POTASH FERTILIZERS 



213 



vigorous plants. Like phosphoric acid and nitrogen, it 

 is utilized by crops in the early stages of growth. It does 

 not accumulate in seeds to the same extent as phosphoric 

 acid and nitrogen, but is present mainly in stems and 

 leaves ; consequently when straw crops are utilized in pro- 

 ducing manure, the potash is not lost, or as in the case of 

 nitrogen, sold from the farm. But with ordinary grain 

 farming excessive losses of potash do occur, particularly 

 when the straw is burned and the ashes are wasted. 



244. Amount of Potash removed in Crops. In grain 

 crops from 35 to 60 pounds of potash per acre are removed 

 from the soil. For grass crops more potash is required 

 than for grains, while roots and tubers require more than 

 grass. The approximate amount of potash removed in 

 various crops is given in the following table : 



POTASH PER ACRE 

 K,O 

 LBS. 



Wheat, 20 bu. 

 Straw, 2000 Ibs. 



Total 



Barley, 40 bu. 

 Straw, 3000 Ibs. 



Total 



Oats, 50 bu. 

 Straw, 3000 Ibs. 



Total 



7 

 28 



35 



8 



"38 

 10 



45 



