EFFECT OF POTASH SALTS ON CROP YIELDS 



4.5 



Effect of Use of Fertilizer Potash 



Actual measurement of crop response to fertilizer potash is also made 

 on Field G. This is tiie best laid out of tiie older field experiments of 

 tiie Station, witli plots one-fortietii of an acre in area and treatments 

 replicated five times. Tiie ])]an of a single series out of the five, precisely 

 similar to tiie other series, is siiown in tlte diagram given below. In 

 addition to potash sources listed, an eiglitli jilot received at different times 

 silicate of potash, feldspar and Security Potash Treater Dust. Because 

 of this varied treatment, results from this last plot are not presented in 

 tins report. , 



The annual fertilizer treatment was as follows: 



Nitrate of soda, 250 pounds per acre 

 Tankage, 270 pounds per acre 



Acid phosphate, 360 pounds per acre 



In addition, i;J5 pounds per acre of potash (K20) were applied 

 annually in six different carriers, up to and including 1916, this amount 

 being reduced in 1917 and succeeding years to 81 pounds per acre. All 

 the fertilizer was spread in a single annual application, usually broadcast 



