THE PEACH SAWFLY. 299 



It is impossible to predict with any certainty regarding this 

 new pest. The sawfly promises to become distributed through- 

 out the state, as it has been found in New Haven arijd Middlesex 

 counties at points nearly thirty miles apart; but whether it will 

 become numerous enough to cause serious injury depends largely 

 upon the rapidity with which it multiplies, and the part that 

 natural enemies may take in reducing its number. From our 

 observations, the numbers are not greatly increased during a 

 single season, and it would seem that the pest would necessarily 

 have to be present in an orchard several seasons before it would 

 do extensive damage. The larvae are very easily killed by 

 arsenical poisons, and it is quite possible that one application may 

 reduce their numbers sufficiently so that the operation would 

 not have to be repeated for two or three years. It will be 

 necessary to study the insect for a number of seasons before 

 we can judge regarding the seriousness of the new pest that 

 has been found in our state. 



Acknowledgments. 



The writer is indebted to Dr. Britton, under whose direction 

 the work has been done, for much help and many suggestions. 



To Barnes Brothers, who placed their orchard at our disposal, 

 furnished lumber for breeding cages, and assisted the work in 

 many ways. 



To Mr. George A. Hopson and Mr. Charles E. Lyman, who 

 spent considerable time at a very busy season, conducting the 

 writer through their orchards. 



Recommendations. 



From our experience we recommend spraying the foliage 

 with arsenate of lead, using it at the rate of one and one-half to 

 three pounds in forty to fifty gallons of water. This should, be 

 applied as soon as the larvae begin to hatch, or if a large area 

 is to be sprayed with a limited amount of help, the work could 

 probably be started shortly after the eggs are laid. The exact 

 date will depend, of course, upon the season ; this was found to 

 vary about two weeks during the past two seasons. The point 

 is, the larval stage is short and the work must be done quickly 

 . at the proper time, and in order to determine this a close watch 

 must be kept of the progress of the development of the insect. 



