FLEA-BEETLES 



335 



Reference 

 U. S. Dept. Agr. Bull. 43G. 1917. 



The Hop Flea-Beetle 



Psylliodes punctulata Melsheimer 



Although this flea-beetle is best known as a destructive 

 enemy of hops in the Northwest, it is widely distributed 

 throughout the northern United States and southern Canada 

 from the Atlantic to the Pacific and also attacks several garden 

 plants, including beet, rhubarb, potato, tomato, turnip, radish, 

 cabbage, cucumber, watermelon, mustard and clover. Its 

 wild food plants are numerous, including 

 hedge mustard, lamb's quarters, pigweed, 

 dock, sorrel, tumbleweed and nettle. 



The hop flea-beetle is about ^o" i^^^h in 

 length and bronzy black in color. The 

 antennae are brownish, pale at the base. 

 The legs are reddish yellow with the middle 

 and front femora black and the hind pair 

 bronzy (Fig. 212). The beetles hibernate 

 under any convenient shelter, such as cracks 

 and crevices of posts or poles, in the hollow 

 stems of plants, under grass or weeds, and in the soil itself. 

 In British Columbia they emerge in March or April and soon 

 begin feeding on the foliage of their food plants, eating out 

 pits, but usually do not perforate the leaf. The injured area 

 soon dries, however, and may break away, leaving a hole 

 through the leaf. The foliage is often riddled in this way and 

 in the case of hops the leaves are reduced to mere shreds. 



The females enter the soil to lay their eggs on the roots of 

 the hop. The egg is about rt inch long, elliptico-cylindrical, 

 and yellowish in color. They are found at a depth of one to 



Fig. 212. —The hop 

 flea-beetle (X 10). 



