SOILS 



THEIR FORMATION, PROPERTIES, COMPOSITIOIT, 

 AND RELATIONS TO CLIMATE AND PLANT 

 GROWTH IN THE HUMID AND ARID REGIONS 



By E. W. HILGARD, Ph.D., LL.D. 



Professor of Agriculture in the University of California, 

 and Director of the California Agriculture JExperiment Station. 



Cloihy Svoj $4- 00 net 



SUMMARY OF CHAPTEES 



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I. Origin and Fobmation of Soils 



Ihteoduction 



Chapter 1. Physical Processes of Soil Formation. 

 Chemical Processes of Soil Formation. 

 Chief Soil-Forming Minerals. 

 The Various Kocks as Soil-Formers. 

 Minor Mineral Ingredients of Soil — Mineral Fertilizers- 

 Minerals Injurious to Agriculture. 



II. ~ 



Physical Composition of Soils. 



Density, Pore Space, and Volume-Weight of Soils. 



Soil and Subsoil —Causes and Processes of Differentiation — 

 Humus 



Soil and Subsoil— Organisms Influencing Soil-Conditions — 

 Bacteria. 



Soil and Subsoil in Their Kelations to Vegetation. 



Water of Soils — ^Hygroscopic and Capillary Moisture. 



Water of Soils — Surface, Hydrostatic, and Ground-Water 

 — Percolation. 

 " 13. Water of Soils— Conservation and Kegulation of Soil Moist- 

 ure — Irrigation. 

 " 14. Absorption by Soils of Solids from Solutions— Absorption 

 of Gases — The Air of Soils. 



Colors of Soils. 



Climate. 



Relations of Soils and Plant-Growth to Heat. 



III. Chemistry of Soils 



Chapter 18. Physico-Chemical Investigation of Soils in Kelation to 

 Crop Production. 

 " 19. Analysis of Virgin Soils by Extraction with Strong Acids, 

 and its Interpretation. 

 Soils of Arid and Humid Begions. 

 Soils of And and Humid Begions, Continued. 

 Alkali Soils, Their Nature and Composition. 

 Utilization and Beclamation of Alkali Lands. 



IV. Soils and Fatiye Vegetation 



Chapter 24. Becognition of the Character of Soils from Their Native 



Vegetation — Mississippi. 

 " 25. Becognition of the Character of Soils from Their Native 



Vegetation— United States at Large— Europe. 

 " 26. Vegetation of Saline and Alkali Lands. 



THE MACMILLAN CO., 64-66 Fifth Ave., N. Y. 



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