30 



Increase of seed cotton per acre when kainit was added: 



To unfertilized plot 129 lbs. 187 lbs. 37 lbs. 



To cotton seed meal plot 193 lbs. 329 lbs. 110 lbs. 



To acid phosphate plot 95 lbs. 300 lbs. 91 lbs. 



To cotton seed meal and acid phos. plot 149 lbs. 66 lbs. — 9 Ibs- 



Average increase with kainit 141 lbs. 221 lbs. 57 lbs. 



-Experiments Made by W. F. Fulton, one Mile South of 



COLLLINSVILLE_, DeKaLB CoUNTY. 



Soil reddish or mullatto, suhsoil i-ed. 



For table showing yields see page 31. 



Both in 1902 and in 1903 the largest increase resulted 

 from the use of cotton seed meal and acid phosphate to- 

 gether. Plainly kainit was not needed. Neither was cotton 

 seed meal alone, nor phosphate alone, sufficient. This is 

 the fifth fertilizer experiment with cotton that Mr. Fulton 

 has made on the red soils of Big Wills Valley, the first at 

 Larimore and the later tests at Collinsville. Each year 

 the description of the soil is about the same, reddish valley 

 soil, underlaid by red clay, and all apparently calcareous. 

 *rhese tests all agree in showing: 



(1) That the chief need of cotton on this soil is for phos- 

 phate. 



(2) That the addition of cotton seed meal to the acid 

 phosphate is profitable. 



(3) That in the presence of phosphate and meal kainit 

 is useless. 



The results suggest that the best fertilizer for these val- 

 ley soils is one containing more phosphate than meal. I 

 suggest 200 pounds acid phosphate and 100 pounds cotton 

 seed meal. Earlier results are recorded in bulletins 102, 107 

 and 113 of this station. The following analysis shows the 

 increase attributed to fertilizers in 1902 and 1903 : 



