30 SEASONAL NITRIFICATION AS INFLUENCED BY CROPS, ETC. 



Page. 

 Matter, soluble organic, in soil, cause of error in determination of nitrates. ... 10 

 Moisture, precipitation, and nitrates in experimental plats, comparative varia- 

 tion 19-20 



Montanari, C, remarks on quantity of "nitric nitrogen " in soil 25 



Nitrates, determination, three sources of error 10 



in dry soil treated in various ways 11 



experimental plats, disappearance 21-22 



fallow, spring- wheat, and corn plats, comparison 16-17 



soil, decrease, causes 25 



. spring- wheat plat, variation , 14-16 



wheat plat, removal, comparison with fallow plat 15 



moisture, and precipitation in experimental plats, comparative varia- 

 tion 19-20 



nitrites, and ammonia in soil, extraction, results of various methods. . 11 



variations in plats of different crops 12-27 



water-soluble, change to albuminoid nitrogen 25-26 



disappearance 25-26 



withdrawal by corn roots 17-18 



Nitiification, factors causing check 20 



maximum, period required for development 23-24 



relation to field factors 18-21 



summer fallow 26-27 



seasonal variations 23-25 



soil, effect of plowing 15 



relation of moisture : 24-25 



remarks of L. von Bazarewski 24 



Nitrites in dry soil treated in various ways 11, 22-23 



nitrates, and ammonia in soil, extraction, results of various methods 11 



Nitrogen, albuminoid, change from water-soluble nitrates 25 



content, crops, increase with increased nitrifying activity in soil 18 



soil, effect of organic food for nitrifying organisms 24 



virgin and cropped 25-26 



fixation, statement of P. Schneider 24 



nitric, quantity in soil, remarks of C. Montanari 25 



Organic matter. See Matter. 



Plats, experimental, description 8 



field history 9 



Plowing, effect on nitrification in soil 15 



method on experimental plat 9 



Precipitation, moisture, and nitrates in experimental plats, comparative 



variation 19-20 



Prairie, handling lands, establishment of experiment stations 7 S 



sod, experimental plats, description 9 



Roots, corn, withdrawal of nitrates 17-18 



Salts, alkali, presence in soil a cause of error in determination of nitrates 10 



Schneider, P. , nitrogen fixation, statement 24 



Sedges, occurrence in sod of experimental plat 9 



Soil, behavior of bacteria 28 



dry, amounts of nitrites and ammonia found 22-23 



experimental plats, aeration 23 



cracks 23 



description 8 



173 



