THE MONTHLY BULLETIN. 231 



THE HOP FLEA BEETLE. 



Psylliodes punctulata Melsh. (Family Chrysomelidse). 

 General Appearance. — A very small, black metallic beetle with 

 greenish tinge; oval in form; one tenth of an inch long and half as 

 wide. The eggs are very small, oval in shape and yellow. The larvse 

 are small white grnbs abont 5 mm. long. The white pupa3 as well as 

 the larvffi are found in the soil. 



Life History. — The adults appear early in the spring and are ready 

 to attack the first hop plants as soon as they come through the ground. 

 They feed upon the upper surfaces of the leaves, completely skeletoniz- 

 ing them. The vines are attacked when young and are often com- 

 pletely destroyed before they have reached a heighth of three or four 

 feet. When disturbed the beetles hop or fall to the ground. They 

 are able to make their way through the soil without much difficulty 

 and lay their eggs upon the roots of the food plants. 



The larvEe are very small and white in color with dusky markings. 

 They live in the ground feeding upon the roots of various plants. 

 When full grown they pupate in the soil from which the adults emerge 

 throughout nearly the entire year, the largest number appearing from 

 early spring to August. There are probably tw^o generations a year. 



Distribution. — Generally throughout the entire State. In the Sac- 

 ramento Valley considerable damage is done to hops by this pest. It 

 is also common in the beet fields of the southern part of the State. 



Food Plants. — This species feeds upon hops, cabbage, potatoes, beets, 

 turnips, dock, lambsquarters, pigweed, clover, rhubarb, cucumber, 

 radish, mustard and nettle. 



Control. — There have been numerous methods of control recom- 

 mended for this pest. The measures directed against the hibernating 

 beetles consist in killing all on the poles or burning up the rubbish. 

 In the spring the first step consists in capturing the adult beetles on 

 the young vines. A tarred board or hand hopper-dozer is used on or 

 into which the beetles are shaken. Tanglefoot bands around the bases 

 of the tresseled vines, as well as around the poles, not only keep the 

 beetles from the foliage but capture great quantities of them. Various 

 contract sprays, such as tobacco extract, emulsions, soaps, resin wash, 

 and arsenic also have been used with good effect, but the cost due to 

 great numbers of applications necessary, makes them almost prohibitive. 



