314 



EXPERIMENT STATION RECORD. 



and among these is the presence of much or little water in the soil. 

 The influence of water has of late been much studied, and in some 

 cases has been found to exceed that of .soil, fertilizer, and thickness 

 of .seeding". 



The life-giving influence of water in the plant world is well known. 

 The enormous irrigation enterprises in the warmer regions carry fer- 

 tility everywhere, and especially where the soil is naturally rich. The 

 work of Hellriegel ' is of especial value in studying the importance of 

 this factor in plant production. Fittbogen^ has also made a careful 

 study of this subject, and more recently A. Mayer, Pagnoul, Remy, 

 and especially von Seelhorst^ at Gottingen. The latter, with Tucker 

 and Wilms,* has made a study of the influence of much and little water 

 in the soil upon the taking up of fertilizing ingredients and the com- 

 position of the ash. In general it was shown that when an insufficient 

 amount or " little water " was provided the crops of potatoes, oats, 

 grass, and clover were diminished, and that the 3'ield was materially 

 increased by a medium amount or still more by " much water.'' In the 

 increased crops grown with much water the percentage of ash in the 

 dry substance was not lessened as compared with that of the crop 

 grown with little water, but, on the contrary, was often somewhat 

 greater, as in the case of the potato; hence it would appear that when 

 plentv of water is present in the soil much more of the ash constituents 

 are taken out b}^ the plant than when there is a deficiency of water. 



The percentages of potash, lime, phosphoric acid, sulphuric acid, and 

 chlorin fluctuate with the changes in the amount of water pre.sent. 

 This is shown in the case of potato tubers,' for example, as follows: 



Ash of potato tubers grown ivith much and little water. 



There was an increase in the percentages of lime and of chlorin with 

 the use of much water, while the potash decreased somewhat. 



^ Beitnige zu den naturwissenschaftlichen Grundlagen des Ackerbans mit beson- 

 deren Beriicksichtigung, u. s. w. Braunscweig, 1883; Jour. Landw., 31 (1883), p. 376. 

 ^Laiidw. Jahrb., 2 (1873), p. 353. 

 *Jour. Landw., 47 (1899), p. 369. 

 *Ibid., p. 251. 

 = Daszewski and Tollens, Jour. Landw., 48 (1900), p. 223. 



