348 



INDEX 



ture, 313; on moisture, 313; in- 

 fluenced by foods, 162; influenced 

 by age and kind of animal, 169; 

 leaching of, 175; liquid, 164; 

 mixing of, 173; solid, 164; and 

 soil water, 45, 112; and tempera- 

 ture, 48; preservation of, 175; 

 use of, 181, 184; use of, in rotation, 

 278; value of, 189; volatile prod- 

 ucts from, 173. 



Manurial value of foods, 167. 



Manuring, of crops, 185; pasture 

 land, 183. 



Marl, 228. 



Mechanical, analysis of soils, 19; 

 condition of fertilizers, 238; compo- 

 sition of soil types, 27. 



Methods of farming, influence of, 

 upon fertility, 114. 



Mica, 66. 



Micro-organisms and soil formation, 

 54, 60. 



Mineral matter and humus, 109. 



Mixing manures, 173. 



Moisture for nitrification, 139. 



Movement of water after rains, 39. 



Muck, 153, 161. 



Mulching, 42. 



Nitrate of soda, 154. 



Nitric nitrogen, 154. 



Nitrification, 135; conditions neces- 

 sary for, 1 36 ; elements essential 

 for, 140; and plowing, 145; and 

 sunlight, 139. 



Nitrogen, assimilation, 1 1 8, 121; of 

 clover plant, 122, 125; as plant 

 food, 116; compounds of soil, 76; 

 compounds, solubility of, 323; 

 deficiency of, in soil, 249; gain of, 

 in soils, 133-134; loss of, by 

 fallowing, 144; losses of, from soil, 

 132; ratio of, to carbon, 131; re- 

 moved in crops, 128; in com- 

 mercial fertilizers, 238; in rain 



water and snow, 131; amount of, 



in soils, 128; in organic forms, 127; 



as nitrates, 129; as nitrites, 129; 



availability of, 127; forms of, 126; 



origin of, 126. 



Nitrogenous manures, 146, 157. 

 Number of soil particles, 19. 



Oats, food requirements of, 262. 



Odor of soils, 51. 



Organic acids, action of, upon soils, 

 84, 85. 



Organic compounds of soil, classifi- 

 cation of, 103; source of, 102. 



Organic nitrogen, 147, 152. 



Organisms, ammonia-producing, 141; 

 of soil, 141; nitrous acid, 140; 

 nitrifying, 137; products of, 142. 



Orthoclase, 65. 



Osborne, 20. 



Oxidation of soil, 48. 



Oxygen compounds of soil, 77. 



Oxygen, necessary for nitrification, 138. 



* 



Pasteur, 8. 



Peat, 153, 161. 



Percolation, 32. 



Permanent meadows, manuring of, 

 268. 



Permeability of soils, 44. 



Phosphate fertilizers, 198; commer- 

 cial forms, 20 1 ; manufacture of, 

 204; as plant food, 198; removed 

 by crops, 199; reverted, 202; 

 rock, 203; slag, 206; use of, 205. 



Phosphoric acid, of commercial fer- 

 tilizers, 201, 239; available, 198, 

 203, 210; acid in soils, 200; defi- 

 ciency of, 250; removal in crops, 

 199; soluble and insoluble in soils, 

 84; testing for, 323; value of, 205. 



Phosphorus compounds of soils, 75. 



Physical, analysis of soils, 316. 



Plant food, classes of, 80; ash and 

 fertilizers, 256; distribution of, 93, 



