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Canker and Dieback

Multiple pathogens (Phomopsis spp., Botryosphaeria spp., Cytospora spp., and ...

26 host plants

Last updated

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

Canker and dieback causes branch death and plant decline on infected trees. You see sunken cankers that expand and eventually girdle branches. The disease enters through wounds and weak branch unions. Remove infected branches, improve tree structure through proper pruning, and maintain tree health.

Prune out cankered branches at least six inches below visible symptoms, making cuts into healthy wood. Sterilize your tools between cuts. Canker pathogens typically enter through wounds, so minimize pruning injuries and avoid working on trees when bark is wet. Maintain tree vigor through proper watering and avoid stress from drought or compacted soil, which makes trees more susceptible.

Quick Reference

Causal Agent
Multiple pathogens (Phomopsis spp., Botryosphaeria spp., Cytospora spp., and ...
Host Plants
26
Favorable Conditions
Tree stress from drought, frost, poor nutrition, or root damage; fresh wounds...

Management

What Triggers Infection

Tree stress from drought, frost, poor nutrition, or root damage; fresh wounds; wet weather during growing season

Cultural Controls

  • Prune Asian pears during dry periods in the winter, or delay pruning until spring or summer. Summer pruning also helps slow down overly vigorous trees. Thinning flower spurs during dry periods reduces bloom, helps improve fruit size, and may reduce the amount of disease observed. Avoid planting Asian pears in frost pockets or low-lying areas. Do no

Host Plants (26)