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JOURNAL OF ECONOMIC ENTOMOLOGY 
[Vol. 13 
than is the rule in most fruit regions. These features of the codling 
moth problem, abundance, the variations in seasonal history, and the 
remedial measures necessary, are the subject matter of this paper. 
Particular attention is given to conditions differing from those reported 
by Jenne for 1907 and 1908. It is probable that similar conditions to 
those mentioned below are found in the fruit regions of southern Illi¬ 
nois, and of the Arkansas Valley in Kansas, whose geographical position 
in a general way resembles that of the Ozarks. 
Abundance 
The extent of loss to the apple crop in the Ozarks due to codling 
moth injury is very frequently underestimated by entomologists not 
familiar with this region. This is due in part to the fact that the cod¬ 
ling moth apparently was not a particularly serious problem when 
experimental work was previously carried on here by the Bureau of 
Entomology in 1907 and 1908. In 1907 on the unsprayed check trees 
in the experimental orchard Jenne found only 34 per cent of the apples 
infested with "worms,” and a very satisfactory control was secured 
on the sprayed plats. However, when the writers first came to the 
Ozarks they found the situation very different. There were many 
growers who said that they despaired of ever seeing the codling moth 
controlled and that they expected that at least 50 per cent of their 
apples would be infested by "worms” annually in spite of five or six 
spray applications. 
The general report was that the codling moth problem had grad¬ 
ually become serious, but had been acute only the last few years. One 
was left to assume that this changed status of the pest was due to the 
more intensive development of the apple industry in this region or to 
the gradually cumulative effect of inefficient remedial measures. 
Whatever the cause, the codling moth problem was found to be 
very serious. In 1918, in the check plat of an experimental orchard, 
72.67 per cent of the apples were infested. This percentage does not 
indicate the full severity of the infestation, for in making counts all 
dropped fruits were included. Much of this fruit, which had been 
attacked by scab or had not been pollenated, fell early in the season 
before it had opportunity to be attacked by codling moth. The fruit 
which fell late in the season and that which was harvested was prac¬ 
tically 100 per cent infested. In addition, more than one worm per 
apple was the rule rather than the exception with the apples that 
remained on the trees late in the season. One apple was noted that 
had been attacked by as many as eleven worms. In addition to the 
unsprayed check there were a large number of orchards dusted in 
1918 and nearly all of these and a few that had been sprayed five and 
