Cydia Pomonella (Codling Moth)
Codling moth is a major insect pest of apples and other fruits
and nuts worldwide. Its larvae damage fruit by feeding on the
seeds at the core. As with other insects whose larvae burrow
within, during this portion of its life, codling moth is safe
inside the apple, and there are no means to stop it except
removing and disposing of the fruit. Thus, control strategies
concentrate on killing the eggs and larvae before burrowing
Codling moth has been known since antiquity and has spread from
one apple-growing region to another in infested fruit.
This page is about confronting this pest from the point of
view of a backyard gardener who cannot lavish full-time
attention upon detecting and defeating it and who does not have
access to techniques applicable to large-scale commercial apple
The backyard gardener is at considerable disadvantage from the
start because his crop must be brought to harvest in the
presence of neglected culinary and ornamental trees on his
neighbors' property. It is from these nearby sources of
infestation that codling moth invades his premises and
establishes itself there.
In addition to outlining the lifestages of the codling moth and
describing horticultural tactics to minimize its impact, this
paper describes chemical-control strategies. Successful use of
chemicals requires applying sprays at the right time, so this
paper also describes tracking the weather and demonstrates the
Phenology Extension to
Instrumentation software for backyard weather stations.
Lifestages of the Codling
Most of this page concerns the codling moth (Cydia
pomonella) specifically, and the goal is to explain how to
use high technology, which is within the reach of the backyard
gardener, to control this pest, but the technology can be
directed toward other pests, of course, and some gestures are
made in that direction, as well.
Over the years, several techniques have been developed to
combat codling moth. Chemical control remains the most
economical for the backyard gardener because the chemicals
prescribed continue to evolve, but no single technique,
including chemical control, is sufficient. These techniques
are usually practiced in some combination.
How to Track Growing Degree
Changing the weather is not considered a practical way to
control codling moth populations in backyard orchards. As it
has spread to various climates around the world, codling moth
has evolved to survive under most weather conditions.
Tracking increasing temperatures in the spring, however, can
predict the synchronized pupation and emergence of adults from
overwintering cocoons as well as the succeeding developmental
stages (egg laying and egg hatching). This section presents
the technique for predicting these stages. The resulting
predictions may then be used to conserve chemical controls for
use at the most effective times.
Chemical control of codling moth is expensive, but it is the
most efficient method for the backyard gardener. All the
methods described, above, act to
cut down on the population of moths but do not completely
eliminate damage. The same goes for chemical control, but
chemical control applied at the right time can be the most