5   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 begins.

Painting: Adam and Eve

Adam and Eve (1517, Holbein)

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 back-yard 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 culture.

The back-yard 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 the WeeWX Instrumentation software for back-yard weather stations.

  • Lifestages of the Codling Moth

    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.

  • Horticultural Practice

    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 Days

    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

    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 effective.