Twig Dieback and Canker

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.