824 CONNECTICUT EXPERIMENT STATION REPORT, I907-I908. 



(2) The other method is to spray the under sides of the leaves 

 very thoroughly about June ist, or soon after the eggs begin to 

 hatch. This treatment is aimed at the larvae, and sometimes a 

 single spraying is sufficient, as the poison will remain throughout 

 the season. By it the great bulk of damage will be prevented, but 

 the leaves will show the small holes made by the parent beetles 

 before the poison was applied. 



If arsenate of lead cannot be procured and it seems desirable 

 to use other poisons, Paris green can be substituted. 



This should be used at the following rate : 



{ 



Paris Green I lb. 



Formula \ Fresh lime 3 lbs. 



Water 5° gals. 



Paris green is quicker in its action upon the insects than arsen- 

 ate of lead, but will not remain as long upon the trees. Unless the 

 lime is added, there is danger of "burning" the leaves. Lime 

 is not needed with arsenate of lead. 



The cost of spraying elm trees will vary from ten cents 

 each in case of small trees to five dollars or more for the largest 

 trees, according to the price of labor and the efficiency of the 

 outfit. 



Destroying the pupcB. If the trees have not been protected 

 by spraying, and have been attacked and injured by a horde 

 of beetles and their larvae, it is always advisable to destroy the 

 insects in the pupa stage at the base of the trees, in order to 

 reduce the crop for next year as much as possible. These can 

 often be swept up in large quantities; they can be killed by 

 sprinkling them with hot water; but best of all is to spray the 

 ground not only close to the tree but as far away as the branches 

 reach, and also spray the bark of the trunk and large branches, 

 with kerosene emulsion or some other contact insecticide. The 

 pupae are easy to kill, but as they remain in the pupa stage only 

 about ten days, it is essential that this work be done at the right 

 time, and it is only when we observe that most of the larvae 

 descending the trunk have transformed to bright yellow pupae 

 that we can know when is the proper time to act. 



Destroying the adult beetles. The beetles should of course 

 be destroyed in attics, belfries and other places where they 

 hibernate. This can best be done by sweeping them up before 



