12 CONNECTICUT EXPERIMENT STATION BULLETIN I55. 



Destroying the pupae. 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 quantites; 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 

 they become very active in spring and dropping them into the 

 fire, hot water or kerosene to kill them. 



OUTFIT FOE SPRAYING ELM TREES. 



The barrel hand-power pump can be used for spraying small 

 trees or for a limited number of large trees, but if one expects 

 to make a business of spraying street trees, it will pay to pro- 

 cure a power sprayer; this may be a steam or gasoline engine 

 with pump, or what is perhaps better, the "Niagara Gas 

 Sprayer," which utilizes cylinders of carbonic acid gas to 

 furnish pressure, thus doing away with a pump. Each large 

 village and city should have at least one power sprayer that can 

 be put to immediate use for spraying street or park trees. 

 Strong one-half inch hose should be provided in long lines of 

 from fifty to two hundred feet, and from four to six of these 

 can be attached to each power sprayer. Even a larger number 

 might be attached, but while in operation some workmen would 

 be in the way of others, so that nothing would be gained. Mr. 

 H. L. Frost of Boston, who is in the spraying business, 

 informed the writer that four lines of hose is about the most 

 economical number for each outfit. Each hose is furnished 

 with an extension rod with closing valve at the lower end 



