Codling moth on apples
On apples the larva enters at the calyx (eye) end or the side and tunnels to the core, leaving a hole plugged with reddish-brown frass. UC IPM notes that late-maturing varieties are more likely to be badly damaged than early ones. The granulovirus has to be on the fruit when the eggs hatch, because a larva that has bored in is out of reach; the Cyd-X and Madex HP labels say to spray at least twice per generation and to reapply after 7–8 sunny days (6–8 on the Madex HP label), while UC IPM's backyard advice is weekly sprays, three or four per generation. UC IPM adds that 1% horticultural oil in the tank improves both the virus and spinosad. Bagging the fruit at ½–1 inch is the alternative that needs no spray at all.
At a glance
- Damage
- Worm holes in apples and pears, with brown frass at the entry and a tunnel to the core
- Type
- Chewing
- Settings
- Garden, Field
- Threshold
- No home-garden threshold; start at first egg hatch
- Ally
- Betabaculovirus cypomonellae (Cydia pomonella granulovirus)
- Rate
- Label rate — Cyd-X 1 tsp per 5 gal of water; Madex HP ½ tsp per 5 gal (homeowner labels)
How to confirm it
A hole in the fruit plugged with crumbly reddish-brown frass, often at the calyx end, and a tunnel running to the core. Cut the fruit open: a white to pinkish caterpillar with a dark brown head, up to ¾ inch long, is most likely codling moth; oriental fruit moth looks almost the same.
Identification, lifecycle, degree days and every control option are on the full Codling moth profile. Not sure it is this pest? Answer four questions about the damage.