236 



INDEX 



Nitrogen-fixing bacteria, 96 

 Nitrogen, forms of, lOO 

 Nitrogen, how brought to soil, 



Nitrogen, how maintained in soil, 



180, 181" 

 Nitrogen, in atmosphere, lOO 

 Nitrogen, in feeds, 2 1 

 Nitrogen, in irrigation water, 223 

 Nitrogen, in legumes, 176, 177 

 Nitrogen, in manure, 211 

 Nitrogen in Utah soil, 173 

 Nitrogen liberated in war, loi 

 Nitrogen losses from manure, 212 

 Nitrogen losses due to Irrigation 



water, 222 

 Nitrogen losses, early Ideas of, 



132, 133 



Nitrogen obtained from atmos- 

 phere, 175, 176 



Nitrogen, organisms fixing, 141, 

 142 



Nitrogen, requirements of bac- 

 teria, 58 



Nitrogen, requirements of plants, 



87 



Nitrogen, soil gains in, 149, 151- 



15s 



Nitrogen, synthetic, 139 



Nitrogen, transformations of in 



soil, 132 

 Nitrogen, value of, 173, 174 

 Nitrosococcus, 122 

 Nomenclature, 37 

 Nucleus, 31 



o 



Oats, Influence on nitrification, 

 128 



Organic matter, changed by bac- 

 teria, 1 07-1 17 

 Organic matter, composition, 109 

 Organic matter, function in soil, 



108 

 Organic matter, influence on soil 



temperature, 109 

 Organic matter, Influence on soil 



water, 109 

 Organic matter, kinds In soil, 108 

 Organic matter, origin of In soil, 



108 

 Organic matter, quantity In soil, 



107 

 Organic matter, value in soil, 1 07- 



108 

 Osmotic pressure, 67 

 Oxygen, influence on nitrification, 



124 

 Oxygen, Influence on nitrogen 



fixation, 160 

 Oxygen, influence on denitrlfica- 



tlon, 136 

 Oxygen, requirements of bacteria, 



59 



P 



Pasteur, 6, 7, 98 

 Parasitic bacteria, 56 

 Pathogenic bacteria, 56 

 Peat "bacterized," 150 

 Pettenkoffer, 98 

 Phosphorus cycle, 102-106 

 Phosphorus in feeds, 2 1 

 Phosphorus in manure, 211 

 Phosphorus In soil, 80 

 Phosphorus In Utah soil, 173 

 Phosphorus in water, 223 



