all cases so small, when using soda, over the pot receiving 

 neither potash nor soda that the action, either direct or indirect, 

 of the soda is certainly not worth considering. 



Chemical analysis of the crops receiving neither potash nor 

 soda showed a low percentage of potash and as a rule a larger 

 percentage of soda. With the pots receiving potash this was 



^^Biedermann's CentralbJatt, 1895. 



""Die Stickstoffdungung der landw. KulturpAanzen. Berlin : 1892. 



*^ Arheiten der dcvtschen Landwirtschafts-Gesellschaft, 20. 



