74 



kainit, on plot 6. Mr. Covington writes : ''The kainit made 

 good in every test, especially so on plots 4, 6, and 7. On 

 these plots the leaves held longer and the bolls were larger 

 and much better matured, this last being especially notice- 

 able on plot 6." 



In 1908. The field had been cleared about ten years. On 

 this land, not so deficient in vegetable matter as that used 

 the preceding year, a complete fertilizer gave the maximum 

 yield and the maximum profit. Of the three constituents of 

 the complete fertilizer, acid phosphate was most influential, 

 closely followed by both of the others. It is notable that 

 the complete fertilizer on plot 10, containing only 100 

 pounds of kainit, in addition to meal and phosphate, afford- 

 ed almost as large a yield and a greater net profit than did 

 the complete fertilizer on plot 9, which contained double 

 this amount of kainit. The net profit due to 540 pounds of 

 fertilizer on plot 10 was $14.27 (600 lbs. at 3.2 cents, less 

 |4.93) per acre. 



Apparently this soil needs a complete fertilizer and this 

 conclusion is not shaken by the slight response to acid 

 phosphate under the exceptional conditions of 1907, as 

 stated above ; this view is strengthened by the favorable re- 

 sults from complete fertilizers in earlier experiments on 

 what seem to be similar soils in that part of the state. 



Lbs. Lbs. 



1907. 190S. 



Average yield of seed cotton per acre, unfertilized 328 848 



Increase in seed cotton when cotton seed meal was added: 



To unfertilized plot 80 130 



To acid phosphate plot 194 145 



To kainit plot 219 140 



To acid phosphate and kainit plot 114 270 



Average iyicrease with cotton seed meal 152 172 



