INSECTS INJURIOUS TO RASPBERRY AND BLACKBERRY 411 



The Blackberry Gall-maker * 



The so-called " pithy gall" of the blackberry is an elongated, 

 pithy swelling from one to three inches long and nearly an inch 

 in diameter, red or reddish-brown, with the surface divided by 

 deep longitudinal furrows into four or five ridges or parts. The 

 gall is caused by the larvae 

 of a small black gall-fly, 

 which is about one-twelfth 

 inch long, with red feet 

 and antennae and four 

 transparent wings, almost 

 lacking wing-veins. The 

 insect passes the winter in 

 the larval stage in the galls, 

 and if one be opened at 

 that season, there will be / 

 found about the middle a 

 number of cells about one- 

 eighth inch long, each of 

 which contains a single 

 larva. The larva " i s 

 about one-tenth inch long, 

 white, with the mouth- 

 parts reddish, and the 

 breathing pores and an oval 

 spot on each side behind 

 the head of the same color." 

 They change to pupae in 



spring and the flies appear FlG - 346 - T1 ? e pithy-gall of the blackberry: a, 

 i;j.j.i i i rpi i gall; 6, section of same showing larvae in cells: 



a little later. Though c , larva enlarged and natural size; d, pupa, 

 this gall is also very com- (After Riley.) 



mon on wild canes it rarely does much injury. 



Control. The affected canes should be cut and burned during 

 the winter. 



The Raspberry-cane Maggot f 



The tips of young raspberry shoots sometimes droop and wilt 

 in the spring in much the same manner as when affected by the 



* Diastrophus turgidus Bass. Family Cynipida>. 



^Phorbia ruUvora Coquillet. Family Anthomyidce. See Slingerland, 



?o Ul in u 12 A 6 ' C T ne11 Univ ' A & r - Ex P" Sta "> P- 54 >' W - H - Lawrence, Bulletin 

 62, Wash. Agr. Exp. Sta. 



