REPORT OF THE DEPARTMENT OF ENTO- 
MOLOGY. 
COMMERCIAL MISCIBLE OILS FOR THE 
TREATMENT OF THE SAN 
JOSE SCALE.* 
Porro ly, .t.. i FODGKISS Ann kb; A] SIRKINE. 
SUMMARY. 
This bulletin contains the details of a number of experiments with 
commercial miscible oils to determine their merits for the control 
of the scale. This work was conducted in three orchards in which 
1368 trees were sprayed with these preparations in varying pro- 
portions. On the basis of these tests the following conclusions are 
drawn: ¢ 
Applications of proprietary miscible oils at the rate of one part 
of oil to twenty or twenty-five parts of water failed to give uniform 
results on scale. Trees receiving these treatments usually showed 
more or less spotting of the fruit and varying infestation of the 
new growth. 
Miscible oils in the proportion of one part of oil to ten or fifteen 
parts of water, while uniformly more destructive to the scale than 
the weaker preparations, were usually not quite so efficient as the 
boiled lime-sulphur wash. These stronger applications destroyed 
large percentage of the scales, being sufficiently effective to maintain. 
the thriftiness of the trees and to keep the fruit crop fairly clean. 
On the basis of these results even the better ones of the miscible 
oils tested should not be used in weaker mixtures than one part to 
ten or fifteen parts of water. 

*A reprint of Bulletin No. 281. 
19 289 
