WHEAT. 



183 



phoric acid, removed in the grain, in the straw, and in the 

 total produce (grain and straw together) of plots 11, 12, 13, 

 and 14, above referred to, during each of the four 10-yearly 

 periods of the 40. 



TABLE 52. — Potash, Soda, and Phosphoric Acid, per acre per 

 annum, in Grain, in Straw, and in Total Produce, op 

 Wheat. Forty years, 1852-91. 



Plot 11. Ammonium-salts=S6 lb. nitrogen, and superphosphate. 



Plot 12. Ammonium-salts = 86 lb. nitrogen, superphosphate, and soda (potash previous to 



1S52). 

 Plot 13. Ammonium-salts =86 lb. nitrogen, superphosphate, and potash (potash previous 



to 1852). 

 Plot 14. Ammonium-salts = 86 lb. nitrogen, superphosphate, and magnesia (potash previous 



to 1852). 



As the description above the table shows, each of the four Details of 

 plots, 11, 12, 13, and 14, received annually during the 40 Jjgf 

 years, 1852-91 inclusive, ammonium-salts = 86 lb. nitrogen 

 per acre, and also superphosphate each year. Plot 11 re- 

 ceived no potash during the 40 years, nor any during the 8 

 preceding years of the experiments. Plot 12 received no 

 potash during the 40 years, but a soda-salt instead ; it had, 

 however, received 587 lb. of potash per acre during the 8 pre- 

 ceding years. Plot 13 received a liberal supply of potash in 

 each year of the 40, and it had received 737 lb. during the 

 preceding 8 years. Lastly, plot 14 received no potash during 



