324 Report OF THE DEPARTMENT OF ENTOMOLOGY OF THE 
plication were not quite so exempt from mites as the earlier-sprayed 
lot, but the condition of the trees was very satisfactory and sur- 
passed that of the blocks contemporaneously sprayed with either 
kerosene emulsion or whale-oil soap. The cost of the spraying 
mixture for each tree was four cents. 
Kerosene oil.— The trees sprayed with oil. suffered a retardation 
of the leaf-buds, the effects of which were apparent for nearly 
one month after the appearance of the leaves on the checks. ‘The 
amount of blossoming was small and none of the fruit set. One 
of the trees, which was much infested during the previous year, 
was entirely exempt from leaf galls. The remaining three trees 
showed slight traces of the mites which were due to obstructions 
in spraying. Since 1902 none of the trees in the entire orchard 
has shown so little evidence of the mites. These trees at the last 
examination on August 7 had made a thrifty growth and, with 
the exception of the loss of fruit, were in an excellent condition. 
The average cost of the oil for each tree was twenty cents. 
Kerosene emulsion.— The trees receiving this treatment were 
more free from the mites than were the trees sprayed with whale- 
oil soap. The infestation was more abundant than existed in the 
blocks treated with miscible oil and pure kerosene oil. It was 
estimated that about 50 per ct. of the leaves were infested as 
compared with the checks. The applications of the kerosene emul- 
sion caused no apparent injury to fruit and leaf buds and the fruit 
yields were fully as large as those of the checks. The cost of the 
emulsion for each tree was five cents. 
Whale-oil soap.— The application of the whale-oil soap appeared 
to have had very little effect upon the mites; and the trees, with 
the exception of some of the lower branches, were fully as badly 
infested as the checks. The spraying in this case was just as 
thorough as the other treatments, and the only reasons that can 
be given for these results are that the soap was not used strong 
enough or that this spray is not adapted for penetrating the pub- 
escence of the buds and the bud scales. The cost of the soap solu- 
tion for each tree was five cents. 
Conclusion.— In this year’s work the mite was greatly reduced 
in numbers by several sprays, an accomplishment which was appar- 
ently due to early treatment and to the use of oil sprays which 
