FRIENDS AND ENEMIES OF PLANTS 

 The following emulsion is highly recommended: 



181 



Soap 



Soft water 

 Kerosene 



1 gal. 



2 gal. 



Shave the soap into the soft water and bring to the boiling 

 point. When the soap is dissolved, pour in the oil and agitate 

 vigorously until a white, creamy emulsion is formed. When 

 ready to use, add seventeen gallons of water and spray the solu- 

 tion on the bodies of the insects to be killed. 



Sprays of tobacco, tea, pennyroyal, or volatile oils sometimes are 

 found very satisfactory. In other cases tobacco smoke and fumes 

 or poisonous gases are found effective. Fumes from hydrocyanic 

 acid are frequently used in treating San Jose scale. In bins and 

 seed chests carbon bisulphide may be used to good advantage if 

 these receptacles are air-tight, but this liquid is very inflammable 

 and must be kept away from the fire. Ant beds may be broken 

 up by repeated applications 

 of carbon bisulphide and 

 gasolene. Bear in mind 

 that gasoline is very de- 

 structive to all kinds of 

 vegetation with which it 

 comes in contact. 



Soft-bodied insects may 

 frequently be killed by ap- 

 plications of lime or wood 

 ashes, which should be care- 

 fully dusted over the in- 

 fected plants. Sprays of 

 very dilute carbolic acid are 

 also helpful in such cases. 



Predaceous and Parasitic 

 Insects. These are in- 

 sects that prey upon other Cabba ? e butterf] y and larva 

 insects. Among these may be mentioned the ladybugs, which 

 feed on plant lice and scale insects. The Chinese ladybugs and 

 the Australian ladybug have been used largely in California to 



