250 Report oF THE DEPARTMENT OF ENTOMOLOGY OF THE 
with the Virginia results in that the 20 per ct. mixture killed 
he scales, gave very different results with undiluted petroleum. 
In this case, although the petroleum was of the required char- 
acter, testing 43°, it seriously injured or killed all the trees to 
which it was applied. 
From the above review and summary it appears that the exact 
effect of crude petroleum of the proper standard upon both 
scales and trees is not yet fully determined; hence further 
investigation is desirable. 
OBJECTS OF THE EXPERIMENTS. 
The experiments with crude petreleum reported in this bul- 
letin were undertaken principally with a view to adding further 
data as to its effect upon both scales and trees. Conflicting 
results with this insecticide in the hands of Western New York 
orchardists have also made a series of experiments in this sec- 
tion of the State desirable. 
CONDITION AND CLASSIFICATION. 
The experiments were conducted in a number of different 
orchards, all of them in western New York. In each case the 
condition of the trees was carefully noted. 
The crude petroleum used was purchased of the Standard Oil 
Company. It was dark green in color and had a specific gravity 
of 44°. 
An emulsifying pump of the type that emulsifies the oil and 
water at the nozzles was used in all of the experiments. The 
Spray was very fine and the emulsion thus made was excellent, 
the oil being so thoroughly broken up that it did not whoily 
separate from the water in the 1,000 cc. graduate in which the 
tests were made for over two days. 
To avoid error in the amount of oil applied the pump was 
frequently tested. These tests showed only very slight varia- 
tions in the percentages. 
Much pains was also taken to make the applications thorough 
and uniform. The spray was directed upon the tree until it 
