CROPS AND SOIL IMPROVEMENT 



acid in the slag appears to be about as valuable 

 as each 1 per cent of the available phosphoric acid in 

 an acid phosphate. Some of the effectiveness may 

 be due to the lime, although very little of it is in 

 forms regarded as valuable for the correction of 

 soil acidity. There is evidence that basic slag 

 favors clover. It has not been found feasible to 

 ship this material many hundreds of miles inland 

 from the seaboard to compete with acid phosphate, 

 but it is an excellent source of phosphoric acid for 

 soils that are not rich in lime. 



Muriate of Potash. The mines of Stassfurt, 

 Germany, contain an inexhaustible supply of 

 potash in various compounds. Muriate of potash 

 is prepared from the crude salts, and the commercial 

 product on our markets has the appearance of a 

 coarse and discolored salt. It is handled in large 

 bags, and inclines to become moist by absorption 

 of water from the air. It contains some common 

 salt. The content of actual potash is about 50 

 per cent. The potash is readily available, but 

 the loss from leaching out of the soil is very small. 

 Muriate of potash is our cheapest source of pot- 

 ash, and should be used for all staple crops except 

 tobacco, sugar beets, and, possibly, the potato. 

 Tests even on heavy soils fail to show any injury 



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