128 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. 



plowed, as already described, beyond the infested portion to check their 

 further spread. If these measures are undertaken promptly, what 

 might be a serious loss can be averted. 



FLEA BEETLES. 



(Haltica sps.) 



These beetles have generally been confused with the root beetle 

 already discussed in this bulletin. In these beetles the thighs of the 

 hind legs are enlarged, thus enabling the insect to jump much in the 

 same way as the flea; hence the name. They have frequently been 

 reported as doing damage in the State, but during the past season we 

 have not learned of any important injury done by them. Two or three 

 specimens were taken near Lodi, and while no particular effort was 

 made to collect them, this was all we obtained during the season. 

 Certainly there were no large numbers of these beetles in the sections 

 where our work was carried on this past year. Several growers reported 

 that the flea beetle was doing considerable damage, but upon investi- 

 gation these were found to be the root beetle. They are said to be 

 particularly abundant in the Sonoma Valley, but we did not have the 

 opportunity of visiting the valley during the present season. There 

 are about a dozen species of the genus Haltica occurring in this State, 

 probably the commonest occurring on the vine being the species bimar- 

 ginata. This species is not confined to the grape alone, and during the 

 past year it was exceedingly abundant in many places over the State 

 "on the alder. The grape flea beetle of the Eastern States (Haltica 

 chalybia) is not known to occur here. 



The flea beetle on the grape is commonly of a bluish color, about one- 

 fifth of an inch in length, and is capable of jumping, while the root 

 beetle is either black or brown in color and has no power to jump. The 

 injuries of these two beetles are also readily distinguishable. The flea 

 beetle eats out irregular holes, which may differ much in size and shape, 

 while the root beetle eats out narrow strips of very uniform size and 

 shape. They also present entirely different life histories. 



Life History. The flea beetle passes the winter among leaves or in 

 other situations affording some protection to the adult beetle, and 

 emerges in the early spring and feeds upon the buds of the vine. These 

 may be entirely eaten away or the centers gouged out, thus destroying 

 the buds. After feeding for some time they begin depositing their 

 eggs, generally in the cracks in the bark or at the base of the buds. 

 The larvae, after hatching out, attack the leaves and eat out holes, as 

 already indicated. They continue to feed as larvse for three or four 



