CHAPTER VI 

 MAINTAINING THE FERTILITY OF THE LAND 



107. How Soils Become Productive. It has required 

 untold ages for the soils of the world to be formed and to 

 become productive. At first the particles of rock were 

 capable of supporting only such plants as lichens and 

 mosses. After generations of these plants died and added 

 their material to the soil, it became possible for other 

 plants to grow. For thousands of years the trees and 

 leaves of the forests have fallen and decayed to form 

 the forest soils. On the great western plains where "corn 

 is king," the grasses have grown for centuries and have 

 fallen down to decay so that still larger grasses might grow. 

 When such lands are first farmed, the crops are as large 

 as the climate and culture will allow, for the soils are very 

 rich. 



108. How Rich Virgin Soils Become Less Productive. 

 The first farming of a virgin soil has nearly always been 

 grain farming. Grain is grown every year, with no pro- 

 vision for keeping up the humus supply, either by 

 means of barnyard manure or by plowing under material, 

 even the straw in the wheat-growing sections often being 

 burned. Little barnyard manure is produced, and that 

 which is formed is either thrown away or is allowed to 

 lose most of its value before being put on the land. Very 

 few farmers in any part of America have yet learned to 

 handle manure without losing one-half of its value. The 



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