26 THE CONTROL OF APPLE BITTER-ROT. 
croup of plots that the ideal treatment would have been five applica- 
cations at intervals of two weeks, beginning June 12. Comparing 
Nos. 12 and 15, it is further noted that a delay of two weeks—from 
July 10, the date the first application was given No. 15, to July 25, 
the date treatment began on No. 12—made a difference of 37.3 per 
cent in favor of the earlier applications, representing the difference 
between success and failure. 
Considering the series of Plots 2 to 8, which combine the three early 
applications for scab and the later applications for bitter-rot, No. 3 is 
the most satisfactory. This plot was sprayed seven times, namely, on 
April 8, May’1, and May 9 for scab, and on June 12, June 27, July 
10, and July 25 for bitter-rot, and the result was 56 bushels of sound 
fruit and only 2 bushels of rotten fruit from the two trees, or 96.5 
per cent of sound fruit. Plots 4,5, and 6 each had a slightly larger 
percentage of sound fruit, but scarcely enough to pay for the addi- 
tional spraying which they received. However, the bitter-rot fungus 
is so influenced by weather conditions that it is scarcely safe to follow 
No. 8 and stop spraying as early as July 25. The treatment (eight 
applications) given Plot 4 would doubtless be necessary In some seasons 
to prevent both scab and bitter-rot. The results obtained in Plots 15, 
16, and 17 seem to indicate that four applications at intervals of two 
weeks, beginning June 12, June 27, or even as late as July 10, would 
be the most satisfactory treatment, when the cost of spraying is con- 
sidered, but as a rule it pays to give three or four treatments earlier 
in the season for apple scab, leaf-spot, and codling moth, and, there- 
fore, these early spring applications, combined with the early summer 
applications, undoubtedly give the most satisfactory results. 
The lesson to be learned from Plots 7 and 8, as compared with Plot 
6, is that the omission of the June and July applications is almost 
fatal to the crop. Comparing Plots 7 and 8, it is seen that the one 
extra application given to the former on July 25 resulted in a saving 
of 28.4 per cent over the latter. Again, comparing Plots 11 and 12, 
it is seen that one extra application given to the former on July 10 
resulted in a saving of 33.1 per cent over the latter. These results 
emphasize the importance of spraying at the right time, and in order 
to be sure of covering the proper time the applications must be spread 
out over a long period. 
EFFECT OF THE TREATMENT ON OTHER DISEASES. 
Scab.—It is already well known that apple scab is easily controlled 
by spraying with Bordeaux mixture. This disease was completely 
prevented on the trees in the experimental plots receiving the three 
early applications, namely, first, just before the trees bloomed; second, 
as soon as the blossoms were shed, and third, eight days later. Some 
scab appeared on the trees not so treated, but this variety of apple 
