The Pests of Garden Plants 



tobacco in hot water at the rate of four ounces to the gallon, and 

 add a little size. To economise this mixture it is advisable to dip 

 the plants ; but if this is not practicable, syringe them, taking care 

 to wet the leaves on both sides. We have seen Plum trees literally 

 blue with Aphis rendered perfectly clean by a solution of common 

 glue, in the proportion of a quarter of a pound to the gallon of water, 

 with a little flowers of sulphur added. After being well wetted with 

 this cheap mixture, the trees shone as if varnished, and the mixture 

 was not washed off, because it cracks and peels off naturally, and the 

 trees, being freed from fly, resumed vigorous growth. Rose trees 

 may generally be cleansed of fly by means of the garden engine 

 and pure water only, the essential point being to direct the water on 

 the trees with some amount of force for several evenings in succes- 

 sion whenever the fly threatens to obtain the mastery. Quassia is 

 often used instead of tobacco, but it is uncertain in its operation, 

 and therefore, although we know it is at times effectual, we cannot 

 give it a general recommendation. The same may be said of 

 Socotrine aloes, which sometimes kills the fly, and sometimes leaves 

 it unhurt. These drugs vary in quality, but strong tobacco never 

 fails to do its appointed work. 



Soft soap dissolved in water makes a cheap and effectual wash 

 for exterminating all kinds of Aphis. Pot plants can be dipped in it 

 as already advised, or the solution may be applied by means of the 

 syringe. On the following day the plants should be cleansed with 

 pure soft water. An emulsion is also made from soft soap and 

 mineral oil, but we allude to it with considerable trepidation. When 

 properly mixed and skilfully 

 applied there is no question 

 about its deadly effects on 

 insect life. The danger of 

 using it lies in the fact that 

 the two articles do not readily 

 combine, and an application 

 of pure paraffin is as disastrous 

 to foliage as a fire. 



X IO- ^ 



BEAN APHIS 

 The Bean AphiS, also Aphis fala> (pupa and female) 



known as the Bean Plant 



Louse, or Black Dolphin (Aphis fafa, Scop.). Our illustration 

 shows the wingless female and pupa natural size and magnified. 

 The pupa is black with greyish white mottlings, whilst the female is 



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