Codling Moth

📐 FIELD GUIDE ILLUSTRATION

Original illustration by PestControlBasics.com. Use the labeled features above to confirm your identification.

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PestControlBasics Editorial Team

Reviewed by Derek Giordano · Updated 2026

🔍 Identification

Adults: 10-15mm wingspan; grey with bronze-brown wing tip pattern. Larvae: pink-white with brown head; 12-18mm; found tunneling through apple or pear flesh toward the core. Entry hole: tiny on fruit surface with brown frass. Found inside apples, pears, quinces, and occasionally walnuts.

🧬 Biology & Behavior

Adults emerge from overwintering cocoons when temperatures accumulate (degree days). Mating and egg-laying occur after a specific temperature threshold. Larvae hatch and bore directly into developing fruit. Pheromone traps catch adult males — when trap catches increase (indicating male flight), egg hatch follows within 250 degree days. Commercial orchards use degree-day models to time spray applications precisely within this window.

⚠️ Damage & Health Risk

Internal fruit damage (the classic wormy apple); early fruit drop from infested fruit; cosmetic damage making fruit unmarketable; 2 generations per year in most US apple regions.

🔧 DIY Treatment

Pheromone traps (CP lures) for monitoring adult flight — essential for timing. Kaolin clay applied to fruit when covers close and throughout growing season deters egg-laying and larva entry. Spinosad spray timed to egg hatch. Codling moth granulosis virus (Cyd-X) — OMRI organic; specific to codling moth.

👷 When to Call a Pro

Commercial apple/pear: spray program guided by degree-day monitoring; conventionally: organophosphate or pyrethroid at egg hatch; organic: spinosad + kaolin rotation.

❓ FAQ

How do I know when to spray for codling moth?

Set up a pheromone trap (available from garden suppliers) near your apple trees. When you catch 5+ moths per trap per week, egg-laying is active and treatment window is open. Spray spinosad or apply kaolin clay during this window. Trap monitoring removes the guesswork about timing.

What is codling moth granulosis virus?

Cyd-X (CpGV) is a naturally occurring virus specific to codling moth larvae — it infects and kills larvae that hatch and bore into fruit. OMRI organic certified. More effective than any synthetic insecticide at preventing internal fruit damage because it remains on the fruit surface and kills larvae immediately upon entry. Requires frequent reapplication (every 5-7 days) because UV degrades the virus.

🐛 Codling Moth