Copyright

4th Estate

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This eBook first published in Great Britain by 4th Estate in 2018

Copyright © Lisa Samson 2018

Cover photograph © plainpicture/Bildhuset/Bengt Olof Olsson

Design: Ben Gardiner

From Swimming in the Flood by John Burnside published by Jonathan Cape, reprinted by permission of The Random House Group Limited © 1995.

While every effort has been made to obtain permission to use copyrighted material reproduced herein, the publishers will be glad to rectify any omissions in future editions.

Lisa Samson asserts the moral right to be identified as the author of this work

A catalogue record for this book is available from the British Library

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Source ISBN: 9780007544615

Ebook edition: March 2018 ISBN: 9780007544622

Version: 2018-02-15

Dedication

For Mike, without whom this book

wouldn’t have been possible

Contents

Cover

Title Page

Copyright

Dedication

Introduction

The Blight of Ashwellthorpe

The Science behind Ash Dieback

Secrets

Bread

Ancestors

Ash Fires

Life Cycle

Spring

Isolation

Shadows

Shelter

Resistance

Notes

Acknowledgements

About the Author

About the Publisher

Introduction

You may walk past the ash – its slenderness and height blend easily into any wood or hedgerow – but in spring you’ll stop to admire the bluebells shimmering in the light that filters through its foliage. The continued existence of the ash tree is under threat from Ash Dieback, a disease that has spread from the Continent and is threatening ash trees in Britain. During the research and writing for this book, I was diagnosed with a benign brain tumour, which changed my life irrevocably, never to be the same again. Epitaph for the Ash is a celebration of the ash and an account of my personal journey as I recorded its decline over the last few years, taking the reader from the lowlands of Norfolk to the uplands of Yorkshire, and from Devon to the northernmost reaches of the British Isles. The book explores the cultural significance of the ash tree, tracing its mythology in Norse culture and through some of the literature on and history of woodlands in Britain.

The ancient woodlands of today are a fraction of the size they were in Anglo-Saxon Britain, as agriculture and industry have gradually encroached on the forests. During the post-war years thousands of acres of woodland were given over to agricultural production or buildings to accommodate a burgeoning population. As the elms were ravaged by Dutch Elm Disease in the latter half of the twentieth century, the importance of the ash as a habitat for rare flora and fauna increased. Trees, like any living organism, have always suffered from blight and disease, but the loss of most of our elms, and now the danger to the ash poses a serious environmental threat.

In May 1978, I clearly recall my mother bristling with pride as she showed me a copy of the Sunday Times Magazine, which featured my uncle’s new book, Epitaph for the Elm. Gerald Wilkinson was her older brother, the eccentric tree expert. We saw little of him, but occasionally he would stop by in his old Volkswagen camper-van on his way to or from one of his extended research trips in the woodlands of Britain. To a town child like me, with a yearning for the open countryside, this seemed the most romantic way to spend your life, and I’m sure I begged him to take me with him.

I’ve been communing with trees since I was young and sometimes fancy they are aware of me. The brightest days of my childhood were when my family and I got onto a bus into the countryside, then walked through the woods and fields, picnicking under a tree. I’d roam away from the others and listen to the trees whispering. I never wandered too far because I was afraid of my own shadow and would imagine danger lurking behind hedgerows and in the depths of the dark wood. I’ve always loved trees for their swaying limbs and shady canopies, so easy to draw, but it is only as an adult that I have learned to regard them as friends. They’re good company and they do talk if you stop to listen.

I was too young to understand the full impact of Dutch Elm Disease, but as I grew up and my own interest in trees deepened, I often referred to Gerald’s books. His death in a car crash in 1988 fuelled my intention to learn more about his obsession with them. Now, nearly three decades later, it is predicted that Chalara fraxinea, the fungus that causes Hymenoscyphus fraxineus or Hymenoscyphus pseudoalbidus – Ash Dieback – will ravage the ash trees, again changing Britain’s landscape. It was found in the wild in Britain in 2012, in Ashwellthorpe, Norfolk, and since then it has spread relatively quickly, with new cases reported often in the press. My home county of Yorkshire will seem barren without the ancient ashes protruding from limestone scars and chalky cliff faces, or spreading their fine canopies over the hedgerows.

The ash’s status as a ‘magic’ tree with healing properties gives it a fascinating history. Gerald suggests that in Neolithic times ‘the Ash may have been sacred’. Druids regard it as such, and in Norse mythology the ash was the Tree of Life, the most important living thing besides humans. It is one of our strongest trees, used for framework in vehicles and tool handles, but craftspeople and manufacturers are already using other materials.

