Strategy launched to manage declining Ash trees suffering from Ash dieback

28th February 2023


A bold plan to manage the declining health of ash trees suffering from ash dieback disease has been launched across Three Rivers District Council owned woodlands and open spaces.

Under a new long-term council strategy, some ash trees in high safety risk locations will be felled or pruned to deal with the impact of the disease. In low-risk areas, where safe, trees will have their branches removed and will be left as important standing deadwood habitats for specialist insects, fungi and bats.

In many locations felled timber will be stacked on-site as habitat piles or, where possible, may be sold as firewood to reduce the cost of the works.

Over recent months, the council’s tree officers have been encountering increasing numbers of ash trees in poor health resulting from ash dieback, in particular at Rickmansworth Aquadrome, Oxhey Woods, Batchworth Heath, Chorleywood House Estate and Carpenters Wood.

Ash dieback is caused by an airborne fungus, and affects a range of ash species, but notably common ash, the UK’s native species, which is widespread across Three Rivers district. The disease has a high mortality rate (60-70%) rapidly killing saplings and young ash trees. In mature specimens, it can re-infect trees in successive years, leading to a longer-term gradual decline in overall tree health. Weakened trees are likely to become infected by other tree pathogens, and eventually reach an unsafe condition which requires them to be felled.

Cllr Phil Williams, the council’s Lead Member for Environmental Services, Climate Change and Sustainability, said: “This plan is all about taking action and protecting our trees in a proportionate and cost-effective way. This new programme of planned tree works will focus on areas of highest risk where trees are in poor health. This will reduce the cost of works by reducing the need for repeated visits by tree surgeons to over the longer term; and which can also be very disruptive to residents and business.

“Many of our ash trees are growing in woodlands where the natural regeneration of other tree species will replace the felled trees. The gaps created by the loss of the trees will bring more light and some ecological benefits, but we will be looking at replanting in some locations.”

The council’s current Tree Strategy identified ash dieback as a key issue for the district, and concluded that it should take a risk-based approach to managing declining ash in line with guidance from the Forestry Commission.

The project is beginning shortly with work to trees at the Rickmansworth Aquadrome.

Read the council’s Tree Strategy here: