ENEMIES OF PLANTS 



can escape when the entire plant is submerged. 

 I would advise giving badly-infested plants a 

 bath of this kind, at the beginning of the fight. 

 After once freeing them from the enemy they 

 can be kept free by using the extract occasion- 

 ally thereafter, more as a preventive than a 

 cure. The smell given off by it, in spraying, 

 is not strong enough to be very unpleasant, 

 and it is speedily dissipated by admitting fresh 

 air to the room. We therefore need fear the 

 aphis no longer. True, it is some trouble to 

 prepare the infusion, and some expense is con- 

 nected with it, but these items are so slight, 

 as compared with the benefits resulting, that 

 no lover of flowers has any excuse for allowing 

 her plants to be injured by this universal pest. 

 I am often asked: Where does the aphis 

 come from ? I do not know. I have seen col- 

 lections of plants that were apparently free 

 from it to-day, and to-morrow hundreds could 

 be found on them, and these would seem, in 

 three days' time, to have been multiplied by 

 thousands. And yet no new possibly infected 

 plant had been added to the collection. Where 

 they had come from, or how they came no one 

 could say. All that could be said was that 

 they were there, and had come to stay, unless 



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