55 



kaiuit. The poor results on plots 1 and 2 and 5 appear +0 be 

 parti}' due to the slightly poorer stand on those plots. 



In 1908 a complete fertilizer was the most profitable; in 

 this potash was most important, nitrogen next. Acid phos- 

 phate was ineffective when used alone or with meal, but 

 profitable when combined with, both kainit and meal, mak- 

 ing a complete fertilizer. 



In the 3 tests on this typical prairie soil, the most profi- 

 table fertilizer was in two cases a complete fertilizer and in 

 one case kainit. 



190^ 1907 19i)^ 



lbs Lb-. L!)s. 



•Average yield of seed cotton per acre, unfertilized .380 365 431 

 Increase of seed cotton when cotton seed meal was added: 



To unfertilized plot 120 78 145 



To acid phosphate plot — 127 66 149 



To kainit plot — 37 gg 127 



To acid phosphate and kainit plot 42 — 30 187 



Average increase with cotton seed meal — 1 12 152. 



Increase of seed cotton per acre when acid phosphate was added : 



To unfertilized plot 276 — 14 15 



To cotton seed meal plot 29 120 — 11 



To kainit plot 85 73 84 



To cotton seed meal and kainit plot 164 — 46 144. 



Average increase tvith acid phosphate 130 33 50^ 



Increase of seed cotton per acre when kainit was added : 



To unfertilized plot 183 233 113 



To cotton seed meal plot 26 400 101 



To acid phosphate plot — 8 320 218 



To cotton seed meal and acid phosphate plot 161 234 356 



Average increase ivith kainit 91 297 199 



