Potassic Manures in General 



French Midi, whence it can be brought via Marseilles, 

 the salins of beetroot, etc., can be exploited, and 

 above all by constructing tanks for urme, covering 

 our farmyard manure, and so checking loss, we can 

 reduce the necessity of looking abroad for our potash 

 to a minimum. 



The necessity for supplying potash to the soil has 

 been questioned, and occasionally even doubted. 

 Such discussions serve no purpose. Many soils are 

 in real need of it, and most are better for it, but in 

 some cases the ground already contains sufficient. 



Manurial Attributes of Potash. 



Still, a distinction must be observed with regard 

 to the nature of the crops on which it is tried, one 

 kind being able to assimilate the potassic com- 

 binations in the soil more easily than another. 

 Furthermore, in some cases the simultaneous use of 

 other manures or substances acting as lime does 

 has caused the immediate utilisation of the potash 

 present. 



Potash is one of the principle elements — some- 

 times nearly predominant — in the ash of plants, and 

 it must be restored to maintain the fertility of the 

 soil ; only in its application certain points must be 

 observed. 



Commercial potassic manures are more or less 

 corrosive in themselves. Moreover, they are fre- 

 quently mixed with magnesium salts which are 

 actively injurious to the roots of vegetating plants. 

 That is why these compounds are generally applied 

 before sowing, and sometimes a long while in 

 advance and on fallow, so that the rams can wash 



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