Potassic Manures in General 



but the moment there is sufficient lime in the ground 

 no further loss of potash will take place. 



Sandy soils with little or no humus are equally 

 unable to hold their potassic salts. But here it is 

 not sufficient only to apply lime, because there is 

 not enough humus to retain the potash, or to 

 prevent loss. It will be wiser in this kind of land 

 to use only a little potassic manure at a time — just 

 what is necessary for the crop, and not to apply it 

 a long time in advance. For if in the generality of 

 cases there is little or no loss of potash, in the two 

 cited the total loss will be very serious, that is if 

 there is an insufficiency of humus and lime. 



Forms in which Potash is found. 



Potash is usually restored to the soil in one of the 

 three following forms : 



ist. In the form of farmyard manure or seaweed. 



2nd. In the form of ash. 



3rd. In the form of chemical manure. 



Actually we have a great variety of potassic 

 manures, the source of the majority, however, being 

 the mines at Stassfurt in Germany ; and for many 

 years past Leopold's Hall has been the station 

 whence an enormous bulk of potassic products has 

 streamed out in all directions all over the world. 

 The exploitation of these potassic salts began in 

 i860 and developed to such an extent that in 1906 

 about 5,200,000 tons, or 1700 waggons of 10 tons, 

 were exported every working day. In 1905 2,500,000 

 tons of kainite alone were sold, yet the Stassfurt 

 mines still contain imcalculated reserves. They 

 are derived from the evaporation of sea water in a 



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