204 GARDE]S^ING FOR PLEASURE. 



roots are completely surrounded by the Blue Aphis. The 

 only remedy we have ever found for this pest is a strong 

 decoction of tobacco, made so strong as to resemble black 

 coffee in color. The earth around the plants must be 

 soaked with this, so that the lowest roots will be reached. 

 The tobacco water will not hurt the plants, but will be 

 fatal to the insect, and, if it has not already damaged 

 the roots to too great an extent, may prove a remedy. 



Ants. — These are not usually troublesome in the open 

 ground, unless on lawns. (For remedies there see Chap- 

 ter on ^"Lawns.") In greenhouses, however, they are one 

 of the worst pests, not so much from the injury they do 

 themselves as by their carrying mealy bug, green fly, and 

 other insects, so that from one plant thus affected the 

 ants will soon distribute them over all the plants in the 

 greenhouse. A simple method we have found to get rid 

 of them, is to lay fresh bones around the infested plants. 

 They will leave everything to feed on these, and when 

 thus accumulated may be easily destroyed. Another 

 method is to blow Pyretlirum or Persian Insect Powder 

 over them with a bellows. They are killed at once if the 

 powder strikes them in a dry state ; but it has no effect 

 if damp, for, when strewed in their haunts, they run over 

 it with impunity. 



The Red Spider is one of the most insidious enemies 

 of plants, both when under glass and in the open air in 

 summer. It luxuriates in a hot and dry atmosphere, 

 and the only remedy that I can safely recommend to am- 

 ateurs is copious syringings with water, if in the green- 

 house, so that a moist atmosphere can be obtained. This, 

 of course, is not practicable when plants are grown in 

 rooms, and the only thing that can then be done is to 

 sponge off the leaves. It is this insect, more than any- 

 thing else, that makes it so difficult to grow plants in the 

 dry air of the sitting-room, as it may be sapping the life 

 blood from a plant, and its owner never discover the 



