CHAPTER XII 



FERTILIZATION AND FERTILIZERS 



WHEN all the various operations and precautions 

 described above fail to give good crops, we must con- 

 clude that food substances are lacking in the soil, and 

 that we must supply these by putting them on the land. 

 Sometimes even fresh soils. (" poor lands ") do not 

 naturally contain enough plant food to supply more 

 than one or two crops. 



Farmyard manure. The fertilizer which has been 

 used longest and is justly very highly prized is stable 

 or farmyard manure, the offal from farm animals, mixed 

 with straw or other litter with which these animals 

 have been bedded. This manure, of course, contains 

 all that the food of the cattle has taken from the land, 

 less what has been used for the growth and products 

 (milk, eggs, etc.) of the animals themselves. By putting 

 the barnyard manure back on the land (which should 

 always be done), we return to the soil a very large part 

 of what was taken from it by the crops. But, of course, 

 a part so much as has been sold from the farm - 

 is not returned. So even if we put back all the stable 

 manure, there will be a lack or deficit in the return, 

 which will have to be made up some time. 



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