280 [NJURIOUS AND BENEFICIAL INSECTS OP CALIFORNIA. 



Nature of Work. — Tin 1 beetles feed upon the leaves, leaving only 

 portions of stems after them. 



Distribution. — Tli is species appears to be limited to the southern 

 pari of the Slate and more particularly to the hotter southeastern 

 portions, extending into Arizona and Mexico. 



Food Plants. — The native food plants are not recorded. Dining 

 April and the first of May, 1914, the State University reported a field 

 of cotton greatly injured by its attacks. 



Control. — The application of poison sprays composed of 4 pounds 

 of neutral arsenate of lead to 50 gallons of water is recommended, 

 though it is doubtful if control measures will ever be necessary except 

 in extreme cases. 



THE HOP FLEA-BEETLE 



PsyUiodex punctulata Melsheimer 



(Fig. 273) 



Description. — The beetles are small, metallic black or green, oval, 

 i 1 ( t inch long and half as wide. The eggs are very small, oval, and 

 yellow. The grubs are white, with dusky markings, slender, and about 

 1% inch long. The pupae are white and about the size of the adults. 



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 skeletonizing 

 them. The vines are often entirely 

 destroyed before they have reached a 

 height 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 dif- 

 ficulty and lay their eggs upon the 

 roots of the food plants. 



The larvae live in the ground, feeding 



Psy}I' d" 3 'wSato Meifh a AduitS u P on the roots of various plants. When 



enlarged twice. (Original) 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 two generations a year. 



Nature of Work. — The larva' work upon the roots and do little 

 damage, while the adults work upon the leaves of hops and sometimes 

 cause very serious losses. They eat small holes in the leaves similar to 

 those made by other flea-beetles. 



Distribution. — This beetle appears to be quite widely distributed 

 throughout the Slate, but so far has not proven to be a serious pest. 



Food Plants. — The following plants are attacked: beet (garden and 

 sugar), cabbage, clover, cucumber, dock, hop, lambsquarters, mustard, 

 nettle, potato, radish, rhubarb, sorrel, tomato and turnip. W. B. 

 Parker, who has done much work on hop insects during the past few 

 years in California, states that this beetle is not a hop pest in this State. 



