INJURIOUS AND BENEFICIAL INSECTS OF CALIFORNIA. 



239 



Nature of Work. — The work of the adults only has proved serious. 

 The beetles burrow into the branches and small twigs, usually in a 

 fork or axil. The burrows or tunnels are round, from i to | inch in 

 diameter and seldom more than an inch long, in living tissues. They 

 are large enough, however, to weaken or almost completely sever the 

 twigs. Small trees suffer most by the pruning thus received. 



Distribution. — The branch and twig-borer is generally distributed 

 throughout the State. 



Food Plants. — The plants attacked are acacia, almond, apple, apri- 

 cot, cherry, currant, fig, grape, coast live oak, maul oak, olive, orange, 

 peach, pear and -prune. 



Control. — Control measures are very difficult and from a financial 

 point of view are. out of the question, as the damage done would not 

 warrant the cost of adequate remedies. 



THE TRICOLORED XYLOPERTHA 



Xylopertha saturate (Horn) 142 (Family Bostrychidae) 



( siiiiu-i/loii suturale Horn) 

 (Fig. 228) 



Description. — The beetles are nearly cylindrical in shape, about £ 

 inch long; head and abdomen, black; prothorax and posterior half of 

 wing covers, dark red- 

 dish-brown, and the an- 

 tennas, legs and anterior 

 half of the wins covers, 

 light amber. 



Life History. — The 

 adults bore into the canes 

 and smaller twigs. The 

 larva? also work within 

 the same hosts and pupate 

 in the burrows. Adults 

 usually continue in their 

 tunnels during the winter 

 and issue early in the 

 spring. 



Nature of Work. The 

 larva? work near the 

 center of grapevine canes 

 and just beneath the bark 

 in the twigs of trees. The adults make their burrows, which are about 

 the size of the lead in a pencil, around the twigs, just under the bark. 

 The small, round entrance and exit holes give evidence of the presence 

 of the beetle. 



Distribution. — This species was collected in San Diego County, 

 February, 1914, by Mr. H. A. Weinland. It has been recorded in Los 

 Angeles County by D. W. Coquillett 143 and H. C. Fall 144 and in Santa 



,4 -A uniformly brown species. Xylopertha declive (Lee), is more abundant than 

 the above. It attacks acacia, California laurel, eucalyptus and oak. Tt also bores 

 through the lead casings of telephone wires. 



'"Insect Life IV, p. 261, 1892. 



^Cal. Acad. Sci. VIII, p. 133, 1901. 



Fig. 228. — The tricolored Xylopertha, Xylopertha 

 suturale (Horn). Beetles and their work on acacia. 

 Slightly enlarged. Specimens collected at San Diego 

 by H. A. Weinland. (Original) 



