TREATMENT. 



Where this insect is abundant, treatment for it is necessary if the 

 elms are to be preserved. Generally speaking, a tree will suffer 

 defoliation once or even twice without being killed, but if defoliated 

 three times in succession serious injury at least, if not death, must 

 be the result. 



Spraying is undoubtedly the best way to check the attacks of the 

 elm leaf-beetle, and the cost is much less than might be supposed. 

 The spraying should be done first when the leaves are partly grown 

 in spring, as at this time the beetles which have wintered over feed 

 on the leaves for some time before laying their eggs as well as during 

 the intervals between the deposition of the different clusters. This 

 treatment will destroy many, at least, of the beetles, which would 

 otherwise produce young to do damage later in the season. 



A second spraying will often be necessary however, soon after 

 the eggs hatch, and as the young grubs feed on the under side of the 

 leaves, not eating the upper surface, the aim should be to spray so 

 that the poison may reach the under surface of the leaves as far as 

 possible. 



If these treatments have been neglected, or for any reason have 

 proved inefficient, the insects may be attacked while on the trunk 

 and ground where they are more accessible than when scattered 

 over the tree. At this time however, the damage has already been 

 done and by destroying the insects at this time only the size of the 

 following brood will be reduced. Still, this is well worth doing with 

 a view to protecting the trees from another attack while still in a 

 weakened condition. 



For the same reason the destruction of all the beetles found in 

 hiding during the winter, is extremely desirable. 



In spraying the trees Paris green or arsenate of lead may be used, 

 the latter being preferable as it does not burn the leaves at any 

 strength when properly prepared. For destroying the insects on the 

 trunk and ground boiling water is excellent, but as it is often impos- 

 sible to get it to the trees sufficiently hot, kerosene emulsion or the 

 mechanical mixture of kerosene and water may be found more con- 

 venient for use. 



