At a Glance
- Codling moth is a major pest of apples and pears in the Okanagan.
- Larvae feed inside fruit, causing internal damage and contamination.
- Damage appears as stings or frass at entry/exit holes.
- Once inside the fruit, larvae are difficult to control.
- Pheromone traps and monitoring are essential for timing control.
- The BC DAS system helps track development and optimize spray timing.
Why Is Codling Moth a Problem?
The codling moth is a common pest of apples and pears in the Okanagan Valley. Larvae feed within the fruit, causing damage that may appear as small surface stings or frass at entry or exit holes. This internal feeding damage renders fruit unmarketable and can significantly reduce pack‑out quality and returns.
Where Does Codling Moth Come From?
Codling moths overwinter in cocoons within orchards (on tree trunks, bins, or woodpiles). In spring, adults emerge, mate, and lay eggs on developing leaves and fruitlets. After approximately 10–14 days, larvae hatch and tunnel into fruit, where they feed on seeds. Once inside the fruit, they are protected from many control measures. Pheromone traps are an important tool for monitoring populations. Trap data, including information from the Sterile Insect Release (SIR) program, helps growers understand population levels and assess the need for control.
For best results, trapping information should be used together with the BC DAS Codling Moth model to determine not only if, but when to take action.
How the BC DAS System Helps
The BC DAS system provides information on the timing of adult emergence and egg laying based on local orchard conditions. Using degree‑day accumulation along with temperature data, the system predicts key stages of development, including the beginning of egg laying at approximately 230 degree‑days. Combined with forecast data, the system sends alerts to help growers apply control measures at the optimal time.
The DAS Spray Guide provides spray options, rates, and timing recommendations. Growers can plan programs with or without mating disruption (MD) and select products registered for conventional or organic use. By following the BC DAS model, growers gain access to timely information and tools to improve control and reduce codling moth damage.
Learn More (Video)
Interested in finding out more? Check out the BC DAS Codling Moth model video to connect field knowledge with the online DAS system.
For more information, contact the Okanagan‑Kootenay Sterile Insect Release Program (SIR): https://www.oksir.org