428 



INJURIOUS AND BENEFICIAL INSECTS OF CALIFORNIA. 



Nature of Work. — The larvae make their burrows down the pith of 

 the stems, which are eventually killed. The dead twigs, the tunnels 

 filled with frass and the exit holes of the adults are characteristic signs 

 of the presence of this pest. 



Distribution. — The imported currant borer is limited to the northern 

 and central parts of the State, and more particularly to the Sierra 

 foothill regions. 



Food Plants. — The young caterpillars work on the pith within the 

 stalks or canes of the currant and gooseberry, doing much damage to 

 the fruit-bearing wood. In not a few cases entire patches have been 



Pig. 4 36. — Pupal skins of the imported currant borer. 

 .ISgeria tipuliformis Clerck, at the exit holes of the burrows. 

 Enlarged twice. (Author's illustration, Mo. Bui. Cal. Hort. 

 Com.) 



rendered worthless before the unsuspecting grower was aware of the 

 real cause of the dying bushes. Currant, black elder, red and black 

 gooseberry, hazelnut and sumach are recorded as hosts in Europe. 299 



Control. — Control is rather difficult and consists in cutting out and 

 burning the sickly-looking canes as often as they appear. The best 

 time to do this work is in the spring. If living canes are infested, the 

 larva 1 may sometimes lie killed by thrusting a wire down the burrow. 



29!, Rev. Appld. Ent. I, p. 68, 1913, 



