COLE CROP PROJECTS 



105 



surface of the leaf, and from these hatch small, green caterpillars 

 that immediately begin skeletonizing the leaf. In ten to fourteen 



Fig. 30. — Cabbage worm. 



days they become full grown and fasten themselves to the under 

 side of the leaf or other protected surface and change to a pupa 

 from which in about a week the butterfly emerges. Several broods 

 develop in a season. 



This pest is controlled by hand picking or dusting when only a 

 few plants are grown. Poison sprays applied as soon as young 

 caterpillars appear are the best for large plantings. 



1. What indicates maggot injury to cabbage f CL : 29-36. 



2. What is the life history of the maggot? CL : 29-30. 



3. Is clean farming a desirable practice? If so, why? CL:32. 



4. State briefly three methods of preventing injury by the maggot, 



indicating when each is mast desirable. CL : 33-36. 



