REVIEW QUESTIONS 



CHAPTER I 



i. From what are soils derived ? 2. What are the physical prop- 

 erties of soils ? When do soils differ physically, when chemically ? 

 3. Why do soils differ in weight ? Arrange clay, sand, loam, and 

 peat in order of weight per cubic foot. 4. When wet, what would 

 be the order ? 5 . What is the absolute and what the apparent 

 specific gravity of soils ? What is pore space? 6. Define the terms : 

 skeleton, fine earth, fine sand, silt, and clay. 7. What are the 

 physical properties of clay ? 8. What are the forms of the soil 

 particles ? 9. How do different types of soil vary as to the number 

 of particles per gram of soil ? 10. How is a mechanical analysis 

 of a soil made ? 1 1 . Why do certain crops thrive best on definite 

 types of soil ? 12. What factors must be taken into consideration 

 in determining the type to which a soil belongs ? 13. Give the 

 mechanical structure of a good potato soil. 14. How does a wheat 

 soil differ in mechanical structure from a truck soil? 15. A good 

 corn soil is also a type for what other crops ? 16. How much 

 water is required to produce an average grain crop, and how do the 

 rainfall and the water removed in crops during the growing season 

 compare? 17. In what forms may water be present in soils ? 18. 

 What is bottom water and when may it be utilized by crops ? 19. 

 What is capillary water ? 20. Explain the capillary movement of 

 water. 21. Explain how the capillary and non-capillary spaces in 

 the soil may be influenced by cultivation. 22. What is hydroscopic 

 water and of what value is it to crops ? 23. What is percolation ? 

 24. To what extent may losses occur by percolation ? 25. What 

 are the factors which influence evaporation ? 26. What is transpira- 

 tion ? 27. In what three ways may water be lost from the soil ? 

 28. Why does shallow surface cultivation prevent evaporation ? 



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