1908.] 



PUBLIC DOCUMENT — Xo. 



123 



Indeed, at this time the 3'oung clover on all the kainite, 

 low-grade sulfate and muriate of potash plots appeared to 

 be inferior to that on the plots which had received no potash. 

 By the middle of the season there were many places in all 

 these plots on which there was no clover. Before the end 

 of the season, however, such clover plants on these plots as 

 survived became perfectly healthy, and were characterized 

 by a marked degree of vigor. It cannot be doubted, in view 

 of the unfavorable results which have been previousl}^ ob- 

 tained in our experiments where mm-iate of potash has been 

 used for clover, that it is the chlorides in the three fertilizers 

 which cause the injury. Chlorides may produce this eft'ect 

 either because of the increased loss of lime which their use 

 leads to, or possibly because of the fact that their continued 

 use brings the soil into an acid condition. Either deficienc}'- 

 of lime or presence of free acid is known to be decidedly 

 unfavorable to the growth of clover. 



All the plots in the field were cut twice subsequent to 

 June 11, viz., on August 4 and October 10. On the first 

 date there was a moderate o-rowth of small weeds and a few 

 large ones on the plots on which the clover was poor, i.e,, 

 on the kainite, muriate of potash, and low-grade sulfate of 

 potash plots. These, as far as practicable, were thrown out. 

 In estimating the significance of the difierences in yield, 

 however, it should be remembered that the real difierence in 

 the condition and growth of the clover was undoubtedly 

 greater than the figures indicate, as where the clover is 

 weakest the weeds are most numerous, and it is impossible 

 to separate them all. The crops cut were carefully cured in 

 cocks without loss of leaf, and the hay was well dried when 

 weighed. The tables show the rates of yield per acre and 

 the averages for the last two cuttings of the several potash 



salts : — 



Glover. — Yield 2)€r Acre (Pounds). 



