ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 



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Fig. 10. — Yellow-necked caterpillar: larvae on small branch of haw- 

 thorn. When disturbed, these caterpillars rear up at both ends. Reddish 

 when young, each caterpillar has a black head and four yellow stripes along 

 each side of its body. A grown caterpillar is easily recognized by its yellow 

 neck and its black body, which is covered with long, white hairs. 



Fig. 11. — Woolly hawthorn aphid: infestation on hawthorn twig, 

 aphids, which are white in color, have sucking mouthparts. 



The 



