REPORT OF THE STATE ENTOMOLOGIST 1918 17 
INJURIOUS INSECTS 
CODLING MOTH 
Carpocapsa pomonella Linn. 
Experimental work to test the relative efficiency of one, two and 
three applications was continued in the orchard of G. W. Mead, 
Barker. A general description of the orchard and the location of 
the plots has been given in the Report for 1917 (see pages 18 and 
1g) and need not be repeated here. 
The first application was made May 27th and 28th. Two and 
one-half pounds of paste arsenate of lead were used to 150 gallons of 
water and a gallon of standard lime sulphur added to each 4o of the 
spray. This, the regular calyx application, was made to three plots, 
300 gallons being used and some burning of the foliage resulted. 
The application was supervised by J. B. Achilles. 
The second treatment was given to plots 1 and 2 July oth, 170 
gallons of spray being used. This was followed by a serious yellowing 
and dropping of the foliage. The work was supervised by L. F. 
Strickland. 
The third spraying was given July 26th, to plot 3, 60 gallons of 
Spray were used. The proportions were the same as in the earlier 
treatment. Throughout the work a Gifford spray gun was employed 
and the pressure was maintained at 225 pounds. 
The apples were picked in early October and classified by L. F. 
Strickland, agent, Department of Farms and Markets. He was 
assisted in this work by J. B. Achilles and T. T. Neill of the same 
department. The fruit on the six trees of each of the three plots 
and that on the two check trees was carefully classified, and an 
examination of the complete data shows in the case of plot 1, sprayed 
once, a codling moth infestation ranging for individual trees from 
6.18 to 18.28 per cent or for the plot 10.17 per cent wormy fruit. 
In plot 2, the ranges were from 3.7 to 19.45 per cent of wormy apples, 
the plot per cent being. 10.66. Similar figures for plot 3 showed a 
variation from 5.34 to 15.95 per cent, the per cent for the plot being 
g.10. These wide differences are due in part to great variation in 
the yield and probably also to the difficulty in doing equally thorough 
work with a nozzle which demands very rapid operation, if one 
would avoid overloading the trees with spray. With these facts 
in mind it was deemed best to make selections from each plot, taking 
trees which bore at least a moderate crop and those which did not 
deviate widely from what we judged to be the normal. This latter 
consideration resulted in the elimination of tree F on plot 3 because 
