titles. Wood ashes, unleached, will contain from 

 4%% to 1% potash: stable manure contains about 

 OA% potash. 



The sulphate of potash is the best form in which 

 to purchase. It has no ill effects on many plants, 

 while the muriate or chloride form does. The sul- 

 phate can also be used as a "fixer" of ammonia in 

 stables and manure pits, while the muriate might 

 cause the escape of ammonia. 



AVAILABILITY. 



Buyers of fertilizers should always know the 

 source and form of the different plant foods. This 

 knowledge and the results obtained will determine 

 their availability. Nitrogen from nitrate of soda is 

 the most available form of any. Nitrogen from 

 blood is more available than that from raw bone. 



Phosphoric acid from acid phosphates (rock or 

 bone) is more soluble than the non-acid phosphates. 



Steamed bone finely ground is more soluble than 

 raw bone. The phosphoric acid from tankage is 

 more available than that from raw bone. Both the 

 nitrogen and phosphoric acid as found in animal 

 tankage and guanos, finely ground, are very avail, 

 able forms. 



Soil moisture, root acids and fermentation are 

 the dissolving agents in all soils. The high teripera- 

 tures of summer increase their action, and hence the 

 availability of fertilizing elements. 



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