CHAPTER XII 



ROTATION OF CROPS AND CONSERVATION OF SOIL 



FERTILITY 



328. Object of Crop Rotation. The object of system- 

 atic rotation of crops is to conserve the fertility of the 

 soil and at the same time to produce maximum yields. 

 In order to accomplish this, the food requirements 

 of different crops must be met by good cultivation 

 and judicious manuring. Rotations must be planned 

 according to the nature of the soil and the system of 

 farming that is to be followed. For general grain 

 farming a different rotation is required than for ex- 

 clusive dairying. Whatever the nature of farming, the 

 whole farm should gradually undergo a systematic ro- 

 tation. If the farm is uneven in soil texture, different 

 rotations may be practiced on the various parts. There 

 is no way in which soils are more rapidly depleted of 

 fertility than by the continued culture of one crop. In 

 exclusive wheat raising, for example, the losses are not 

 confined to the fertility removed in the crop, but other 

 losses occur as described in the chapter on nitrogen. 

 When wheat is systematically grown in alternation with 

 other crops, losses of nitrogen are reduced to the mini- 

 mum. 



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