‘Felling this forest would be like knocking down a cathedral’

An ornithologist cradles a nuthatch in his hand as the low December sun throws the stark winter canopy of trees into relief.

Frost-covered leaves crunch underfoot along a path which meanders through ancient oaks, sycamores and willows. It is fringed with wood piles playing host to multiple types of fungi. Buzzards swoop overhead and birdsong fills the air.

This 3.2 hectares on the Northamptonshire/Warwickshire border has been woodland since the 1600s when James VI was on the throne. It is a breeding ground for many British birds, including tawny owls, woodpeckers and the now globally-at-risk marsh tit, willow tit and woodcock. As such it qualifies as ancient woodland, a unique and now increasingly threatened habitat in the United Kingdom.

Walking through Glyn Davies wood, Luci Ryan, lead ecologist for the Woodland Trust, points to the pink flags marking out how the HS2 rail link will – if the railway goes ahead – tear apart this old English woodland. Her job is to try to save not just Glyn Davies wood, which is owned by the Banbury Ornithological Society, but more than a thousand other ancient woodlands in the UK from the relentless encroachment of development.

“Ancient woodlands are an ecological goldmine,” said Ryan. “They are the most biodiverse habitats in the UK. They are uniquely British, and part of our heritage. They are our natural cathedrals, and cannot be replaced just by planting trees elsewhere. It is like knocking down St Paul’s Cathedral, putting the pile of bricks somewhere else and trying to say it’s the same thing.”

Increasingly, the UK’s ancient woodland is being lost to housing or industrial developments and transport links, and protecting these incomparable habitats makes up much of the workload of the Woodland Trust, one of four charities supported by the 2019 Guardian and Observer climate emergency charity appeal. The trust’s job has never been tougher; 1,064 ancient woodlands are currently under threat across the UK – the highest number since the trust’s records began in 1999. Since that year, the campaigning work of the trust has saved 1,101 from destruction, while 800 have suffered loss or damage. “It is deeply frustrating,” said Ryan. “Ancient woodland only covers 2.4% of the UK, so you would have thought it could be avoided. But that isn’t happening.”

The trust supports a team of 60 volunteers across the country who act as an early warning system. Known as the “threat detectors”, they scour planning applications for any sign of woodlands at risk, and pass details on to Ryan and the campaign team at the trust.

In the last seven years, it has been the Goliath of HS2 – created through an act of parliament rather than the normal planning process – which Ryan has been up against. The planned railway link between London, Birmingham, Leeds and Manchester will destroy or partially destroy 108 ancient woodlands covering 56 hectares of land.

Tenacious campaigning by the Woodland Trust has managed to save 14 hectares of ancient woodland, mostly by persuading ministers and HS2 of technical solutions – including tunnelling – to avoid desecrating the woodlands and the soil habitats within them which have been untouched for 400 years.

The trust also protects woodland through the purchase of areas which are threatened. Their sites range from ownership of a hedge in Sherborne, Dorset, to Loch Arkaig, a Caledonian pine forest in Spean Bridge, and Ben Sheildaig, a mountain in the west Highlands, which they purchased earlier this year.

Decades of pressure by the trust helped to change the national planning framework, which sets out the government’s planning policies for England. It now states that any development resulting in the loss of ancient woodland or ancient and veteran trees must be refused unless wholly exceptional.

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In Harrogate Keith Wilkinson, a trust volunteer, was among an army of campaigners who fought successfully to save dense ancient woodland covering the steep sides of Nidd Gorge, where the River Nidd enters a deep ravine, from the bulldozers clearing land for a relief road.

A combination of high-profile marches attended by hundreds, and petitions thousands strong, finally reaped rewards when North Yorkshire county council withdrew the relief road project in October.

“For a fairly modest charity, with a small staff, trying to cover the whole of the UK, the Woodland Trust is amazing,” said Wilkinson. “They are tenacious. They are the protectors of the country’s woodlands.

In the fading light at Glyn Davies wood Helen Franklin, from the Banbury Ornithological Society, completes the ringing of blue tits, nuthatches and other birds – part of the society’s work to closely monitor population changes and movement.

Remembering the moment that the threat from HS2 was confirmed, Franklin is emotional. “I burst into tears. It is heartbreaking,” she says. “There is no logic to it and it makes me angry and deeply frustrated.”

There remains a glimmer of hope that the wood may be saved; its fate rests on the whim of a new government, even as the diggers wait a few feet away in a siding.