EXPERIMENT STATION BULLETINS. 



263 



REMEDIES. 



Most saw-flies are comparatively easy to kill if it possible to get at them. In this 

 case the larvae readily sucevuiih to most of the poisons, but unfortunately thej' come out 

 (luring the time when the fruit is on the canes and it is impossible to use arsenicals. 

 Dr. Saunders recommends hellebore apjdied in the form of a spray, using one ounce 

 to a pailful of water. This can be used on the plants early in the season if the fruit 

 is just set, but after the fruit" is well set it is unsafe. A good spray of kerosene 

 emulsion has been found very useful, but in using this it must be remembered that 

 each worm must be hit to be killed, and the ])lants are not protected against the great 

 luimbers that constantly are being hatched from the eggs. These will require a repe- 

 tition of the treatment, sometimes several repetitions. A strong solution of soft soap 

 has been \ised successful!}' when applied very thoroughly. 



CARPENTER HEES. 



While examining the fields of red raspberries infested with the saw-fly. many of the 

 canes, cut oft" the year before, were found to have tunnels in the pith for a distance 

 of from one to six inches. These round timnels were about one-eighth of an inch 

 in diameter and very smooth and even. One was split down the side with a penknife 

 and found to be tunneled by a small wasp {Xylocrahro siirpicola) . Pack.* one of the 

 adults emerging as the cane was cut. Another species (Ceratina dupla) , Say,* was 

 bred from the tunneled stems. Fig. 15. The life history of these insects is verj* inter- 



Fig. l.';. Tunnels of Carpenter-bees in Red-raspberry. ^Original.) 



esting. The mother cuts out one of these holes, and after storing food in it. lays an 

 e^^, and then places a partition over food and egg. making a small room. This 

 process is repeated, making a series of chambers or si)aces, each with its c^g and 

 stored food. The eggs hatch and the young grubs feed on the stored food, in time 

 spinning cocoons and turning into winged wasp-like insects themselves. 



• These two insects were kindlv determined for me by Mr. Asbmead through the kindness of Br. L. 

 O. Howard of the Department of Agriculture, Washington, D. C. 



