418 Report of the Department of Field Crops of the 



A detailed statement may be found in that bulletin of the rea- 

 sons for taking up that line of work, the conditions involved and 

 the arrangement of the experiments as planned and executed in 

 1897. The situation, briefly summarized, was as follows: 



(1) Farmers on Long Island were found to be quite generally 

 using 2,000 pounds of high grade commercial fertilizers per acre 

 in growing potatoes, an amount largely in excess of the needs of a 

 single crop. 



(2) Experiments for two years by Dr. Van Slyke indicated that 

 1,000 pounds per acre was the maximum profitable quantity, but 

 his experiments did not show what would follow during a series 

 of years. 



(3) A general opinion appeared to prevail that the sulphate of 

 potash was preferable to the muriate in potato growing chiefly on 

 account of the effect of the latter on the quality of the product. 



(4) A fertilizer formula based on the composition of the crop 

 is urged by some. On the other hand the farmers of Long Island 

 had very generally come to adopt what is known as the 4, 8 and 

 10 formula, the economy of which seemed to have no general sup- 

 port except the somewhat inconclusive approval of common prac- 

 tice. 



The experiments as conducted in 1897 were planned, therefore, 

 with reference to answering the following questions : 



(1) What is the profitable quantity of commercial fertilizer to 

 use in growing potatoes on Long Island? 



(2) Is the 4, 8 and 10 formula better than one which recognizes 

 only the composition of the crop? 



(3) Is the sulphate of potash better than the muriate for potato 

 growing, quantity 'and quality both considered? 



The results for a single season (1897) taken by themselves 

 without reference to the influence of continued practice gave the 

 following indications, viz. : 



(1) That more than 1,000 pounds of fertilizer was used at a 

 loss. 



