CHAPTER VIII 



WEEDS 



IN all gardening and agricultural operations the careful 

 cultivator makes it his constant care to destroy weeds. 

 These are wild plants which invade the cultivated land 

 and impede the growth of the crop. Weeds act injuri- 

 ously in several ways. They crowd out cultivated crops 

 by their leaves overshadowing and robbing the crop of 

 the necessary sunlight, which as we have seen, plants 

 make efforts to secure, being essential to their growth. 

 The roots of the weeds rob the soil of moisture, thus 

 retarding the crop's growth. At the same time the 

 weeds use up some of the available plant food, thus 

 leaving the crop insufficiently fed. This is particularly 

 the case with the nitrogen, as when there are many 

 weeds in the soil their roots compete with those of the 

 crop in taking up the nitrates as fast as they are formed 

 in the soil, and thus the crop may be unable to secure a 

 sufficient supply for the purposes of vigorous growth. 



When a piece of land is newly brought under culti- 

 vation much trouble is often experienced in removing 

 the weeds, which grow from the seeds lying dormant in 

 the soil, and from others brought there by the wind, or 



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