Across the length and breadth of Britain place names are associated with the ash – Ash, Ashburton, Ashby-de-la-Zouch, Ashbourne, Ash-cum-Ridley, Ashover, Ashwater, Ashtead, Ashkirk, Ashcot, Ashwell – anthropological mnemonics linking people to their places. Some will have been named after self-sown ash seeds that blew on the wind, others for the ash their inhabitants cultivated, but all bear testimony to the part the ash has played in our civilization.

The Blight of Ashwellthorpe

My first view of Ashwellthorpe is of a bright yellow rape field where poppies blush under a louring sky, June, 2013. The wood comes into view, ‘a darker green than usual’, like the Enchanted Wood of Enid Blyton’s books. It is dense with many species of tree. In rich full leaf, they nod and sway in the dull light, waiting for the rain. They beckon to me over the hedgerows and houses, but the road running straight through the village leads me past. I nearly hit the kerb as I try to glimpse the ashes I’ve come all this way to see. An elderly cyclist ahead of me pauses to let me pass, perhaps to save himself or to stare at me, a stranger in this sleepy village. I pass the hall and the church, the rows of plain houses and cottages that line the road: a barrier obstructing my view of the wood.

The village sweeps by and I pull up in the lane beside three ashes that all have the characteristic antlers of leafless upper branches, like oak trees widening their canopy as they mature. Crown dieback is a symptom of Chalara fraxinea’s presence and these trees remind me of photos I’ve seen of diseased trees in Poland. It could be part of a natural process … or signs of Ash Dieback. Naturally, I go for the latter theory since I know it has spread widely across the Norfolk Broads.

I climb out of my car and look back at the village and the wood. It is low-lying, cradled in the embrace of the fields and village that have depended on it for centuries. There is a gap between a larger and smaller patch of woodland, mown through as straight as a Roman road. The smaller wood is Upper Wood and the larger is Lower Wood. They are believed to have been separated during the Napoleonic Wars in the early 1800s, when a perfectly straight line of vision was required between London and the Norfolk coast for semaphore messages to be relayed as part of an early-warning system. Apparently it took only half an hour to relay the message of an approaching ship near Great Yarmouth all the way to London. Upper Wood is now privately owned and is a jealously guarded pheasant-shoot, but Lower Wood is managed by the Norfolk Wildlife Trust and is a site of designated specific interest. It is also the first place in Britain where symptoms of Ash Dieback were discovered in the wild.

The woods are beckoning to me. I fancy I can hear them whispering their secrets, like the trees in The Magic Faraway Tree. Blyton’s enchanted tree is huge and guarded by fairy folk, its branches reaching into different magical worlds. Its roots stretch far into the earth and it represents a complete entity, both admired and feared by the woodland folk who live nearby. Although the Faraway Tree is of an unspecified type, Blyton was perhaps aware of the ash’s magical properties and its powers of protection. It bears some resemblance to Yggdrasil, a huge tree that was at the centre of the Norse universe. Its roots were so abundant and so long that they reached into the underworld, and its trunk was so tall that its branches stretched to Heaven. Yggdrasil was the giver of life, at the beginning of all creation.

I drag myself back into my car and drive on to Norwich, knowing I will return in the late afternoon. Being among green things, in nature, is almost as essential to me as breathing: I cannot go too long without it. I need to feel the air, sun and rain on my face, to hear the wind blowing through the trees and grass. With a pang, I watch the woods receding from view and just refrain from stopping the car to go back.

It’s pouring with rain when I turn into the tiny Rosemary Meadow car park in the late afternoon. Steve Collin, head forester with the Norfolk Wildlife Trust, has to flag me down. No bigger than a garden, it backs onto the Wildlife Trust Meadow that skirts the south side of the wood. It is bright with Greater Spearwort, like large buttercups, and tightly clustered Red Clover, but today the grasses hang their heads, beaten down by the rain, which has been gathering force all afternoon. Steve seems not to notice it as he squelches towards the wood, with me slithering behind. He is at home here and strides with an air of propriety, accustomed to leading people round the wood that has received so much media attention in recent months.

The dripping trees enfold us in their shadows, sheltering us from the worst of the downpour. Fat raindrops splay on my glasses and blur my vision as I look up to the top of the canopy to see the tall ashes that have shot above the roof of the wood in their eagerness to reach the light. At my level, five feet four from the ground, it would be easy to walk past the trunks of the young ash without noticing what they are, since their bark is darkened with damp. They sway in the gloom of the wet wood, their leaves rustling, sweeping away the rain.

