Common canker

Common canker produces cankers on tree bark that gradually girdle and kill branches. You notice sunken lesions with stained wood beneath the bark surface. The disease spreads from wounds during moist weather periods. Prune out infected wood and avoid creating tree injuries.

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.