VALUE OF FERTILIZERS. 331 



same land without manure of any kind, would not the soil become 

 equally poor in potash ? " 



" No," said I, " because you would, in such a case, get very 

 small crops small, not from lack of potash, but from lack of nitro- 

 gen. If I had land which had grown corn, potatoes, wheat, oats, 

 and hay, for many years without manure, or an occasional dress- 

 ing of our common barnyard-manure, and wanted it to produce a 

 good crop of potatoes, I should net expect to get it by simply 

 applying potash. The soil might be poor in potash, but it is 

 almost certain to be still poorer in nitrogen and phosphoric acid. 



Land that has been manured with farm yard or stable manure 

 for years, no matter how it has been cropped, is not likely to need 

 potash. The manure is richer in potash than in nitrogen and 

 phosphoric acid. And the same may be said of the soil. 



If a farmer uses nitrogenous and phosphatic manures on his 

 clayey or loamy land that is usually relatively rich in potash, and 

 will apply his common manure to the sandy parts of the farm^ tie 

 will rarely need to purchase manures containing potash. 



