166 
ELEMENTARY AGRICULTURE 
phosphate, and six or eight per cent of potash. Such a 
fertilizer will add much to the yield on many of our soils. 
Commercial fertilizers are applied most often at the 
time of planting the crop. Attachments have been de¬ 
vised for applying the desired number of pounds per 
acre, as the drill or planter drops the seed. If sufficient 
manure and green materials have already been plowed 
under, a light application of commercial fertilizer will 
prove beneficial. 
QUESTIONS 
1. What is tillage? 
2. Give several reasons why we till soil. 
3. State the advantages of fall plowing. 
4. Tell how to subsoil land. 
5. What is the function of the harrow? 
6. Give three ways of mulching soil. 
7. Mention four ways of supplying organic matter to soil. 
8. How is good drainage established? 
9. Name three kinds of drainage and state the best kind for the 
South. 
10. What is terracing? 
11. What are natural, green, and commercial fertilizers. 
12. How are terraces laid out? 
13. Name several forms of commercial fertilizers. 
14. Give the time and method of applying commercial fer¬ 
tilizers to the soil. 
15. What are the three big problems to be considered in im¬ 
proving farm land? 
PRACTICAL WORK 
Exercise 1 
Object: To learn the methods of handling soils. 
Procedure: As a home project, try plowing a small plot in the 
fall and compare it with that plowed in the spring. 
Observe a crop of rye shown in the fall and plowed under in the 
spring. A crop of peas may , also serve as a green manure crop. 
