Ash dieback prognosis

By Councillor Steve Kay

The fungal disease chalarafraxinea, more commonly known as ash dieback disease, is about to have a devastating effect, not only on Redcar & Cleveland’s natural environment, but also, in these hard times, on the public purse.

Ash dieback has been present in the UK for a decade but,on our patch, it took hold during the covid pandemic (Not that there’s any biological link between the two diseases!). Ash dieback is caused by a fungal pathogen, hymenoscyphus fraxineus which infects the vascular system of the tree. It’s equivalent to blocked arteries in humans. Nutrients and water are prevented from getting from the roots into the canopy of the tree, reducing photosynthesis, causing structural weakness and, eventually,catastrophic collapse.

Infected saplings usually die within a year, but mature trees can survive much longer, the first sign of infection being the reduction of foliage on the extremities of the branches. Over several years, the infection spreads, eventually killing the tree.

There are,at least,three billion deciduous trees in the UK and, before infection hit, ash was amongst the most common, along with birch and oak.Ash dieback affected the southeast first, with a kill-rate of around 80%, and slowly moved north.

As a statutory authority, Redcar & Cleveland Borough Council has an obligation to ‘abate risk and hazards’ to the public. In practice, this means that RCBC will have to monitor, fell and dispose of thousands of ash trees throughout its own land, especially on highway margins. It could cost RCBC up to £3m over the years, just to deal with the ash trees for which it’s directly responsible. In addition, the council has the duty to require other landowners to deal appropriately with their own ash trees where they pose a risk to the public. Once required by the council to act, neglect to do so will result in RCBC doing the necessary work,then recharging the owner.

The cruel irony of ash dieback is that, to combat global warming by carbon capture, we need more trees. Of course, the council plants whips and saplings every year but, just to replace the doomed ash trees on council land, will require the planting of at least 20,000 trees, mainly hardy birch and acer (maple family, including sycamore). Eventually, it may be considered safe to plant East European ash, which, over the decades, have built up resistance to dieback. Recently, a large, infected ash was felled by the council’s contractors, Oakdale (NE) Ltd.,on Moorsholm Recreation Field and, sadly,at least another three are programmed to follow. Of course, they will be replaced by other species in appropriate positions. In Lockwood ward, this is just the beginning. The many ash trees along public highways will have to be dealt with, as will those on public open spaces, like Lingdale’s expansive and attractive Wildlife Meadow, the site of the former shale heap.

A sad and worrying infection, for our countryside, our planet and ourselves.