16 VALU.K J:JF SV/AMP LANDS. 



phosphoric acid, it has little if any available potash. In this 

 same valley potatoes planted in the natural soil grow a large 

 vine and a coarse, watery tuber, unfit to eat. Add sulphate 

 of potash and the tubers grow white and "mealy", excellent 

 in quality. That is just what we would expect, knowing the 

 influence of potash on the formation of starch and on qual- 

 ity. The simple truth is that these black swamp lands are 

 really the most valuable soils on the farm. They need 

 drainage to take out the surplus water and potash to 

 provide the missing fertility. 



AVERAGE COMPOSITION OF POTASH SALTS 



and Application Recommended in Pounds per acre 



for use on Elack Unproductive Soils. 



PER CENT. 



NAME OF SALTS. OF PURE POTASH. POUNDS. 



AVERAGE. PER ACRE. 



A. Salts containing Chlorides: 



Muriate of Potash 50 200 



Manure Salt 20 600 



Kainit (crude salt) 12.4 800 



B. Salts free of Chlorides : 



Sulphate of Potash 50 200 



Sulphate of Potash-Magnesia 27 400 



