2f>4 



INJURIOUS AND BENEFICIAL INSECTS OF CALIFORNIA. 



Distribution. — The beetle occurs in the middle and northern Sierra 

 Mountains. 168 



Food Plants. — Cultivated gooseberry bushes have been recorded as 

 hosts, but as the insect is native no doubt wild gooseberry and probably 

 other related plants are also attacked. 



Control. — Cut out and burn the infested canes when the damage 

 is severe enough to warrant control measures. 



THE NAUTICAL BORER 



Xylotrechus nauticus Mannerheim 



(Figs. 244, 245) 



Description. — The beetles are slender with noticeably long legs 

 and rather short antennae. The color is dark with irregular light 

 broken bands on the elytra, as shown in Fig. 245. The body is entirely 

 covered with fine white hair, giving a decidedly grayish appearance. 

 The average length of the females is about \ inch. The males are 

 slightly smaller. The larvae are white with brown heads and mandibles. 

 The body is slightly larger near the head and | inch long. The pupae 

 are yellow or white and slightly over \ inch long. 



Fig. 244. — The nautical borer. Xyloterchus nauticus Mann. Larvae 

 in burrows in walnut twigs and exit hole near a bud. Natural size. 

 Specimens received from R. S. Vaile, Ventura. (Original) 



Life History.— The winter is passed in the larval stage within the 

 burrows, where pupation takes place in April and May. The adults 

 begin to issue the last of April. They are nocturnal and diurnal in 

 habits. There appears to be but one brood a year. 



Nature of Work.— The larva? usually burrow into the tips of the 

 branches, killing the twigs back for from one to several feet. They also 

 enter the trunks and larger branches, especially if a tree is at all sickly 



'"Fall, H. C, Pine. Cal. Ac-id. Sri., VIII, p. 144, 1901. 



