REPORT OF THE ENTOMOLOGIST. 215 



a 



Kerosene (the common lamp oil) 2 gallons. 



" Water 1 gallon . 



" Common washing soap J pound. 



" Heat the solution of soap, and add it boiling hot to the kerosene. 

 Churn or agitate the mixture by means of a force pump and spray 

 nozzle for five or ten minutes. The emulsion, if perfect, forms a 

 cream which thickens on cooling, and should adhere without oiliness 

 to the surface of glass. Dilute, before using, one part of the emul- 

 sion with nine parts of cold water. The above formula gives three 

 gallons of emulsion, and makes, when diluted, thirty gallons of wash." * 



Either of these formulae will give a wash of sufficient strength, if 

 properly applied, to kill both the insects and their eggs; and will 

 injure no foliage. 



Professor Cook says: " Many have complained of a lack of success 

 in the use of kerosene emulsion. In such cases, I presume the ex- 

 planation lies in the manner of making the application. We must 

 bear in mind that the lice are well concealed and protected by the 

 thousand leaves from which they are sucking the life, and a livelihood. 

 Often the leaves curl up and thus make the protection more sure. 

 But we must strike every louse or insect with the liquid. We cannot 

 then turn or sprinkle on the liquid gently, we must dash it on with 

 force, that every insect may be struck ; then there will be no complaint 

 of ill success. Thus the kerosene emulsion should always be applied 

 with a good force pump. It is doubtless better to throw all liquid 

 insecticides in spraying for injurious insects ; with the kerosene emul- 

 sion, it is absolutely essential to success. The kerosene emulsion is 

 superior to any other insecticide, so far as I have experimented in 

 destroying plant lice, scale or bark lice, many of the bugs, and not a 

 few caterpillars, grubs and slugs." 



With the above facts before him, the intelligent farmer will be able 

 to apply these several insecticides to the destruction of a great variety 

 of injurious insects that attack other plants than the trees growing 

 upon his premises. Of course, bearing in mind that the poisons 

 should never be used to destroy insects that work upon vegetables or 

 other articles of food. For these latter he can resort to the kerosene 

 emulsion and also to the 



* Insects Affecting the Orange, by H. G-. Hubbard, United States Department of 

 Agriculture, Division of Entomology, 1885, p. 94. 



