406 



INSECT PESTS OF FARM, GARDEN AND ORCHARD 



Life History. The beetles appear in early summer and the 

 females girdle the young tips by cutting two rings around the 

 shoot about an inch apart, causing the tip to wither and droop. 

 Between these rings will be found a small dark spot where the 

 female has inserted an egg in the cane. A rather large, elliptical, 

 yellow egg is placed in the pith of the cane and in a few days 

 hatches into a small white grub. The larvse burrow downward 

 through the pith of the stems, the burrows winding from side 

 to side and frequently penetrating the side of the stem, where 

 openings are made every few inches, through which long strings 



FIG. 339. The raspberry cane-borer (Oberea bimaculata .Oliv.) : adult, larva, 

 and larval castings all enlarged. (After Lugger.) 



of excrement are cast out. By fall they are bored to the base 

 of the cane, in which they hibernate over winter. The full- 

 grown larva is about one inch long, of a dull yellow color, with 

 a small dark-brown head. The body is quite cylindrical and 

 the segments constricted as shown in Fig. 339. The pupal stage is 

 passed in the burrow during the spring. Although it has been 

 generally assumed that the life cycle is passed in a single year, there 

 is some reason for believing that two years may be required. The 

 eggs are usually laid only in the young tips, but Comstock and 

 Slingerland found larvse somewhat over half grown which had 

 made burrows only two inches long in old canes in late July, and 

 Professor Webster has secured larvse over half grown in early 



