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The Bulletin. 



Table II— 

 AVERAGE RESULTS FOR SEVEN 



Note. — Checks for plats 8, 9 and 10, Field A, and plats 102, II2, 122 and 132, Field B, have 

 been obtained from plats 4 and 11 and 52 and 142 respectively. It has been assumed that 



EFFECT OF VARYING QUANTITIES OF NITROGEN. 



These tests (Table II) were planned to determine the effect on the 

 yield of cotton of varying quantities of nitrogen, leaving the phos- 

 phoric acid and potash constant. On one plat the nitrogen was re- 

 duced to one-half of the normal quantity, making the application 5 

 pounds of nitrogen per acre or practically II4 per cent in the ferti- 

 lizer mixture. On two of the plats it was increased by 2 and 3 times 

 the normal quantity (10 pounds per acre), making the application 

 20 and 30 pounds per acre respectively, or on basis of the fertilizer 

 mixture 5 and 71^ per cent. The average results for four years on 

 plats in Field A show the largest yield and profit from the fertilizer 

 application containing one-half the normal or the smallest quantity of 

 nitrogen in the several mixtures. In two years' and one year's test 



