19 



"The requirement of plants for nutrition as I have emphasized 

 already in previous publications is by no means identical with 

 the requirement by way of fertilization. On the contrary, a 

 plant with a great demand has often a correspondingly greater 

 capacity to satisfy that demand than another plant which is 

 satisfied with much less, and does not require a correspondingly 

 great supply of easily assimilable nutriment as that other. A 

 relatively greater demand, as we perceive everywhere in 

 nature, is generally accompanied by a correspondingly greater 

 capacity for the satisfaction of that demand. Lucerne, for 

 instance, requires nearly four times as much nitrogen as wheat, 

 but for that reason the lucerne is equipped with the ability to 

 utilize a much richer source of nitrogen (the atmosphere) than 

 the wheat, which is compelled to rely for its nitrogen supply 

 upon the soil. And so it is with the potash (kali) question. 

 The capacity to take up the potash (kali) supply of the soil 

 and to utilize the potash (kali) so taken up differs amongst the 

 various plants." 



" For several years, and particularly during the past summer, 

 I have carried out a series of potash (kali) fertilization experi- 

 ments in order to make this matter clear. 



"In March experiments were started with summer cereals 

 (wheat, rye, oats and barley), peas, potatoes, red clover, sugar- 

 beets, vetches, lupines, summer rape, beets, partly in vegetation 

 vessels, partly on the field, for the purpose of answeiing the 

 following questions: 



1. \Vhat is the potash (kali) requirement of the various 

 plants ? 



2. To what extent can the various plants stand potash (kali) 

 fertilization ? 



3. How does potash (kali) fertilization affect the quality of 

 the crop?" 



" Of several pot experiments photographs were taken on June 

 5th, and June nth, and I have added these to the publication. 

 " The photographs represent: 



1 . Experiments with barley, potatoes and peas in larger ves- 

 sels, holding 1 8 kilo earth (about 40 Ibs. [39.6] ). 



2. Experiments which were made with peas, wheat, rye, 

 oats and barley in smaller vessels, containing 6 kilo earth 

 (i3^tbs. [13-22] ). (See illustrations.) 