Twigs snap underfoot as branches of alder and ash brush our legs and reach out to touch our shoulders. A short way into the woods, we stop by what is probably the most photographed tree of 2012: the ash sapling on which Steve first noticed signs of disease in October that year. It has a diamond-shaped lesion close to a shoot some way up its thin trunk, which is seeping resin, like congealed blood from an open wound. Unlike human flesh, though, the tree bark cannot heal. Steve breaks off a dead shoot to show me how brittle it is. The effects of Chalara are easier to spot on a thin young tree because the diseased girdle that forms around the trunk is visible and everything above it dies. Leaves have blackened and twigs have wilted, ready to fall to the ground, no use to anyone. Most of the dead leaves and wood are removed once they’ve fallen, as instructed by the Forestry Commission.

On the day they first spotted the disease, Steve Collin and Dr Anne Edwards, the volunteer warden at Ashwellthorpe Woods, were looking at the coppicing that had been done. After twenty years, they had finally brought the cycle of coppicing into a regular rotation and the woods were responding to their care, with an annual increase in the numbers of bluebells and wild orchids that would not thrive as well without the light exposed by coppicing. Steve and Anne noticed that some of the trees appeared to be dead and reported it to the Forestry Commission, suspecting an invasion of Chalara fraxinea. Meanwhile Anne, a scientist, took samples back to the John Innes Centre where she works and alerted her colleagues to the potential danger lurking in their own backyard. Within weeks Chalara was confirmed but they knew they wouldn’t be able to gauge the real level of damage until the autumn leaves had fallen and the new buds had unfurled on the trees in spring. We discuss whether the fungus was blown in spores across the sea from Denmark, and Steve notes that the wind has been blowing easterly for a few years. In addition, the heavy rains in recent summers made perfect breeding ground for the fungus, although the ashes themselves can thrive in wet conditions.

An area of saplings holds yellowed shoots that have been drained of life. A bright yellow one is still sprouting from the base, though most of the tree above the infected girdle is dead. It hides behind a group of healthy green shoots. The saplings’ bark is slick with rain that trickles over a purplish gash, the mark of disease. Most of the signs of Ash Dieback in Ashwellthorpe are in the coppice growth, but the big ashes at the back of the coppice have Ash Dieback at the top and have probably had it for two or three years at least. The rooks perched on the uppermost branches are oblivious, croaking to one another in the dark heart of the wood.

Ash is the predominant species here but it is a mixed coppice of hazel, ash, hawthorn, alder and sallow. Ash, closely followed by alder, was possibly the commonest tree to make up the forests of the Neolithic wildwood that covered the Broadlands when the sheep of Neolithic peoples began to nibble at the tasty bark and seeds, turning the woods to scrub. Much of the woodland would have been felled to make way for farming and building. By the time the Anglo-Saxons, and later the Vikings, arrived, the woods were shrinking, with fields taking over. The Domesday Book of 1081 makes reference to a large tract of woodland here, and the present day Ashwellthorpe Woods are the last vestige of its former dimensions. The woods have retained their current size since about the 1830s. Seen from above on aerial photos, they form two darker blocks of green among the patches of yellow cereals, pale green wheat and brown ploughed land.

Behind Ashwellthorpe Hall, to the east of the wood, the remains of an Anglo-Saxon burial site were found, so it is safe to assume that there has been a settlement here since the early Anglo-Saxons arrived between AD 500 and 700. The Angles, Saxons and Jutes, who came to East Anglia in search of a better life, would in all probability have approached Ashwellthorpe (then unnamed) from one of the tributaries of the Waveney river, which then reached nearly to the sea in the south. The dark ash wood would have risen from the lush marshlands and mud banks, a welcome sight on the terraqueous landscape, providing shelter and respite from the sun. Anglo-Saxons tended to live in isolated farmsteads of one or two family groupings, eschewing the larger towns and fortresses founded by the Romans in favour of a simple rural life.

