«*. 



TABLE OF CONTENTS 



CHAPTER FAGS 



I. Some Conceptions op the Soil and Its Relation to 



/^ Plants 1 



*\JX- Soil Forming Processes 16 



*^III. The Geological Classification op Soils 38 



IV, The Soil Particle and Certain Important Relations 66 



V. The Organic Matter op the Soil 99 



VI. The Colloidal Matter op the Soil 127 



•*vll. Soil Structure and Its Modification 139 



lafSTfT The Forms op Soil Water and Their Characteristics 151 



IX. The Water of the Soil in Its Relation to Plants . 184 



\XT The Control op Soil Moisture 202 



XI. Soil Heat 223 



XII. Soil Air 247 



XIII. The Absorptive Properties o* Soils 263 



XIV. The Soil Solution 275 



XV. The Removal op Nutrients prom the Soil by Cropping 



and Leaching 289 



^■XVl. Chemical Analysis op Soils 311 



VKVII. Alkali Soils 328 



V^VIII. Soil Acidity 345 



XIX. Liming the Soil 362 



«- X X. Soil Organisms, Carbon, Sulfur and Mineral Cycles 384 



sJLxxi. Soil Organisms — the Nitrogen Cycle 409 



XXII. Commercial Fertilizer Materials 442 



XXIII. The Principles of Fertilizer Practice 471 



XXIV. Farm Manure t 499 



XXV. Green Manure 535 



XXVI. The Maintenance of Soil Fertility 552 



Index of Authors 561 



Index of Subject Matter 567 



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