126 



FERTILIZERS 



comes humus, and makes the soil looser in texture, more 

 able to hold moisture, and better able to turn its plant 

 food into available forms. 



Manure is also highly useful as a direct fertilizer. Its 

 composition varies with the animals, their bedding, and 

 with the kind of food they have had. A ton of average 

 barnyard manure supplies from 10 to 15 pounds of nitro- 

 gen, from 4 to 9 pounds 

 of phosphoric acid, and 

 from 9 to 18 pounds of 

 potash. Thus, though 

 low in its proportion of 

 phosphorus, it contains 

 all the substances that 

 soils are most likely to 

 lack. It is a " complete 

 fertilizer." 



Fresh manure, how- 

 ever, decomposes rap- 

 idly if exposed to the 

 air, and so loses much 

 of its value. The care 

 and use of it, therefore, 

 are of vital concern. 

 The nitrogen and the 

 potash are the elements 



most likely to be lost. The best way to prevent this loss 

 is to spread the manure on the land as soon as possible. 

 The three direct fertilizing elements are found mainly in the 

 liquid manure. Care should be taken to provide bedding 

 enough to absorb and hold this, and in this way to apply 

 it directly to the soil. The farmer should see that it is 

 not allowed to drain off into a passing stream. 



84. Green Manure. Green clover, cowpeas, and rye are 



A LIME KILN. 



