7b 



Journal of Agricultural Research 



VcJ. XV, No. a 



FATE OF THE FERTILIZER POTASH APPLIED 



For an exact statistical allotment of the i,8oo pounds of potash 

 applied to plot 4 from r88i to 191 6, inclusive, there would be required a 

 number of data wliich tlie previously related studies have not furnished. 

 We know that there is little loss or gain of the surface soil of this plot 

 by erosive influences. The drainage is reasonably free, ♦but there is 

 no water table, for the drainage waters creep along the faces and through 

 the crevices and seams of the limestone rocks that lie only a short 

 distance beneath the surface. It has not been practicable, therefore, to 

 collect and examine the drainage water lost from these two plots so as 

 to determine the amounts of potash they severally lose through that 

 channel. The general composition of drainage waters does not suggest 

 that this loss can be large. 



We have, moreover, no entirely satisfactory notion of the potash 

 transfers from surface to- subsoil on these plots. lyittle downward 

 movement is indicated by the data at hand. 



A crude approximation of the fate of the fertilizer potash is possible, 

 nevertheless, from the data in hand if the losses by subsoil and drainage 

 are treated as relatively small, and therefore neghgible for the purpose 

 of the computation. 



The total yields (in pounds) to the acre, 1881-1916, for the respective 

 rotation crops were, according to data supplied by Prof. C. F. Noll, of 

 the Department of Agronomy of this Station : 



If we estimate the potash removed by unit weights harvested of these 

 several kinds of crops to have been, on the average, equal to the cor- 

 responding removals during the rotation 1910-1913, the total quantities 

 thus taken from the two plots were : 



