148 PRACTICAL FARM CHEMISTRY. 



but also two or three times as much phosphoric acid 

 and nitrogen, as required for the crops. It will hardly 

 be good economy, therefore, to use yard manure ex- 

 clusively, especially if we should have to purchase 

 it at anything like its full value. The cheaper way 

 would be to apply a smaller quantity of yard man- 

 ure, say one-half the named quantity, or six tons, 

 every second or third year, and add to it the missing 

 sixty pounds of potash in the form of unleached 

 wood ashes, com cob ashes, cotton seed hull ashes, 

 muriate of potash, sulphate of potash, kainit, etc. 

 Tobacco refuse may also come handy as a source of 

 potash in this emergency. Tobacco dust can be 

 applied directly to the soil. Stems may be either 

 used as mulch, or composted with the yard manure. 

 My ration for the yard manure and potash salts 

 combine would be six tons of the former, and 120 

 pounds of muriate or sulphate of potash, or 500 

 pounds of kainit; and would prefer to apply this 

 every second year at least. 



We should fully understand, however, that sim- 

 ple phosphates alone are no manure for fruit crops. 

 Potash, on the other hand, is the chief 



^rruit8^°' substance needed, and we can not easily 



apply it in too large doses for fruits. A 



sufficiency of potash makes bush and tree fruits 



firmer, sweeter, better in flavor, and renders the 



wood more resistent to severe cold. 



Vegetable crops usually make still heavier drafts 

 on the potash stores of the soil than fruit crops. In 

 carrots, mangolds or turnips, for instance we remove 

 over 100 pounds of potash per acre if the crop be 

 simply a fair one, and perhaps over 200 pounds, if 

 it be a heavy one. This loss, of course, is usually 

 made up by heavy dressings of yard manure, every 



