75 



Increase in seed cotton per acre when kainit was added: 



To unfertilized plot 215 lbs. 



To cotto-nseed meal plot 302 " 



To acid phosphate plot 205 " 



To cottoDjseed meal and acid pho.s. plot. . . .270 



?f 



Average increase with kainit 24:8 ** ■ 



The lessons taught by this experiment are plain. The 

 soil was deficient in nitrogen, phosphoric acid and potash. 

 Every fertilizer was unprofitable when applied separately. 

 Every combination of two fertilizers was but slightly pro- 

 fitable; all three used together were necessary for most 

 profitable results. The complete fertilizer containing 200 

 pounds per acre of kainit (plot 9) was more profitable than 

 the one containing half that quantity (plot 10). While cot- 

 tonseed meal, acid phosphate and kainit were all necessary, 

 the latter exerted the greatest influence in augmenting the 

 yield during the unfavorable season of 1897. 



The experimenter reports that rust prevailed on all plots 

 without kainit, and that it was most destructive on the un- 

 fertilized plots. 



It is evident from the data given elsewhere in this bulle- 

 tin, that the favorable effect of kainit was at least largely 

 attributable to its rust-restraining tendency. 



Doubtless on any other field than that growing a pea crop 

 the preceding year, cottonseed meal would have afforded 

 a larger increase in yield. 



GROUP in. NITROGEN MOST EFFECTIVE. 



Experiment Made by J. L. Ballakd for Southwest Alabama 

 Agricultural School. .Jackson, Clarke County. 



Red soil, 5 inches deep ; subsoil red clay. 

 This upland field had been cleared ten years, the original 

 growth having been pine, oak, etc. It was in corn and cow- 

 peas in 1896, in cotton in 1894 and 1895. The weather was 



