Phytophthora bleeding canker

Phytophthora bleeding cankers are infections of the bark of trees by various species of the fungus-like organism Phytophthora. Infection causes bark lesions (cankers) that bleed a dark or reddish- brown sticky fluid.

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A beech tree infected with Phytophthora kernoviae. Image: Forest Research

Quick facts

Common name Phytophthora bleeding canker
Scientific name Various Phytophthora species
Plants affected Various trees including Aesculus (horse chestnut), Tilia (lime) and Alnus (alder)
Main symptoms Cankers oozing a dark sticky fluid
Caused by Fungus-like (Oomycete) organism
Timing Symptoms seen all year

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