xiv CONTENTS 



CHAPTER VI 



Experiments upon Oats 



PAGE 



Experiments upon Oats Grown Continuously upon the same Land, 



Geescroft Field . . . . . .92 



CHAPTER VII 



Experiments upon Root-Crops Grown Continuously on the 

 SAME Land. 



I. Experiments upon Mangels, Barnfield, 1876-1904 . . 96 



A. Effect of Nitrogenous Manures .... 99 



B. Effect of Mineral Manures . . . . .103 



C. Comparison of Nitrate of Soda and Ammonium-salts as 



sources of Nitrogen . . . . .107 



D. Effect of Nitrogenous and Mineral Manures when used in 



conjunction with Dung . . . . .108 



E. Proportion of Root to Leaf . . . .112 



F. Proportion of the Nitrogen recovered in Crop to that 



supplied in Manure . . . . .112 



G. The Composition of the Mangel Crop as affected by 



Manuring . . . . .11-5 



Practical Conclusions . . . . . .119 



II. Experiments upon Turnips, Barn Field, 1843-1870 . . 119 



Practical Conclusions . . . . . . 1J2 



III Experiments on the Continuous Growth of Potatoes on the same 



Land, Hoos Field, 1876-1901 . . . . .122 



Practical Conclusions . . . . . .126 



IV. Experiments on the Growth of Sugar Beet, Barn Field . . 127 



A. First Series, 1871-75 ..... 127 



B. Second Series, 1898-1901 ..... 130 

 Practical Conclusions and References . . . .132 



CHAPTER VIII 



Experiments upon the Continuous Growth of Leguminous 

 Crops 



I. The Continuous Growth of Beans on the same Land, Geescroft 



Field 133 



II. The Continuous Growth of Red Clover on ordinary Arable Land, 



Hoos Field ....... 141 



III. The Continuous Growth of Clover on rich Garden Soil . . 144 



References . . . . . . . .149 



