Nectria Twig Blight (Coral Spot)
Nectria cinnabarina
13 host plants · Fungal
Last updated
This profile contains verified disease data from extension databases. Regional field notes and expert review are in progress.
Apple twigs develop small sunken cankers with bright coral-red fruiting bodies, gradually girdling branches over years. Nectria cinnabarina is a wound invader following pruning and fruit picking. Make short pruning stubs, remove dead wood, instruct pickers to avoid stem damage. The fungus has a wide host range.
Remove blighted tissue promptly, cutting well below visible symptoms. Improve air circulation by thinning dense growth. Avoid overhead watering, especially during bloom and new growth periods when tissues are most susceptible. For recurring problems, preventive fungicide applications timed to protect new growth can reduce infection, but cultural controls should be your first approach.
Quick Reference
Management
Any time wounds are present; peak risk during dormancy (Oct–May). Pruning wounds in winter and spring are most vulnerable because callus formation is slow. Fruit pedicel wounds at harvest (late summer) become infected and remain active sources of inoculum. Broken branches from wind, ice, or snow damage create high-risk sites (BBCH 97–09).
Wounds are the critical requirement for infection; Nectria cinnabarina is an obligate wound invader. Cool, moist conditions (fall, winter, spring) favor canker development and spore production. High humidity and prolonged leaf wetness promote spore germination on fresh wound surfaces.
Cultural Controls
- Make clean, short pruning stubs
- Remove and destroy infected or dead wood
- Instruct pickers not to leave fruit stems on tree
- Prune only during dry conditions