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INSECTS INJURIOUS TO VEGETABLES 



is soon exhausted, the tips and leaves wilt and its death fol- 

 lows. It is not alone the extraction of the juices that destroys 

 a plant;, whenever the bug "stings" a leaf-stalk, it injects a 

 liquid, which has a poisonous effect, causing the death of the 

 cell tissue about the puncture. It attacks also the leaves and 

 occasionally the fruit, and acts as a transmitter of the "wilt." 



d e 



Fig. 108.— Squash bug. a. Adult; b, egg mass; c, d, e, nymphal stages. Enlarged 

 (Author's illustration, U.S. Dept. Agr.) 



On young plants a few punctures are sometimes sufficient 

 to cause death. 



The common squash bug is known throughout practically 

 the entire United States, being particularly abundant east of 

 the Rocky Mountains, where it ranges from Maine to the 

 Gulf States and westward to California. 



Injury may begin soon after the sprouting of the plants, or 

 after they have made considerable growth, and may continue 

 until their death or the departure of the bugs for hibernation. 

 Plants are first attacked by the hibernated bugs. Soon after 

 their appearance, which varies according to temperature and 

 locality from early spring in the South to late in June farther 



