Habits of Growth. by 



any disturbing action is brought to bear 

 upon these root-stocks, as, for example, 

 breaking them oft" from their parent stem 

 by the implements of tillage, a fresh impulse 

 is given to their growth. Each rootlet so 

 severed attempts to develop into a complete 

 plant. Hence it is that, in moist weather, 

 ordinary cultivation is more likely to pro- 

 mote than hinder the growth of this class 

 of weeds. The influence of summer-fallows 

 and of cultivated crops which are poorly 

 cared for, is also in the same direction. 

 Creeping perennials are also likely to cling 

 to the implements of tillage, and thus be 

 carried from one part of the field to another, 

 and even to other fields. The Canada this- 

 tle, the common sow thistle, and quack 

 grass furnish familiar examples of creep- 

 ing perennials ; and we are sure the experi- 

 ence of our readers will bear us out in what 

 we have just said of the tendency of culti- 

 vation, in moist weather, to promote their 

 increase. 



To destroy creeping perennials we must 

 labor either to smother them, or else by 

 cultivation to bring their roots to the sur- 

 face, where they will perish by exposure to 

 the air and sunshine. By "smothering" 



