CONTENTS 



BOOK I. SOILS AND SOIL MANAGEMENT 



Chapter 1. SOIL CLASSIFICATION AND CROPJLDAPTATION 33 



Soils are permanent — What farmers should know — The science of the soil — How 

 soils are formed — Weathering and disintegration — Decomposition — What is the 

 soil — The soil solids — The soil fluid — Gases of the soil — Soil classification — Soil 

 surveys — Soils of the United States — Classification by texture — Crop adaptation- 

 Summary of soil adaptedness — Eastern soils not worn out — Soil adaptation of six- 

 teen crops common to Northeastern States — Soil adaptation of the leading crops 

 of the North Central Region, South Central and South Atlantic Coast Region, 

 Plains and Mountain Region, Pacific Coast Region — Aids to the solution of soil 

 problems. 



Chapter 2. PHYSICAL, CHEMICAL AND BIOLOGICAL PROPERTIES 51 



Texture of soil — Water-holding capacity of soils — Water movement in soil — Absorp- 

 tion of fertilizers — Plasticity and ease of cultivation — Texture affects crop adapta- 

 tion — Texture affects tillage — Structure of the soil — Granular structure — Granula- 

 tion improved by organic matter — Good tilth important- — Solubility of soil 

 minerals — Rate of solubility depends on texture and kind of minerals — Soil bacteria 

 increase solubility — Rapid solubility results in loss of fertility — Chemical composi- 

 tion of soils — Availability important — Elements essential to plants — Soil bacteria- 

 Bacteria make plant food available — Nitrogen increased by bacteria — Bacteria 

 abundant near surface. 



Chapter 3. FERTILITY AND HOW TO MAINTAIN 62 



Fertility defined — Vegetation an index to fertility— Drainage reflected in character 

 of vegetation— Lime content and acidity related to plants — Vegetation and alkali — 

 Color of soil related to fertility — Maintenance of fertility — Fertility lost by plant 

 removal — Loss by erosion — Preventing soil erosion — Farming systems that main- 

 tain fertility — Deep plowing advisable— Tillage is manure — Rotations are helpful — 

 Rotations reduce diseases — Cover crops prevent loss of fertility — Legumes increase 

 soil nitrogen — Drainage increases fertility — Manure is the best fertilizer — Commer- 

 cial fertilizers add plant food only — The limiting factor — Fertility an economic 

 problem. 



Chapter 4. COMMERCIAL FERTILIZERS 72 



Object and use of commercial fertilizers — What are commercial fertilizers — Where 

 are fertilizers secured — Carriers of nitrogen — Phosphorus — Potassium — Forms of 

 fertilizer materials — Relative value of fertilizer ingredients — The composition of 

 fertilizers — What analyses of fertilizers show — Commercial vs. agricultural value of 

 manures — Mechanical condition — High-grade vs. low-grade fertilizers — Use of 

 fertilizers — Value of crop determines rate of fertilization — Valuable products 

 justify heavy fertilization — Character of fertilizer related to soil — What the farmer 

 should know — How to determine needs of soil — Effect modified by soil and crop — 

 Which is the best fertilizer to use — Needs of different soils — Crop requirements- 

 Fertilizers for cereals and grasses — Legumes require no nitrogen — Available forms 

 best for roots — Slow-acting fertilizers suited to orchards and small fruits — Nitrogen 

 needed for vegetables — Fertilizers for cotton — Miscellaneous fertilizer facts — Effect 

 of fertilizers on proportion of straw to grain — Principles governing profitable use of 

 fertilizers — When to apply fertilizers — Methods of application — Purchase of fertili- 

 zers — Home mixing of fertilizers. 



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