Fish Guano 



I. Fish guano. 2. Fish manure. 3. Fish 

 powder. 



It constitutes what is known as a complete 



manure, containing nitrogen, phosphoric acid, and 



potash, though the latter is only in small quantities. 



The guano is obtained by drying the fish and 



after\vards reducing it to powder. 



Fish manure varies in quality and composition, 

 according to the material from which it is obtained, 

 the method of preparation, and the impurities found 

 in it. If made from salt fish, it contains a great 

 deal of salt, which, not being manure and taking the 

 place of that which is, lessens its value. If the fish 

 waste includes the livers, which are oily, the value 

 of the manure is again diminished, because the con- 

 servmg qualities of the oil hinder the decomposition 

 of the organic matter and retards its assimilation. 



Herring Guano, still called Guano Powder, is 

 oily throughout, and of inferior quality to that 

 obtained from non-oily fish, known as White Fish 

 Guano. However, the oil, having no value from 

 the agricultural point of view, makes the manure 

 poorer than its drawbacks warrant, for it must be 

 present in considerable quantities to retard the 

 decomposition of organic matter for any appreciable 

 time; 3 or 4 per cent, is not harmful from this 

 point of view. 



Guano made of waste, especially if it is made of 

 bones, can contain great quantities of phosphates j 

 sometimes, if it is made exclusively of bones, repre- 

 senting as much as 50 per cent, phosphate, and 

 about 4 per cent, nitrogen. 



When the waste consists more especially of the 



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