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CONTENTS. 



PAGE. 



Introduction 5 



Manufacture of Sulphate of Ammonia 5 



Substances Essential for Plant Growth 6 



Natural Supplies of Nitrogen to the Plant 6 



Losses of Nitrogen from the Soil 7 



Increase from Nitrogenous Manuring 7 



Do Nitrogenous Manures Impoverish the Land ? . . . . 9 



Effect of Nitrogenous Manures on the Plant 10 



How Nitrogen is Taken Up by Plants it 



Absorption of Ammonia by Soils 12 



Possible Loss of Ammonia when Applied as Sulphate . . 14 



Nitrification 15 



Conditions necessary for Nitrification 15 



Conditions preventing Nitrification 17 



Rapidity of Nitrification 18 



Loss of Nitrates 19 



Influence of Climate and Season on the Effect of Sulphate 20 



Time of Year to Apply Sulphate 21 



Stage of Growth Best for the Application of Sulphate . . 24 



Use of Sulphate on Different Soils 26 



Residue from Sulphate of Ammonia 27 



Effect of Applying too much Sulphate 29 



Effect of Sulphate of Ammonia on the Soil 30 



Method of Applying Sulphate 31 



Composition of Sulphate of Ammonia 32 



Cost and Valuation of Sulphate 33 



Impurities and Adulterants 34 



Effect of Sulphate on Individual Crops 34 



Wheat 35 



Sulphate for Continuous Wheat Growing .... 35 



Sulphate for Wheat in Rotation 38 



Barley 40 



Effect of Sulphate on Yield 40 



Effect of Sulphate on Quality 42 



Oats 45 



Mangels 47 



Effect of Sulphate on Yield 48 



Effect of Sulphate on Feeding Value 48 



Sulphate for Mangels in Rotation 50 



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