INSECTS THAT INJUEE CROPS 



of combating insects as well as plant diseases. There 

 is much to learn about insects before we can hope to 

 control them successfully. We must learn when and 

 where the insects lay their eggs, when the eggs hatch, 

 and into what forms they develop, and what they feed 

 upon. Some people make fun of boys and girls when 

 they see them hunting and studying "bugs," but if 

 somebody did not hunt and study bugs, they would 

 eat and drive us all out of house and home. 



Life history of an insect. There are usually four 

 stages in the life history of an insect the egg stage, 

 the grub or caterpil- 

 lar stage, the resting 

 or pupa stage, and 

 the full-grown insect. 

 The egg is laid by 

 the full-grown insect 

 in the ground or in 

 any part of the plant. 

 The eggs hatch into 

 what we usually call 

 a grub or worm. The 

 grub of most insects 

 is a great eater, and it is in this stage that much dam- 

 age is done to our plants. After it has eaten and grown 

 fat, it hides itself and goes into a pupa or resting stage. 

 From this pod-like affair it emerges as a full-grown in- 

 sect, ready to lay eggs and repeat the life cycle. Some in- 

 sects, such as grasshoppers, do not go into the resting 



SHOWING GYPSY MOTH LARVAE 

 ASCENDING 



