The Story-Book of the Fields 



followed by one that is restorative ; a plant 

 with poor leaves by one whose leaves are 

 highly developed. The principal restorative 

 plants are clover, lucerne, sainfoin, the 

 potato, beetroot and turnip. Cereals, on the 

 other hand, are all exhaustive plants. 



Generally a series of different plants is grown 

 on the same ground. This series comes to 

 an end in four, five, six or more years, and 

 then begins again in the same order. The 

 following is an example of a six-years' 

 rotation : 



ist year 

 2nd year 

 3rd year 

 4th year 

 5th year 

 6th year 



We will consider this rotation as an ex- 

 ample. In the first year the ground is 

 thoroughly manured. One effect of the 

 manure is the appearance of a number of 

 weeds which would infect the ground and im- 

 poverish the crop unless they were carefully 

 removed. Hence the necessity of weeding. 

 The weeds are removed either by hand or 

 with an implement. It is not possible to weed 



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