252 



INJURIOl'S AND BENEFICIAL INSECTS OF CALIFORNIA. 



finding the burrows in the trunks, but only the dying tree will disclose 

 the injury to the roots. Pupation takes place in early summer. 



Nature of Work.™ The larvae destroy the roots by completely hol- 

 lowing them out. They also make large burrows in the trunks, from 

 which the sap may or may not flow. Young trees are often completely 

 killed by their attacks. 



Fil 



!41, — The California Prionus, Prionus californicua Mots. Adults 

 enlarged twice. (Original) 



Distribution. — This species is widely distributed throughout the 

 Slate and is exceedingly common. 



Food Plants. — The following plants are attacked: apple, black- 

 berry, chestnut, grape, oak, poplar, prune and black and English 

 walnut. 



Control.— Probably the best method is to dig out the larvae or kill 

 I hem in the burrows with a wire. Control measures, however, are sel- 

 dom if ever necessary for this beetle. 



THE SPOTTED TREE-BORER 

 Synaphoeta guewi Leeonte 



(Fig. 242.) 



Description. — The beetles are bluish-gray with black markings and 

 spots, as shown in Fig. 242. The dorsum, especially around the mar- 

 gins of the black areas, are marked with orange-yellow. The antennae 

 r.re longer than the body and the bases of all the joints except the first 

 two are light blue. The legs are marked with light blue and black 

 and spotted with orange and black. The inside of the first three tarsi 



