INJURIOUS TO CABBAGE AND RELATED CROPS 11 



Fig. 12. 



Moth of the cabbage looper (X 1^). 



by a disease. Diseased cater})illars at first turn yellowish and 

 later take on an ashy hue (Fi^. 13). They become inactive, 

 stop feeding and soon die. After death the skin breaks open 

 and the body contents 

 which have become 

 liquid oozes out and 

 becomes smeared on 

 the leaves. Sometimes 

 a large proportion of 

 the caterpillars are de- 

 stroyed by this disease 

 late in the season. 



Control. 



The cabbage looper 

 is a difficult insect to 

 poison because the caterpillars refuse to eat leaves coated 

 with an insecticide and move quickly to some part of the 

 plant that has been missed in spraying. Furthermore, it is 

 not easy to spray a cabbage plant so as to cover all parts 



of the leaves, especially the 

 underside of the outer leaves 

 and those in the forming 

 head. Experiments on Long 

 Island have shown that good 

 results may be obtained by 

 thorough spraying with paris 

 green, 1 pound in 80 gallons 

 of water to which the resin- 

 lime mixture has been added. Some growers dust the plants 

 lightly with pure paris green and have reported satisfactory 

 results from this treatment. 



Fig. 13. — A diseased cabbage looper 

 (X li). 



