94 BULLETIN 352, U. S. DEPARTMENT OF AGRICULTURE. 
strengths of arsenate of lead would be likely to cause severe injury to 
peach foliage. The addition of 2 pounds of soft soap or 1 pound of 
hard soap to 50 gallons of the mixture has been generally found to 
increase the effectiveness of the nicotine sulphate. 
_ Sweetened arsenate of lead is recommended for cherry trees because 
of its efficiency in killing the beetles and because its effect is con- 
tinuous in favorable weather. Rain destroys the effectiveness of 
this spray. The combination found most useful is 5 pounds of arse- 
nate of lead, 14 gallons of molasses, and 50 gallons of water. 
If the beetle migration should occur during a rainy period, the 
unsweetened arsenate of lead might be most useful. 
In applying a poison spray care must be taken to cover the under- 
side of the leaves where the beetles feed. Im some instances it may 
be necessary to spray only young cherry trees or older trees of the 
thin-leaved varieties. In large orchards into which the beetles are 
migrating in great numbers it is advisable to spray first the trees 
most susceptible to attack, for during the season of 1915 the maxi- 
mum injury occurred immediately after the first arrival of the beetles. 
In no case should the sweetened arsenate of lead be used with Bor- 
deaux mixture as a combination spray, for burning of foliage is 
likely to result. 
