72 CULTIVATION AND TILLAGE 



10. What is meant by bottom water, capillary water, and hydroscopic 

 water? 



11. Which kind of water can be used by the plant? 



12. When should you practise deep and shallow plowing? 



13. Why is it necessary to vary the depth of plowing? 



14. How can we check evaporation from the soU? 



15. Discuss spring and fall plowing. 



16. What is meant by bacterial action in the soil? 



17. Name the two processes that go on in the soil that are due to bacteria. 



18. Discuss the conditions necessary for nitrification. 



