Life cycle of the codling moth

  1. Mature larvae over winter in a silken cocoon under loose bark, in soil or in debris around the base of the tree.
  2. When the first blossoms show pink the larvae change into pupae.
  3. At about full bloom the adults emerge from the pupae and begin laying eggs on leaves and sometimes on fruit.
  4. Larvae emerge from the egg in 6-20 days (temperature dependent). Larvae at hatch is about .1 inches long. Larval stage lasts 3-4 weeks. This is the damaging stage of the codling moth. The larvae can create a “sting” on the side of the fruit which just produces a small wound or it can burrow into the center of the fruit usually from the flower end (end where the flower remains are) or from the side. This entry area will show frass (larval excrement) as the larvae feed and grow.
  5. Once the larvae are mature they spin a silken cocoon and either over winter or immediately pupate for 2-3 weeks to hatch into adults in mid-July and August.
  6. Adults of the second generation fly in July and August and lay their eggs. The larvae hatch from this generation is the one that does the most damage.

If the first generation of codling moth is well controlled there will be limited second generation therefore, limited damage.

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