FIELD EXPERIMENTS. 



23 



the standard fertilizers and in consequence were damaged much 

 more by the frost. In fact, the vines of the late planted potatoes 

 on the home mixed goods were practically killed at this time, 

 while the same varieties planted at the same time upon the stand- 

 ard potato fertilizer continued to grow after this frost. As a 

 result, the potatoes were larger and better ripened with these 

 than upon the home mixed plots. For quick maturing, the 

 home mixed goods apparently carried too much slowly available 

 nitrogen and too little available phosphoric acid." 



In 1905 three formulas were compared with one commercial 

 potato fertilizer. The formulas used were as follows : 



Home mixed formulas used for potatoes in ipoj. 



Ingredients. 



Number of Formula. 



3A. 



Nitrate of soda 



Screened tankage . 



Dried blood 



Acid phosphate ... 

 Sulphate of potash 



pounds. 

 100 



200 



500 

 200 



Percentage composition of fertilizer used in 1905. 



Phosphoric Acid, 



Nitrogen. 



Available. Total. 



Potash. 



Formula No. 2 



Formula No. 3 



Formula No. 3A 



Watson's Improved 



8.3 

 12.5 

 10.0 



5.0 



