New York Agricultural Experiment Station. 115 



Amount of Phosphoric Acid Applied and Removed. 



Summarizing this table, we can make the following state- 

 ments : 



(1) When no fertilizer was applied, the crop removed from the 

 soil 15 pounds of phosphoric acid the first year and 11.4 pounds 

 the second year, or a total of 26.4 pounds for the two years. 

 Under the conditions present, this total represents the amount 

 of phosphoric acid available for the potato crops at the time and 

 under the prevailing conditions: 



(2) When an application was made in 1895 of 1,000 pounds of 

 fertilizer, an average amount of 76.9 pounds of available phos- 

 phoric acid was supplied per acre. In 1895 the crop used 19.2 

 pounds of phosphoric acid and in 1896 14.8 pounds, making a 

 total of 34 pounds an acre for the two years. 



(3) When an application was made in 1895 of 2,000 pounds of 

 fertilizer, an average amount of 160.2 pounds of available phos- 

 phoric acid was supplied per acre. The first year the crop re- 

 moved 19.5 pounds an acre, and the second year 16 pounds; and, 

 during the two years, 35.5 pounds. 



(4) When 76.9 pounds of available phosphoric acid were added 

 to the soil, the crop used only 34 pounds, or less than half the 

 amount added, and only 7.6 pounds more than the amount used 

 by the crop grown on unfertilized soil. 



(5) When the amount of phosphoric acid applied was increased 

 to 160 pounds an acre the crop used only 35.5 pounds, less than 



