428 



INDEX 



Gilbert with Lawes, transpiration, 



188 



Glacial and loessial province, 84 

 drift, gravelly phase, 41 

 grooves, striae, 43 

 lake and river terrace province, 



89 

 lakes, 50, 51 



extent of, 46 

 or ice-laid deposits, chapter on, 



41 



period, 45 



scratches on boulder, 42 

 stream, alluviation by, 62 

 Glaciation, extent of, in North 



America, map of, 46 

 in Europe, map of, 48 

 Glaciations, Illinoisan, 47 

 lowan, 48 



Jerseyan or Nebraskan, 46 

 Kansan, 46 

 Wisconsin, Early, 50 



Late, 50 



Glacier, Chenega, 41 

 Columbia, front, 15 



over-riding forest, Alaska, 14 

 defined, 16 



factor in weathering, 15 

 incidental features, 50 

 pressure of ice, 16 

 Grand Canon, Colorado River, 17 

 Granite, 7 



exfoliated, California, 13 

 wind-carved, 18 

 Oranulation, effect of drainage on, 



222 



of organic matter on, 148 

 of, on percolation, 218 

 Grass, beach or Marram, transplant- 

 ing, 56 



bunch, holds sand, 60 

 Gravel and gravelly loams, 139 

 Gravelly loams, 116 

 Gravels, 116 



Gravitational water, chapter on, 217 

 Gravity-laid soils, 30 

 Great Basin region, 106 



Plains region, 100 

 Green manures, 160 

 Growth and germination, effect of 



drainage on, 223 

 color of soils on, 303 

 of plants, limit of alkali for, 



284 



temperature for, 297 

 Guide-row terrace, 365 

 Gulf Coastal Plains, and Atlantic, 91 



Gullying, methods of prevention and 

 filling, dams, 371 



soil, 374 



straw and brush, 370 



vegetation, 374 

 Gypsum, 5 



Haberlandt, time required for ger- 

 mination at different tempera- 

 tures, 297 



Hall, A. U., rainfall and evapora- 

 tion, Rothamsted, 211 

 table, rainfall, percolation, evap- 

 oration, Rothamsted, 220 

 temperature of soil for growth, 



298 

 yield of wheat with percolation 



large and small, 153 

 Hardness of minerals, 2 

 Hardpan, 69 



effect of, in alkali lands, 290 

 Harrows, acme or blade, 333 

 disk, 334 

 spike- tooth, 331 

 spring-tooth, 332 

 Hay and pasture province, rotation 



for, 386 



Heat, absorption and radiation of, 

 effect on soil temperature, 302 

 and cold, factor in disintegra- 

 tion, 12 

 conduction downward into soil, 



source of loss, 296 

 soil, sources of, 293 

 specific, affecting soil tempera- 

 ture, 298 



effect of moisture on, 300 

 of common substances, 299 

 of soil constituents, 299 

 of soils, 300 



to penetrate soil, time for, 306 

 Heaving, due to lack of drainage, 



225 



of alfalfa, 226 

 "Heavy" soil, denned, 134 

 Hellriegel, water transpired per 



pound of dry matter, 188 

 Hematite, 5 

 Hilgard, E. W., changes in organic 



matter, 146 

 churn elutriator, 126 

 composition of salts in alkali 



spot, 282 



of typical alkali salts, 280 



effect of various substances on 



hygroscopic capacity, 195 



