16 BULLETIN 959, U. S. DEPARTMENT OF AGRICULTURE. 
and with a mixture containing 10 per cent of lead arsenate there was 
only 14.38 per cent of uninfested fruit, all of which would indicate 
practically no control. Furthermore, the dust was not nearly so 
effective as the liquid sprays in preventing the entrance of worms at 
the calyx. 
The two plats sprayed by the grower, plats XIV and XV, produced 
a lower percentage of control than those treated by the experimental 
staff. Plat XIV, in which spray poles and Bordeaux nozzles were 
used throughout the season, yielded 40.21 per cent of uninfested 
fruit, whereas plat XV, in which the spray gun was employed for the 
cover sprays, gave but 30.22 per cent of worm-free fruit. 
The abundance of the codling moth in this orchard is indicated in 
plats XVI and XVII, both of which were untreated and which pro- 
duced but 8.83 and 8.54 per cent of worm-free fruit. The number of 
stings in these plats, as was to be expected, was not large, there being 
88.16 per cent of fruit free from stings in plat XVI and 87.42 per cent 
in plat XVII. It will be further noted that in these plats the per- 
centage of calyx worms was large, 30.26 and 28.92 per cent, respec- 
tively, with 47.09 and 47.50 per cent of the wormy apples infested at 
the calyx end. 
Copuinc-MotH Trap EXPERIMENTS IN 1917. 
A section of the J. B. Hunter orchard near Fruita, Colo., consisting - 
of Ben Davis and Gano apple trees, was divided into three plats. 
Plat I, containing 60 trees, was banded and sprayed; plat II, having 
108 trees, was provided with the codling-moth trap and sprayed; 
while plat III, 99 trees, received no other treatment than five spray 
applications as described below. . 
The spray applications, five in all, were made by the grower on all 
the plats as follows: Calyx spray applied June 1-2; first cover spray 
June 14-16; second cover spray July 11; third cover spray July 27; 
fourth cover spray August 16.. A power sprayer was. used throughout 
the season and this was equipped with Bordeaux nozzles for the 
calyx application and whirlpool-disk type nozzles having a large 
aperture disk for all of the cover treatments. 
The data obtained from the examination of the dropped and har- 
vested fruit from eight trees in each plat will be found in Table 11. 
It will be noted therein that plat III, which had only the spray 
treatment, produced 76.56 per cent of fruit free from worms, a higher 
percentage than that of plats I and II, which received theoretically 
better treatments. There is no logical explanation for these results 
other than the possibility of unevenness of infestation and yield of 
fruit. 
