IPM is the incorporation of fundamental knowledge and multiple control tactics to achieve adequate control of codling moth. Only through integration of these technique do we minimize outbreaks, preserve pesticides against resistance, and increase economic sustainability.
Considerations for Effective Applications
Without any intervention, codling moth numbers increase about four-fold from generation to generation. Therefore, targeting the first generation is important to reset the population size to a minimum. Control measures for subsequent generations can be adjusted to the local pest pressure indicated by trap counts.
What’s in the pest control toolbox?
The targets for pest management are the adults, eggs, and neonate larvae which are affected by mating disruption, ovicides, and larvicides, respectively. The combination of these three tools has proven most effective in keeping fruit damage below the economic threshold.
Mating disruption is the first line of defense – it delays and prevents mating and egg laying. Mating disruption dispensers need to be in place by roughly 100 DD or bloom, before the first adults emerge at 175 DD; these typically last all season long. Mating disruption is particularly effective as the temperatures increase and will dramatically improve the activity of pesticides applied during the season.
Ovicides are the second line of defense. Eggs can be prevented from hatching with topical or residual pesticides. Oil is a preferred option; it suffocates the eggs that have been laid. Its residue is short – only about 1 day, however, because it kills eggs that have already been laid, it has an effective residue of 150 DD (the length of the egg stage). This is extremely important because it makes oil applications very effective in the early spring compared to the codling moth granulosis virus (discussed below). Oil also tends have a relatively minor effect on natural enemies so it is compatible with Trichogramma parasitoids that have been shown to help suppress codling moth populations by attacking the egg stage.
The third line of defense is larvicides, such as conventional larvicides or codling moth granulosis virus. Both target the newly hatched codling moth larvae which almost immediately bore into the fruit. Therefore, precise application timing is important, because once larvae enter the fruit, they are protected from pesticides. Granulosis virus has a relatively short residual activity (5-7 days), so it is best used in the second generation. Conventional insecticides tend to be active from 12-17 days, so residual activity period is not so sensitive as with the granulosis virus.
IPM Summary
Good IPM practices combine the knowledge of biology, models, and orchard management to implement numerous control strategies. Industry leader and consultant Byron Phillips has deeply considered the influence of all factors to achieve control and sustainable productions. He shares some of his insights in this video.
Apple IPM Reminders
Effective codling moth management as a basis for apple IPM. Mating disruption, monitoring, organic controls. New research. Presented at North Central Washington Tree Fruit Days 2023 co-hosted by WSU Extension, NCW Fieldmens Association, NW Cherry Growers, and Pear Bureau Northwest.
Other Resources
Codling Moth Control: Site-specific IPM
By Kate Prengaman, Good Fruit Grower
Use pesticides with care. Apply them only to plants, animals, or sites listed on the labels. When mixing and applying pesticides, follow all label precautions to protect yourself and others around you. It is a violation of the law to disregard label directions. If pesticides are spilled on skin or clothing, remove clothing and wash skin thoroughly. Store pesticides in their original containers and keep them out of the reach of children, pets, and livestock.
YOU ARE REQUIRED BY LAW TO FOLLOW THE LABEL. It is a legal document. Always read the label before using any pesticide. You, the grower, are responsible for safe pesticide use. Trade (brand) names are provided for your reference only. No discrimination is intended, and other pesticides with the same active ingredient may be suitable. No endorsement is implied.
