1903.] 



PUBLIC DOCUMENT — Xo. 38. 



123 



Indeed, at this time the young eh)vcr on all the kainite, 

 low-grade sulfate and muriate of potash plots {tppeared to 

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

 By the middle of the season there were man\' places, in all 

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

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

 survived became perfectl}^ healthy, and Avere characterized 

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

 of the unfavorable results which have been previously 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 injur3^ Chlorides may produce this eftcct 

 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 deficiency 

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

 unfavorable to the growth of clover. 



All the plots in the field Avere cut twice subsequent to 

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

 date there was a moderate growth 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 loAV-grade sulfate of 

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

 In estimating the significance of the difl^erences in yield, 

 hoAvever, it should be remembered that the real difference in 

 the condition and groAvth of the clover AA^as undoubtedly 

 greater than the figures indicate, as Avhere the clover is 

 weakest the weeds are most numerous, and it is impossible 

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

 cocks Avithout loss of leaf, and the hay Avas well dried Avhen 

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

 the averages for the last tAvo cuttings of the several potash 



salts : — 



Clover. — Yield 2^67' Acre (Pounds) . 



Potash Salt. 



Hay. 



First Cut, 

 Rowen. 



Second 



Cut, 

 Rowen. 



Total 



No potash, 

 Kainite, . 

 High-grade sulfate. 



2,458 

 2,681 

 2,681 



2,078 

 2,491 

 2,301 



1,273 



1,475 

 1,564 



5,809 

 G,647 

 6,546 



