84. 



AGRICULTURE 



unless they have food, warmth, air, and moisture, and are protected 

 from strong light. In poorly- drained soils, there thrive harmful 

 bacteria which consume nitrogen and make the soil acid and unfit 

 for plant life. 



Common sense and it is nowhere more important to listen 

 to its voice than on the farm will tell you that as soils differ in 

 character, they need different treatment. Each kind has its special 

 natural defects and adaptations, of which you have already learned 

 something. 



Clay Loam Sand 



THE TEXTURE AND RELATIVE SIZES OF SOIL GRAINS 



Improving Sandy Soils. On account of the size of its particles, 

 a coarse, sandy soil has little power to hold moisture and plant food. 

 Elements needed by plants are often dissolved by rain water and 

 leached or washed out. In dry weather, its crops suffer for moisture. 



What can a farmer do to improve a sandy soil ? If it be not too dry 

 and coarse, he can make it very productive, for it responds quickly 

 to good tillage and fertilizing. It needs to be kept compact by 

 rolling and other methods of cultivation. It needs to have its 

 soil spaces filled with humus so as to enable it to hold food and 

 moisture: this is best done by applying green manures and well- 

 rotted stable manure. It needs to have its losses of plant food 

 supplied by application of manures and commercial fertilizers. 



Improving Clay Soils. In a clay soil the texture is often too 

 close. Water runs off its surface, and plant food and moisture are. 



