l6 AGRICULTURE FOR BEGINNERS 



3. It improves the texture of the soil. Wet soil is sticky. 

 Drainage makes this sticky soil crumble and fall apart. 



4. It prevents washing. 



5. It increases the porosity of soils and permits roots to 

 go deeper into the soil for food and moisture. 



6. It increases the warmth of the soil. 



7. It permits earlier working in spring and after rains. 



FIG. 9. LAYING A TILE DRAIN 



8. It favors the growth of germs which change the 

 unavailable nitrogen of the soil into nitrates ; that is, into 

 the form most useful to plants. 



9. It enables plants to resist drouth better because the 

 roots go into the ground deeper early in the season. 



A soil that is hard and wet will not grow good crops. 

 The nitrogen-gathering crops will store the greatest quan- 

 tity of nitrogen in the soil when the soil is open to the 



