Worn-Out 

 Land. 



How to Restore 

 and Maintain 

 Fertility. 



Causes of 

 Worn-Out 

 Land. 



Application of 



Vegetable 



Matter. 



Advantages of 

 Humus. 



Humus All 

 Important. 



CHAPTER VII. 

 Cultivation of the Soil. 



Many farms in the older sections of the country 

 have become exhausted by too deep plowing, which 

 has buried the vegetable matter with the crude 

 subsoil, and thus made it unavailable for plant food. 

 This practice is contrary to the laws of nature. 



In our new and fertile lands we find the vegetable 

 matter on the surface — where it properly belongs. 

 By shallow plowing, thorough cultivation, and a 

 systematic rotation of crops, the fertility of the soil 

 can be maintained indefinitely. 



Worn-out land is really land on which the 

 vegetable matter (humus) has been buried, or de- 

 stroyed by continuous cropping with grain. 



Such land can be renewed only by applying 

 vegetable matter on the surface and incorporating 

 it with the surface soil so that it will decompose and 

 form what is termed humus. 



Humus has a distinct value apart from the plant 

 food it contains. It absorbs and retains moisture 

 much more readily than any other soil ingredient, 

 so that a soil rich in humus will withstand drought 

 without drying out and becoming hard. 



Humus aids in the decomposition of mineral 

 matter in the soil. It also fixes ammonia of animal 

 matter and thus prevents it from being lost by 

 leaching or evaporation. It improves the texture 

 and mechanical condition of a heavy soil, making it 

 lighter, more porous and less adhesive or sticky. On 

 a sandy soil, humus serves to bind together the loose 

 particles of sand and so prevents the soil from drift- 

 ing, and arrests the excessive leaching of plant food. 