Lower Ashwellthorpe Wood has an industrial history that dates back centuries, serving the local communities with faggots, hurdles and poles. We pass a group of ash that has grown in straight lines and would make strong, flexible poles, essential if you were going to build a structure of any kind. The Farming Journal of Randall Burroughs provides evidence of the various uses made of Ashwellthorpe Wood. Burroughs was a gentleman farmer from Wymondham who maintained a log of his daily business that is of little literary interest but of great historical value. We can connect the ash trees of Ashwellthorpe Woods with Burroughs’s regular acquisition of hurdles. On Monday, 21 February 1796 he states: ‘Fetched a load of hurdles from Ashwellthorpe Wood for Wm Gray.’ Gray was clearly a local veterinary surgeon, or someone who assumed the function of one, because on Sunday, 24 February 1799, Burroughs wrote:

On Wednesday Nelson went to Ashwellthorpe Wood for a load of hurdles namely 3 dozen & deposited them in the 12 Acre. On Thursday to Wicklewood & borrow’d 3 doz gate hurdles of Mr Bernard. On Friday the ewes and lambs viz 46 ewes, 49 lambs & 21 wethers were hurdled upon the 12 Acre. The lambs had been gelt on Tuesday by Wm Gray. The night was very rainy but they all recovered without ointment.

The hurdles he purchased were almost certainly made of ash and were used traditionally to hold livestock in place for routine operations, such as neutering or shearing. It is an example of how ash from these woods has served the needs of the farming community and advanced their interests.

Prior to the Norfolk Wildlife Trust’s acquisition of the wood in the 1980s, it had been owned and worked by the Co-operative Society, which coppiced ash poles for broom handles and hazel brush for their heads. For centuries until the 1970s a brush factory in Wymondham obtained all its ash poles from Ashwellthorpe Woods. It employed many local women, who were highly skilled and worked for half the wage that men received. The Victorian historian William Kiddier recorded an ongoing battle that began in 1829 when male journeymen complained that the women were undercutting them. Kiddier laid the blame at the feet of the employers for exploiting the women, who were often so poor that they were simply glad of the work to support their families and did not dare to quibble over their pay. There is now a museum of broom-making at the former factory in Wymondham, which describes the plight of the local women who worked there for generations.

Lower Wood still has the feel of a working wood, with one well-trodden path in a regular shape, as if it was marked out by lines of coppicing and collection; there are few of the smaller tracks that children make in woodlands used for leisure. The clumps of thick, taller ashes seem impenetrable: the trees seem to have closed ranks, as if to prevent human foraging. Perhaps it is their response to the over-exploitation of centuries of industry, or maybe they are hiding the signs of Ash Dieback that are evident in their bare crowns. Steve Collin knows of trees in Norfolk that started showing signs of incremental growth loss six years ago but at the time no one realized what it was. That particular plantation has completely succumbed to the disease.

At Lower Ashwellthorpe Wood, there will be one final harvest of the timber that can be sold for firewood, when the dead trees are coppiced and removed in the cycle of woodland management. Once the infected ash has been coppiced it won’t grow back, and infected timber can’t be used because the disease stains it. Steve was advised by European experts to fell any ash the instant he saw wilting leaves, so that he could sell the wood before Dieback took its full effect. He wonders whether that was what happened on the Continent, whether foresters felled the trees with Ash Dieback at the first sign of the disease so that they could still make use of the wood. Such radical action would be detrimental to the ecosystem of a wood such as Ashwellthorpe, where removal of the dead wood from a forest floor with easily compacted soils and wet conditions would also take away the fungi and flora attached to it.

There are many schemes around the country, funded by the Forestry Commission, to burn wood as an alternative to fossil fuels but they were based on the reliability of ash, which stores well, grows fast and burns better than any other wood. The ash coppiced from Lower Ashwellthorpe Wood would have enabled the woodlands to pay for themselves. Now Norfolk Wildlife Trust will have to find other sources of fuel, which may mean buying in from abroad. This would not only be expensive but potentially fraught with hazards, such as the fear that the lethal Emerald Ash Borer from America, where it has laid waste to millions of ash trees, could somehow find its way across the Atlantic.

We pause for a moment to watch a furniture beetle and a Minotaur beetle, distinguished by its horns, crawling towards a hole in an ash, as if in a race against one another to get inside it first. The hole is almost as big as the backside of a cow and the bark has peeled back to form a thick fringe framing the exposed wood, which is gradually rotting, aided by the beetles and other insects that feed off the bark. Steve picks off the furniture beetle to show me but it walks off the end of his thumb and falls into the grass: we have inadvertently helped the Minotaur beetle to win the race. Certain epiphytes, like lichen, prefer the ash bark because oak is too acidic and there is a danger that many such rare species will be lost unless they find alternative habitats.

