INSECT ENEMIES. 99 



1. Catch the butterflies with a net when they 

 first appear in spring, before they have laid their 

 eggs. This may keep the insect in check for a 

 year or two when it first makes its appearance, as 

 the butterflies are comparatively slow fliers, and 

 may be caught without much difficulty by a spry 

 boy, especially in the morning when the air is 

 damp. 



2. Early in the season keep the young plants 

 excluded from the butterflies, and the whole place 

 free from everything else of the cabbage tribe, 

 except one or more patches of rutabagas or rape, 

 on which the butterflies will lay their eggs. This 

 piece is to be then plowed under. 



3. Hand pick the worms from the plants after 

 they are set out, for the first one or two hoeings, 

 or until the worms become very numerous. 



4. Spray with kerosene emulsion, made by using 

 two gallons of kerosene, one-half pound of common 

 or whale oil soap, and one gallon of water. Dis- 

 solve the soap in the water, and add it, boiling hot, 

 to the kerosene; then churn, while at least warm, 

 for five or ten minutes, by means of a force pump 

 and spraying nozzle, until the mixture loses its 

 oiliness and becomes like butter. When used, 

 dilute one part of the emulsion with about fifteen 

 of water, and spray it upon the plants by means of 

 a force pump and spraying nozzle. This emulsion 



