XXviii CONTENTS. 



Period of growth 489 



Variation in composition of crops . . . . .490 



Absorption of plant-food ....... 490 



Fertilising ingredients lodge in the seed .... 491 



Forms in which nitrogen exists in plants 491 



Bearing of above on agricultural practice .... 492 



Influence of excessive manuring of crops . . . . .492 



CHAPTER XXIII. MANURING OF THE COMMON 

 FARM CROPS. 



Cereals ........... 493 



Especially benefited by nitrogenous manures . . . 494 

 Power of absorbing silicates . . . . . .494 



Barley 495 



Period of growth ....... 495 



Most suitable soil ....... 496 



Farmyard manure not suitable 497 



Importance of uniform manuring of barley . . 497 



Norfolk experiments on barley 497 



Proportion of grain to straw . . . . .498 



Wheat 499 



Rothamsted experiments ....... 500 



Continuous growth ....... 500 



Flitcham experiments . . . . . . .500 



Oats 501 



A very hardy crop ....... 502 



Require mixed nitrogenous manuring . . . .502 



Arendt's experiments 503 



Aveniue ......... 503 



Quantities of manures ...... 504 



Grass 504 



Effect of manures on herbage of pastures . . . .505 



Influence of farmyard manure . . . . . .506 



Influence of soil and season on pastures .... 507 



Manuring of meadow land ...... 508 



Baiigor experiments . . . . . . .508 



Norfolk experiments . . . . . . 509 



Manuring of permanent pastures ..... 509 



Roots .510 



Influence of manure on composition . . . .512 

 Nitrogenous manures increase sugar 512 



