154 ^"E\V YORK STATE MUSEUM 



tobrochis grand is Uhler, sucks the eggs. Larvae of lacewing flies, 

 also called aphis lions, are frequently found on leaves with the young of the 

 elm leaf beetle, and are reported by Riley to feed on both eggs and larvae. 

 Mites have been observed by the writer near egg clusters that had suffered 

 injurv. This insect finds an enemy in the southern portion of its range in 

 the praying mantis, S t a g m o m a n t i s c a r o 1 i n a Linn. 1 1 is very prob- 

 able that the European praying mantis, Mantis r e 1 i g i o s a Linn., recently 

 established in a ninnber of localities in the state through the efforts of the 

 writer, will also prey on this injurious beetle. 



Remedial measures. The secret of controlling an insect frequeritlv lies 

 in a knowledge of some vulnerable place in its life history. It is practically 

 impossible to get at the insect while it is hibernating but, if the leaves are 

 thoroughly sprayed with an arsenical poison early in the spring when the 

 beetles begin to feed, many of them will be poisoned. The disinclination 

 of this insect to fly a great distance is encouraging to the man who protects 

 his own trees, since it reduces the liability of their flying from neglected 

 trees near at hand. The local spread of this beetle is slow and the most 

 should be made of it by keeping the pest in check wherever it occurs, even 

 though the infestation be a small one and the injury at the time of little 

 importance. It is a mistake on the part of local authorities to wait till the 

 creature becomes destructive. It should be fought at the very beginning, 

 even before it has .secured a fair foothold in a locality. 



The grubs feed almost exclusively on the under surface of the leaf, 

 rarely occurring on its upper side. The attack usually begins on the upper, 

 more tender leaves, hence the tops of the trees need spraying most, and in 

 order to kill the grubs the poison must be thrown on the underside of the 

 leaves, and, as a rule, this treatment will be found most satisfactory. The 

 full grown larvae crawl down the trunks in great numbers and the golden 

 yellow pupae may be found in abundance in crevices in the bark and on the 

 ground about the trees. Large numbers of these insects can be killed at 

 this time by^ spraying them with a contact insecticide such as kerosene 

 emulsion, whale oil soap solution or by pouring boiling water on them. 



