Index 



Johnson, F. E., acknowledgment 

 of assistance, 181. 



Kelley, W. P., 39. 



Kharkov wheat, effect of Califor- 

 nia conditions on protein con- 

 tent, 66. 



Lead, effects on ammonifying and 

 nitrif\-ing flora, 127; toxicity 

 to nitrifying flora, 136, to 

 other organisms, 137. 



Lead sulfate, effects on: nitrifica- 

 tion, 136, 546-549, barley 

 growth, 519, 561, 576-578, 

 plant growth, bibliography, 

 witli comments, 543-544. 



Lime, effect on nitrate determina- 

 tion, 31, 32. 



Lime magnesia ratio, effects on 

 ]ilants, 40. 



Lipman, C. B., 1, 21, 127, 141, 275, 

 495; cited on activity of soil 

 bacteria, 40, 179. 



Loughridge, E. H., 173; investiga- 

 tion of soil columns of Cali- 

 fornia, 1. 



Mackie, W. W., acknowledgment, 

 204. 



Magnesium, in iiercolate, relation 

 to colloidal diffusion, 309; 

 chemical studies of, 310; in- 

 creased bv application of 

 NaCl, 310.' 



Magnesium, and calcium, in salt- 

 treated soils, 311, 313. 



Magnesuim carbonates, effects on 

 ammonification and nitrifica- 

 tion in soils, 39. 



Manganese, effect on plant 

 growth, bibliography, with 

 comments, 544—546. 



Mana:anese chloride, effect on bar- 

 ley growth. 529, 562, 585-587. 



Manganese salts, effect on nitri- 

 fication in soils, 548. 



Mansranese sulfate, effect on bar- 

 ley growth, 525, 561, 582-584. 



Manure, goat, and sheen, culture 

 exyieriments, 142, 161. 



Mic. tetragenus, culture experi- 

 ments, 142. 



Mining detritus, damage to irri- 

 gated crops, 397, 398. 



Moss, killed by copper sulfate, 

 443. 



Neutral salts, effect on colloidal 

 matter, 317, 318. 



New Experiments on Alkali Soil 

 Treatment, 275. 



Nicotiana sylvestris, 345. 



tabacum var. macrophylla, 345. 



Nitrate production, stimulation of 

 arsenic, 129. 



Nitrates, in soils, determination 

 methods, 21, 51, 52, 53; inter- 

 fering factors in determina- 

 tions, 21, salts, 23-28, clay 

 precipitants, 28-31; losses: in 

 Pasteur Chamberland filter, 

 22, induced bv chlorides and 

 chlorines, 22," 23, 24, 28, 33, 

 35, 36, 37. 



Nitrification in soils, depth, 11, 

 12; effects of calcium and 

 magnesium carbonates, 45, 46, 

 47; soil used in experiments, 

 45; description of experi- 

 ments, 132; effects of Cu, Zn, 

 PE and PB, 133-137, 546- 

 549; physiological differences 

 between ammonifying and 

 nitrifving flora, 137; stimu- 

 lating eft'ect of Cu, Zn, PE, 

 and PB, on nitrifving flora, 

 138, 139. 



Nitrites, effects of magnesium 

 carbonate on formation, 48. 



Nitrogen, supply in soil depths, 

 7, 10, 13; in typical as 

 against spotted wheat ker- 

 nels of the same variety, 69; 

 effect on protein content of 

 wheat, 122; form of, in hu- 

 mus and in soil, 258, 260; 

 physiological effect on to- 

 bacco, 348, 352-355; content 

 in barley, 550, 562. 



Nutrient salts, injury due to ex- 

 cess or deficiency, 362. 



Nutrient solution, influence of 

 composition and concentra- 

 tion on plants grown in sand 

 cultures, 341 ; effect on flower 

 production in tobacco, 354; 

 absorption of salts from, by 

 plant, 366. 



Peptone, culture experiments, 142, 

 161. 



Percolation, in soils, 296-300; 

 varies inversely as degree of 

 diffusion, 303; retarded bv 

 llCl, 314. 



Phenoldlsulphonic Acid Method 

 for Determining Nitrates in 

 Soils, Studies on the, 21. 



Phenoldisul))hnnic acid method 

 for nitrate determination, in- 

 terfering factors, 21; need 

 for uniform compound, 22; 

 ]ire]iaration of trinotassium 

 salt of nitrophenoldisulphonic 

 acid, 22; compared with alu- 

 minum reduction method, 55. 

 See also Nitrates. 



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