23 May 2023
The Natural Environment team is advising Islanders to do an annual check of their sycamore trees
as a widespread disease causes the trees to become brittle and at risk of falling.
Symptoms of infected trees include:
- Branch dieback
- Dry and brittle trees
- Fast decline of infected trees in hot and dry conditions
- Flaking layers of bark
- Sooty black powdery spores on the trunk between bark layers
- Cross section of cut wood has green/brown staining.
If Islanders own a tree that they believe may have the disease, they should contact a tree surgeon
for advice.
FFP3 face masks are recommended when working with infected wood, and care should be taken if
chipping or sawing for extended periods as the spores are hyper-allergenic.
Sooty Bark Disease is widespread in Jersey and most notable in valleys where sycamore trees are
abundant.
Visual symptoms are not always noticeable during cool and damp weather, and only in hot and dry
conditions does the disease become visible through the fast deterioration of tree health and spore
formation.
Sooty Bark Disease is caused by the plant pathogenic fungus Cryptostroma corticale. It has been
present in the UK since the mid-twentieth century but repeated dry summers may have contributed
to the recent impact of this disease.