1 88 



SOILS 



cially valuable. Its power to go deep opens new pastures 

 to plant roots. The closely packed soil, untouched by 

 other plows, is made fertile and friable. The subsoil plow 

 brings this new zone, with its accumulated reserve of 

 plant nutrients, within reach of the plants. It almost adds 

 a new farm to the old one. 



Subsoiling is an expensive process, yet in no other way 

 can the hard floor under the top soil a floor that plant 



PLOWING LEVEES FOR RICE 



roots vainly seek to penetrate ; a floor that turns the rain 

 above it, and imprisons the food beneath it in no other 

 way can this floor be broken through. In no other way 

 can the sun, air, and moisture be admitted to the depths 

 below, where they are needed to fit the soil for an ideal 

 plant home. In no other way can undissolved plant food, 

 held fast in the dark compounds below, be liberated. 



