Field Identification
A bacterial disease causing raised, corky lesions on leaves, fruit, and twigs surrounded by oily yellow halos. Wind-driven rain splashes bacteria; leafminer tunnels can increase infection courts. Report suspect trees where the disease is regulated.
Lesions are tan to brown with a water-soaked margin on both leaf surfaces; fruit spots crack and roughen. Severe infections defoliate and weaken trees.
How to Deal With It
Organic Control Methods
Plant windbreaks to reduce tearing wounds, use certified nursery stock, and disinfect tools. In quarantine areas, comply with removal orders to protect neighbors.
Copper-tolerant antagonists and competitive leaf microflora are research targets; healthy soil biology supports overall tree resilience.
Prune for airflow but avoid excessive wounding; manage leafminer to reduce entry points; avoid working wet foliage.
Remove and destroy infected branches and fruit on a small scale when allowed; bag material for disposal per local guidance.
Copper-based bactericides (approved for organic in your program) applied on calendar or infection-risk windows; limited efficacy means integration with sanitation and resistant varieties where available.
Let Nature Handle It
Natural Enemies
- Antagonistic Bacteria
- Beneficial Leaf Microbes
Threat Map