Fusicoccum Canker (Godronia Canker)

Blueberry stems develop bull's-eye cankers at leaf scars or wounds on current growth, eventually girdling and killing branches. Godronia cassandrae (Fusicoccum) spreads via rain-splash during wet springs. Prune out cankered wood, sanitize tools, avoid overhead irrigation, and grow tolerant cultivars like Rubel or Rancocas rather than highly susceptible Bluecrop.

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.