ASH die back is a devastating disease affecting the UK's native ash trees. Latest research suggests that less than one per cent of the country's trees will be resistant.

Victoria Benn, membership and events officer for environmental campaigning charity, Friends of the Dales, based in Gargrave, looks at the devastating disease, the impact it is having on local nature reserves, such as Grass Wood, Grassington, and what people can do to help.

THE Yorkshire Wildlife Trust looks after more than 100 reserves across Yorkshire, including 12 in the Yorkshire Dales.

It’s a set of figures which adds up to the trust knowing a thing or two about conserving, protecting and restoring wildlife habitats, as well as about the issues and challenges they face.

For these reasons, Yorkshire Dales environmental campaigning charity, Friends of the Dales, invited Graham Standring, the trust’s living landscapes officer to host one of its regular monthly ‘open to all’ digital talks.

As a small charity at the forefront of campaigning to protect the Dales, we take a stance on many issues including affordable housing, rural bus services and biodiversity.

Our free monthly talks, along with our quarterly magazine, enable our members – and non members – to engage directly with conservation experts who know the reality of the Yorkshire Dales landscape first hand.

Despite Graham’s talk celebrating some important success stories for the YWT, such as the wild flower and fauna rich ‘Ashes Pasture’ near Ingleborough, one of the standout aspects was the opportunity to find out more about the very serious issue of ash dieback which is affecting large numbers of trees across the Dales, in particular the trust’s reserve at Grass Wood, near Grassington.

One of the largest areas of broad-leaved woodland in the Dales, Grass Wood is also designated a Site of Special Scientific Interest (SSSI) due to the diversity of plant and animal species it supports, from bird’s nest orchid, horseshoe vetch to tawny owls and the northern brown argus butterfly – a species that has declined by over 50 per cent since the 1970s.

“Grass Wood is 78 hectares, so it is a big, predominantly ash woodland growing on a series of limestone terraces,” says Graham Standring. “Yet since 2016 it has been terribly and noticeably affected by the chronic fungal tree disease, ash dieback, with more than 95 per cent of its ash tree population now dead or dying.”

An air borne fungal disease, ash dieback prevents the tree moving liquids up and down its trunk. Visible infection symptoms include leaf loss, crown – the leafy canopy of the tree – dieback and bark lesions, which directly and indirectly lead to the death of the tree.

Current research warns that less than 1 per cent of the UK’s native ash trees will be resistant to the disease, an impact which will be devastating.

To prevent infected trees becoming a danger to the public, a vital measure as the trees become very brittle once the disease takes hold, the YWT has been granted a felling licence to fell and remove those trees with more than 50 per cent die back in their canopy that are within ‘falling distance’ of the public footpaths, road and main track through the wood.

Those local to Grass Wood will no doubt have been aware of the vast quantity of orange dots marking out the trees to be felled a year or so ago, although it is important to emphasise that in all other areas of the woodland the aim is and has been non-intervention, leaving dead and fallen ash trees as a good habitat for other wildlife.

“Another reason for leaving those trees that don’t pose a danger to the public is that there is a slight hope that some of the trees might develop a genetic resistance to the fungus,” explains Graham.

“DEFRA’s Living Ash Project’s seed bank are collecting and analysing seeds from existing trees for signs of tolerance to the disease, but unfortunately there is no evidence of this yet.

“The only glimmer of positive news is that as the felling has progressed, glades have opened up within the wood, which has encouraged new species of wildflowers to grow and flourish, such herb-paris and marsh valerian.

“Butterfly species, speckled wood and brimstone have also become much more proliferate and noticeable.”

As laid out in its Forestry and Woodlands policy, Friends of the Dales is actively supportive of the work carried out by partner organisations, like YWT.

In order to protect the biosecurity of our ash woodlands, the trust is urging people to report sightings of healthy ash trees in a woodland setting to the Living Ash Project via its ‘Report a Tree’ link at: livingashproject.org.uk/the-survey.

It’s a small but important action that people can take to help mitigate the effects of this terrible disease.

The Living Ash Project can then collect seeds for testing and potential future regeneration. The best time to look out for healthy ash trees is right now and throughout the summer, when it is possible to make as assessment on crown health. Even trees showing up to 25 per cent crown dieback should be reported.

Diseased trees can also be reported to :www.observatree.org.uk

For more details about Friends of the Dales, visit: www.friendsofthedales.org.uk