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tant features of the control of this insect. The writer has made many 
observations as to the efficiency of the spray. It is a common thing 
in sprayed orchards to find places on the apples where larvae had 
entered and, a day or two after entering, had died. This condition 
was found to be much more frequent in sprayed orchards than in those 
which were unsprayed. Without doubt these larvae were killed by 
the spraying. Exactly how and when the larvae get the poison is a 
question. As has been stated before, the larvae eat but little of the 
skin or flesh of the apple while entering. The cavities in which they 
are found dead are usually of such size that it would take the larvae a 
day or two to make them. Particles of lime are sometimes found in 
these cavities. While seeking a place of entrance the larva may get 
some of the poison, and it may live a day or so after getting the fatal 
dose. Some of the spray may get into the entrance hole and be eaten. 
Soon after dying, the larvae become dry and shrunken and can be 
distinguished only by the presence of the head. 
The writer once noted a case where 70 cent of the larvae entering 
in the course of two or three days were found dead. It is extremely 
probable that a considerable part of them died naturally. Many 
other observations were made, but never was such efficiency noted 
again. 
In many orchards that had been well sprayed, hundreds of these 
spots were noted which had been caused by the larvae and upon exam- 
ination no larvae were found. 
In 1901 the writer found a larva which had begun an entrance hole 
and had just died. 
On account of these observations and the general results obtained 
by spraying and banding, the writer has no hesitancy in recommend- 
ing these later sprayings. Without doubt the efficiency is much less 
than in case of the first spraying, but the writer believes them well 
worth the expense. 
The writer has found that many growers spray when they have 
time and do not take into consideration the stage the insects are in. 
Some spray every three weeks and others spray when they see the 
number of entrance holes increasing. As already shown, the larvae 
are entering more or less all summer; but at two certain periods of 
the season there are many more entering than at other times. One 
can easily see that the theoretically perfect time for spraying would 
be when the larvae are entering the fruit in greatest numbers. It is 
therefore essential to recommend simple, practical methods for deter- 
mining this period of greatest entrance. The writer advises every 
one who wishes to spray for the codling moth to keep a daily band 
record on about 1 trees. By a study of this record the maximum can 
be easily found. In the summer this maximum will be found some- 
times between June 25 and July 15. By experiment we have found 
