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injure trees both in their immature and mature stages. 

 The adults are hard-bodied insects, well known under 

 such names as June-bug and potato-bug, while their young 

 are known as grubs, those attacking trees having well 

 developed heads but often no legs. Their bodies are gen- 

 erally thick and stout, and are more or less U-shaped in 

 many cases. They attack roots, trunk and leaves. 



True Bugs (Order Hemiptera). A large number of 

 this group of insects attack the foliage and tender 

 growths of twigs, and a few such species as tlie 17-year 

 locust (cicada) suck the sap from the roots of trees. All 

 such insects are provided with a piercing proboscis, and 

 feed at all stages of their growth upon the sap of plants . 

 The order includes, besides the 17-year locust, such spe- 

 cies as the plant-lice (aphides), the bark-lice, the various 

 tree-and leaf-hoppers, and the plant-bugs (Capsidse) the 

 latter sometimes very destructive to young fruit trees. 



Sawflies and Bees (Order Hymenoptera). In the grub 

 state some of these insects gnaw away the leaves of trees 

 and other plants, while other small species gall the twigs 

 and leaves. The sawflies, including the elm sawfly, the 

 currant-worm, and the like, are our most destructive 

 species. The adults do little mischief of any sort, and 

 many species are beneficial by helping to fertilize flowers 

 of useful plants. 



Flies (Order Diptera). In their adult state these are 

 two-winged insects such as the housefly, mosquito, and 

 buffalo-gnat. When not matura they are known as 

 grubs, maggots and wrigglers. Though sometimes very 

 annoying to man and the domestic animals, the winged 

 adults do no harm to vegetation. The grubs of a few 

 small flies and gnats live in galls or mines in the leaves 

 and twigs of trees, while a few others mine seed-pods, 

 and other kinds of fruit. The grubs may be known from 



