Britain’s trees are facing threats from many new pests and diseases, including Chalara dieback of ash. Different areas have different levels of infection and Arnside & Silverdale AONB has not been immune.

The infection is caused by the fungus Hymenoscyphus fraxineus which causes crown dieback, leaf dieback, leaf loss and bark lesions.  Young trees, including coppice, are the most vulnerable to the fungus.

In a woodland, there will be stands of uninfected trees as well as those already affected. Removing infected trees has been shown to slow the spread of infection, but will not stop it.

The advice from the Forestry Commission for low-infection areas is:

DO NOT:

• rush to fell because Chalara is present; or

• feel forced to change planned ash coppicing cycles: stools will either tolerate Chalara or be killed by it, whatever size they are.

DO:

• continue planned work, and consider modifying coppice management as in high-infection areas;

• thin woodland as usual in high forest to maintain tree vigour and a full canopy;

• select trees for thinning that show symptoms of Chalara. This should be done while in full leaf to ensure that uninfected trees are not selected; and

• remove recently planted or naturally seeded trees if small numbers are infected. Burn or bury on site.

It is also recommended, when leaving an infected woodland site, to clean boots and other items to reduce the risk of spreading the disease. Using disinfectant is the most bio-secure, but if not available, brush off any mud and clean with water.

More detailed information and advice can be found in The Forestry Commission’s Managing Chalara dieback of ash in North West England leaflet.