CONTENTS 



CHAPTER I 



PAQEB 



Soil as a Medium for Plant Growth . . . 1-7 



Soil as a mechanical support for plants, § 1 ; Soil 

 as a reservoir for water needed by plants, § 2 ; Uses 

 of water by plants, § 3 ; Soil as a source of plant-food 

 materials, § 4 ; Quantities of plant-food materials in 

 the earth's crust, § 5 ; Soil-forming rocks, § 6 ; Rock- 

 forming minerals, § 7 ; Important minerals, § 8. 



Questions on Chapter I ...... 7-8 



Laboratory Exercises ....... 8-10 



Study of soil-forming minerals, I ; Study of soil- 

 forming rocks, II ; To show that plants give off 

 water, III; Conditions for plant growth, IV; Ef- 

 fects of different plant nutrients, V. 



CHAPTER II 



Soil Formation and Transportation . . . 11-16 



Agencies concerned in soil formation and trans- 

 portation, § 9 ; Action of heat and cold, § 10 ; Ac- 

 tion of frost, § 11 ; Action of water, § 12 ; Action of 

 ice, § 13 ; Action of wind, § 14 ; Action of gases, 

 § 15 ; Action of plants and animals, § 16 ; Powdered 

 rock is not soil, § 17. 



Questions on Chapter II • 16 



Laboratory Exercises ....... 17 



Soil formation and transportation, I. 



CHAPTER III 



Soil Formations 18-28 



Residual soils, § 18 ; Distribution of residual soils, 

 §19; Cumulose soils, §20; Colluvial soils, §21; 



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