symptoms
Symptoms
- circleBlue-black staining of roots and lower stem tissue
- circleSparse, yellowing foliage and thin canopy
- circleDark fluid oozing from cracks near the base of the trunk
- circleSudden wilting and dieback, particularly in sweet chestnut
help
Causes
Caused by soil-borne Phytophthora species that infect roots and the root collar, favored by wet, poorly drained soils where the pathogen's motile spores can spread easily.
healing
Treatment
There is no effective chemical treatment; remove and destroy severely affected trees, including stump and major roots where feasible, to limit soil contamination.
shield
Prevention
Improve soil drainage, avoid planting susceptible species in low-lying wet ground, and avoid moving soil or water from infected sites to clean areas.