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eastern part. A fight against these insects, while costly, is 

 much more economical than to allow the pests to multiply 

 and spread without restriction. There is a prospect that 

 the heavy expenditures for repressive work may be ma- 

 terially lightened in the near future. Our principal hope 

 in controlling these two pests economically, lies in the find- 

 ing of efficient natural enemies. You are doubtless aware 

 that the State of Massachusetts, in cooperation with the 

 T^ederal Department of Agriculture, has introduced large 

 numbers of parasites, not only from Europe but also from 

 Japan. This work is necessarily slow. Marked relief can 

 hardly be expected for a few years. Nevertheless, the in- 

 troduction and the dissemination of these parasites is un- 

 doubtedly the most important work that has ever been 

 undertaken in connection with the gypsy and the brown 

 tail moths. This undertaking is fundamental, since it is an 

 effort to right the balance of Nature disturbed when these 

 two pests were brought to our shores. The far-reaching re- 

 sults, if efficient parasites can be obtained, are apparent to 

 all. I wish to emphasize this most strongly and to state 

 that, in my opinion, this feature of the work should be main- 

 tained at all hazards, even though progress along these lines 

 may seem to be very slow. 



The elm leaf beetle is another European pest which has 

 become. well established in Massachusetts, and has been re- 

 sponsible for much injury. It can be controlled, like other 

 leaf feeders, by thorough and judicious applications of 

 poisons, the arsenate of lead being by all means preferable. 

 The secret in controlling this insect lies in throwing the 

 poison upon the under side of the leaves where the destruc- 

 tive grubs do all their feeding. This pest can also be 

 checked considerably by pouring boiling water over the 

 black and yellowish grubs of the golden yellow pupae, so 

 frequently seen in large numbers at the base of infested 

 trees. An incidental feature of the work with parasites of 

 the gypsy and brown tail moths, has been the introduction 

 of an egg parasite of the elm leaf beetle. It may be that 

 this little insect, introduced through the personal efforts 

 of Dr. L. O. Howard, Chief of the Bureau of Entymology, 

 may be a potent factor in reducing the destructiveness of this 

 beetle. 



