34 THE MONTHLY BULLETIN. 



their way into the young cherry and work upon the tender kernels 

 where they feed from two to four days or until the fruits are eaten out 

 or withered. They then seek new cherries and repeat the same process, 

 though the time required to destroy the second is about twice that 

 of the first. The third cherry is usually also destroyed by each larva, 

 but in this case the kernel is too hard to be eaten so that only the portions 

 around it are consumed, which often includes nearly or over half of the 

 fruit. There is little evidence of the attack upon the first cherries but 

 the entrance holes are plainly seen in the second and third series. 



The writer is not aware if these records hold true with regard to the 

 work on the prune, plum and other hosts or not, the complete life 

 history not having been recorded in the localities where these fruits 

 are attacked. The larvae reach maturity in from twenty-two to twenty- 

 six days and are then yellowish-Avhite with head, tip of abdomen and 

 legs darker yellow, and eyes ])lack. They have three pairs of well 

 developed legs near the head, six pairs. of small prolegs back of these 

 and one pair of larger prolegs at the posterior end of the body. The 

 body is usually curved almost to the shape of a letter " C " and is very 

 plainly wrinkled (Figs. 3 and 4, c). 



As soon as full grown the larvas leave the fruit and enter the ground 

 to a depth of from three to seven inches for pupation. The pups are 

 dark brown and are enclosed in thin cocoons which are oval in shape 

 and from three eighths to one fourth of an inch in length. The pupae 

 remain in the ground until spring and the adults emerge in March to 

 begin egg laying as soon as the M^ell formed blossom buds appear. 



The adults are mostly l)lack with light reddish brown or yellowish ' 

 appendages. A portion of the head is also reddish. The females meas- 

 ure 3.5 mm. while the males are 3 mm. in length. They have four well 

 developed wings, as shown by the illustration of the female (Fig. 4, d). 



Control. 



Mr. P. J. O'Gara has had more experience in the control of this 

 insect than any other person. In reply to a communication addressed 

 him relative to the control of this pest he writes ■} 



'•Regarding the matter of the control of the cherry fruit sawfly, 

 Hoplocampa cool'ei, I may say that "we have used both the tri- 

 plumbic and Pyro arsenates of lead. Of course, the tri-plumbic 

 lead is much safer under moist climatic conditions, but, so far, we 

 have seen no injury resulting from good Pyro lead. 



I have been working on the control of this insect for the past 

 three seasons and find that to fully control it from two to three 

 applications of lead arsenate at the rate of 4 to 5 pounds of arsenate 

 of lead to 100 gallons of water may be necessary. However, as a 

 rule, two good applications have been sufficient. The first applica- 

 tion should be made shortly before the blossoms of the cherry or 

 related fruits open; the second about ten days later, or when the 

 petals have mostly fallen. If a third spray must be applied, it 

 should come just after the shucks have fallen. Because of the fact 

 that a single larva may destroy from three to four fruits, it is 

 evident that Avith proper spraying the insect may be prevented 



iMedford, Oregon, May IS, 1913. 



