Lime 



the only one — which can really impoverish the soil. 

 For nitrate, as we saw, does not impoverish. 



The most favourable time to apply lime is 

 between the dressings of farmyard manure. By 

 using the right quantity of lime the formation of 

 ammonia will be promoted, and also that of nitrate 

 from the massimilable nitrogenous organic matters 

 in the soil, and so economical crops can be 

 obtained. 



In order that carbonated lime or plain limestone 

 can be effective in acid ground they must first be 

 treated with the acids of the soil. The finer the 

 limestone the more easily will it be affected, but the 

 effect will also be in direct relatign to the strength 

 of the acids. In any case the action of limestone 

 will be slow, less energetic, and less complete than 

 that of quicklime, and some acids — such as carbonic 

 acid and tannic acid — will have no action upon it 

 whatever. Therefore, carbonate (of lime) is not 

 sufficient to neutralise these acid soils, whereas 

 quicklime acts rapidly and efficiently in the forma- 

 tion of the humates, which play such an important 

 part in retaining the ammonia and other fertilising 

 matters. Besides the carbonate formed from lime 

 will be found in the soil in a much finer form than 

 can be obtained by ground limestone, etc., and then 

 will have more effect than ordinary limestone. 



Large applications of lime are generally to be 

 condemned. First on account of the outlay they 

 represent. Afterwards, the lime, acting energetically 

 on the organic matters and mineral constituents of 

 the soil, makes them very assimilable to plants which 

 at the outset will produce a luxuriant vegetation, 



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