Leyland Cypress Basal Browning: Canker Diagnosis and Viability Test

10 Leylands (6 ft), lower 3/4 brown, tops green. Owner asks how to tell if dead.

Viability Test

Scrape bark on brown branch: green cambium = alive at that point; brown = dead. Prune dead wood to trunk.

Cause: Seiridium or Bot Canker

Same diseases as Article 12180. Scattered basal death = classic canker symptom.

Management

• Prune dead branches 1″ below canker; sterilize tools.
• Mulch, irrigate drought periods.
• No fungicides.
• Remove if main trunk cankered.

Tops green = partial life. But disease progresses. Monitor closely.