36 



The Bulletin. 



*Soil better than other plats; yields too high. 



Note. — Checks for plat 8, field A, and plat 10^, field B, have been obtained from plats 

 4 and 11, and 5^ and 14^ respectively. It has been assumed that there is a uniform increase 



EFFECT OF VARYING QUANTITIES OF PHOSPHORIC ACID. 



The above experiments (in Table III) were planned to show the 

 effect on the yields of seed cotton of varying quantities of phosphoric 

 acid, the nitrogen and potash remaining the same. On one plat one- 

 half the normal quantity of phosphoric acid was applied, or an 

 amount represented by 100 pounds of 14 per cent acid phosphate and 

 equivalent to 314 per cent phosphoric acid in the fertilizer mixture. 

 On two plats were applied two and three times the normal quantities 

 of phosphoric acid, represented by 400 and 600 pounds of 14 per cent 

 acid phosphate respectively, or 56 and 84 pounds of phosphoric acid 

 per acre. The yields show good profits for all of the fertilizer mix- 

 tures, but the results are variable and do not indicate clearly what is 



