APPLE PESTS 
from Mediterranean regions to the north- 
ern limits of apple growing in Siberia, 
in Southern Africa, Australia, New Zea- 
land, Tasmania and China, as well as 
in the United States and Canada, we 
are forced to recognize the improbability 
of perpetually immune regions Once it 
gains a foothold the codling moth will 
thrive wherever the apple can be grown 
successfully. 
We do not wish to be understood as 
arguing that the codling moth will be- 
come equally destructive in all localities, 
or that its prevalence is independent of 
climatic conditions. Rather the contrary 
is true, since the seriousness of its depre- 
dations varies with both the locality and 
the season. Temperature is the great fac- 
tor which controls the abundance of a 
species in a given locality; hence, as the 
female moth deposits eggs freely only 
when the evening temperature is above 60 
degrees Fahrenheit, we should expect to 
find, as indeed we do find, that the orch- 
ards in the coast regions west of the Cas- 
cades, and those of the inland plateau 
sections, are less subject to the ravages 
of the codling moth than those of the in- 
land valleys. This factor is of but little 
practical importance, however, and should 
be given scant consideration in the selec- 
tion of an orchard site. The probability 
is that as orchards become More numer- 
ous, active repressive measures against 
the codling moth will become necessary, 
even in the most favored localities. 
Know All Stages—Efficient spraying 
operations and the proper application of 
other repressive measures against the 
codling moth are so intimately linked with 
its habits, and these habits so varying, 
within certain limits, with the locality and 
the season, that every grower should be- 
come familiar with it in all of its stages. 
Unfortunately, however, growers do not 
seem fully to recognize the importance of 
such information, or consider it too tech- 
nical and difficult to obtain. Consequent- 
ly few actually do know it in any other 
than the larval or “worm” stage, not- 
withstanding the fact that a “speaking 
acquaintance” with all stages is easily 
acquired. 
515 
The codling moth, in common with 
many other insects, passes through four 
Sharply defined stages during its develop- 
ment, viz.: the egg, the larva or “worm,” 
the pupa, and the moth or adult. All 
four stages from the egg to the moth 
inclusive constitute a generation or a 
“brood,” and since this cycle from egg to 
moth is completed twice during the year, 
the insect is said to pass through two 
generations yearly, or to be “two 
brooded.” In some of the warmer apple 
growing sections of the South three 
broods are reported. During the winter 
it exists only in the larval state, but dur- 
ing a greater portion of the summer 
months it may be found in all four 
stages. 
The Hgg—The eggs, which are laid 
singly, are minute, nearly circular scale- 
like objects about one-twentieth of an 
inch in diameter, pearly white in color 
and somewhat translucent. They may 
well be likened to minute trout scales 
glued to the surface of a leaf or fruit. 
The surface of the egg, however, is finely 
wrinkled and so reflects the light that it 
appears as a minute glistening speck, if 
the fruit or leaf to which it is attached 
is held at the correct angle before the 
eye. In two to four days after oviposi- 
tion the developing larva becomes dis- 
tinctly visible as a black spot near the 
center of this circle and the outline of 
the whole body is discernible for a day 
or two before the egg hatches. The eggs 
hatch in from seven to ten days. 
The Larva—When first hatched the 
young larva is searcely one-sixteenth of 
an inch long. The head is large, black 
and shining; the body is slender, translu- 
cent white in color and marked with dis- 
tinct black spots, each of which has a 
minute bristle. Owing to their minute 
size and to the fact that they usually 
enter the fruit very soon after hatching, 
these young larvae are rarely seen. AS 
the larva develops it molts five times; 
the color of the head and the thoracic 
and anal shields turn black to brown, and 
the body acquires a pinkish tinge. The 
full-grown larva is about three-fourths of 
an inch long and one-twelfth of an inch 
