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Twig Dieback and Canker

Phacidiopycnis washingtonensis

12 host plants

Last updated

Data Coverage 3 of 6 dimensions
Causal Agent
Host Plants
Symptoms
Management
GDD Threshold
Regional Notes

Crabapple twigs and branches develop light-brown cankers and die, with visible fruiting bodies and mummified fruit. Phacidiopycnis washingtonensis and Sphaeropsis pyriputrescens spread via spores from infected tissue. Remove and destroy cankers, dead twigs, and fruit. Avoid overhead irrigation and reduce over-tree cooling time. Crabapple pollinizers are particularly susceptible.

Remove and destroy cankers, dead twigs, and mummified fruit. Avoid overhead irrigation. Prune affected branches well below visible symptoms and sterilize tools between cuts. Avoid pruning during wet weather, which spreads the pathogen through fresh wounds. Maintain plant vigor through proper watering and site management.

Quick Reference

Causal Agent
Phacidiopycnis washingtonensis
Host Plants
12

Management

Cultural Controls

  • Remove and destroy cankers, dead twigs, and mummified fruit.
  • Avoid overhead irrigation.
  • Limit over-tree cooling to keep trees wet for shorter periods of time.

Host Plants (12)