8 



MISC. PUBLICATION 626, U. S. DEPT. OF- AGRICULTURE 



others are dark gray or gray spotted 

 with black. The larvae, or grubs, live 

 in the soil, but are not destructive to 

 vegetation. They usually feed on egg 

 masses of grasshoppers and crickets. 

 The most common form is the black 

 blister beetle (Epicauta pennsylvanica 

 (Deg.)) (fig. 14, p. 8), sometimes called 

 the aster bug because it is so destructive 

 to asters. Other species are the striped 

 blister beetle (Epicauta vittata (F.)) and 

 the grav blister beetle (Epicauta cinerea 

 ^Forst.)). 



under side, giving the leaves a shot-hole 

 appearance. At times, however, they 

 eat only through the upper epidermis 

 (fig. 15, B). The beetles are especially 

 injurious to young seedlings. These 

 insects derive their name from the fact 

 that when disturbed they jump away 

 in a manner resembling fleas, and they 



Figure 14. — Adult of the black blister 

 beetle. About V/2 times natural size. 



Treatment. — Blister beetles are diffi- 

 cult to control because they are so active 

 that they are not easily covered with 

 contact insecticides. Spraying with a 

 combination of derris powder and py- 

 rethrum extract (p. 99) kills such beetles 

 as are actually hit by the spray. Arseni- 

 cal sprays or dusts will repel the beetles 

 and poison some of them. Dusting or 

 spraying the plants with barium fluosili- 

 cate or cryolite (p. 97) is also useful. 

 Where only a few plants are infested, 

 hand picking often suffices, but gloves 

 should be worn because contact with 

 the beetles may blister tender skin. 

 Knocking the beetles into a container 

 holding a small quantity of water upon 

 which kerosene or other oil has been 

 poured is another means of killing them. 



Prevention. — Valuable plants may 

 be protected by covering them with 

 cheesecloth or fine wire screen. 



FLEA BEETLES 



Flea beetles are general feeders and 

 are frequently found on the foliage of 

 flower-garden plants, where they gnaw 

 small holes through the leaves from the 



Figure 15. — A, Adult of the striped 

 flea beetle, about 3 times natural 

 size; B, holes eaten in the surface of 

 a wallflower leaf b}^ the striped flea 

 beetle, natural size. 



