INDEX 



255 



Tilth, as affected by lime, 189. 



in relation to drainage, 79. 



relation to structure, 39. 

 Toxic substances and crop rotation, 



246. 

 Transpiration, as affected by soil 

 moisture, 69. 



by different crops, 69. 



conditions affecting, 70. 



ratio, 69. 



relation to soil fertility, 70. 



test for loss by, 88. 

 Transported soil, 18. 

 Type, the soil, in soil survey, 44. 



Vegetables, fertilizers for, 209. 



Water, as a soil transporting agent, 

 13. 



capillary, capacity of soils, 63. 



capillary, definition, 62. 



capillary, effect of structure on 

 movement of, 65. 



capillary, effect of texture on 

 movement of, 65. 



capillary, height of column and 

 movement, 66. 



capillary movement and plant re- 

 quirement, 71. 



capillary, movement of, 64. 



capillary, properties of, 63. 



carrying power for rock debris, 13. 



control of soil content, 72. 



effect on rock disintegration, 12. 



evaporation from soil, 73. 



Water, expansive power in freezing, 

 12. 



forms in soils, 61. 



gravitational, definition, 62. 



gravitational, movement, 67. 



gravitational, properties of, 66. 



hygroscopic, definition, 61. 



hygroscopic, properties of, 62. 



in soil, determination of per cent, 

 85. 



optimum content for plant growth, 

 71. 



percolation through soil, 73. 



quantity required to mature a crop, 

 70. 



relation to plants, 67. - 



requirements of plants, 68. 



run-off, 72. 



solvent action on rock, 12. 



test for capacity of soil for, 87. 



test for capillary movement, 86. 



test for conservation by mulch, 87. 



test for loss by transpiration, 88. 



test for rate of percolation, 86. 



uses by plants, 2. 



ways in which useful to plants, 68. 

 Water-soluble matter in soil, 96. 



test for, 111. 

 Water table, 67. 



Weeds that flourish on acid soils, 115. 

 Wetting and drying soil, affect on 



structure, 40. 

 Wind, action in transporting soil, 14. 



erosive action on rocks, 14. 

 Windbreaks, to decrease evaporation, 

 78. 



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