266 TWENTY-FIFTH ANNIVERSARY REPORT. 
arsenical poisons as a means of combating this pest in the nursery. 
To ascertain the effects of these insecticides upon the beetles, a 
number of experiments were made which showed conclusively that 
thorough spraying with an arsenical poison of poplar and willow 
plantations about July 15 will materially reduce the number of 
beetles and thereby lessen the number of eggs deposited in the 
trees. Attention of nurserymen was called to these observations 
and experiments by the publication of Bulletin No. 286, which gives 
a complete account of this insect and directions for the prevention 
of injury and the control of the beetles. 