Under the tree a mat of ground cover sends its leafy runners in all directions – it stretches right across the path. This is Ground Ivy, or ‘ale hoof’, as the early Saxon and Norse settlers called it. The leaves are very different from those of ivy, larger and rougher, with teeth all the way round. I rub one between my thumb and forefinger and smell it: it has a tart citrus flavour, a little like the lemon sage I grow in my garden. Apparently it was used as an alternative to hops for making beer, and the Scandinavian Vikings, who lived near the wood, would almost certainly have used it to make a fresh light ale. It likes damp places and semi-shade, so the foot of an ash is the ideal place for it; its purple flowers cling to the ivy, each with two lips to drink the rainwater. It is likely that when the Vikings dug it up they would have used spades with ash handles.

Before leaving the wood, I stand still to look up at the canopy of a few mature ashes growing so close together they probably share the same stool under the ground. Some of their branches interlock but their crowns fan out into finely etched sprays, each leaf like a black flower, hundreds of them dancing under the raindrops that tickle my skin. Speckled light filtering through the leaves almost makes me dizzy: the overlapping sections of the canopy seem to revolve, like a kaleidoscope turning. A nearby broadleaf tree, probably a sallow, forms a solid clump of closely knit leaves in its canopy; a morris dancer next to a ballerina, it is lacking in elegance and lets no light through.

The morning after the rain, the clouds gradually clear, giving way to blue sky and warm sun: a perfect English summer’s day. My friend Lizzie and I walk away from the village towards Underhill, slightly uphill but not so that you’d notice. The farmer has cut a path that takes us straight across a corn field. Wheat ears brush against our legs then spring gracefully back into place. The earth is soft and sap rises through the grasses as the moisture of the night’s drenching evaporates on the warm air. Miles of cereal fields are spread all around us, relieved only by hedgerows and distant houses. A skylark is singing above, and I turn to see the wood behind the village. The plain houses of Ashwellthorpe have receded from view and it is easier now to imagine the wood as it once was, surrounded by the fields and marshes of the Anglo-Saxon settlement.

On our approach to the solid cluster of houses that forms the hamlet of Fundenhall, the fields that scroll away from the woods, with the marks of previous inhabitants imprinted on the soil, are used to human feet. The early Anglo-Saxons, when they arrived from their cold wastelands, must have been seduced by the warm climate and fertile, waterlogged land. We are walking in an anti-clockwise direction: south-east to Fundenhall, north-east towards Toprow, north-west to Wreningham, then south towards Lower Wood. From every angle I can see the wood. It is the dominant landmark in the area, the nucleus around which everything else has grown – fields, hedges, paths, roads, farms and houses, people and animals. In a landscape where hills are absent, birds of prey perch on the highest trees (probably ash) to survey the surrounding countryside for voles and mice.

The wood is about a mile to the west as we walk by a high hedge at the side of another neat field of corn. By the end of this walk we will have seen it from south, east and north. Between us and the wood, hidden under layers of earth and crops, the Anglo-Saxon burial ground lies behind Ashwellthorpe Hall, invisible now among the tranquil expanse of fields. Another skylark is singing above us, and the scents of flowers are delicate and sweet. Yellow Field Pepperwort, red Sheep’s Sorrel and Elderflower waft across the golden waves of wheat. My excitement grows at the prospect of walking in the wood again. It is hot now, well past midday, as we cross the corn fields towards Lower Wood. Although I was in it less than twenty-four hours ago, I am eager to see it in sunlight.

A row of ash and alder guard the north side. They have been here longer than any other species. We are entering by a path where tall grasses have been trodden down and the sides of an earth mound have been sculpted by the weight of many feet. Lizzie is slightly ahead and pauses to look around. In black T-shirt and shorts, she is framed by an ivy-smothered trunk and a mature ash, almost hidden under the burgeoning mass of vegetation rising above her. She looks slighter than usual and, fleetingly, as she slips into the waiting wood, she seems like a tree wraith or a wood nymph.

An ancient bank, with a ditch, surrounds the wood on all but the west side, where Lower Wood was separated from Upper. The ditch, now rank with stagnant water, would have been deepened by farmers over the centuries to deter livestock from entering the woods, but the original bank is believed to have been created in the Anglo-Saxon period. The ditch would have been dug with ash-handled spades, labour-intensive work. The farmers and peasants who toiled over it are most likely under the soil in the burial ground I mentioned.

When the ash trees have all gone, the mound will be exposed. Nothing is ever planted in this wood. The ‘Ash’ in Ashwellthorpe will be a historic reference. The ‘well’, originally ‘weall’, meaning ‘bank or mound’ in Anglo-Saxon, will remain: a lip of mud sculpted over fifteen hundred years. It will continue to accommodate the rain and silt and keep the boundary of field and tree. If the bank could talk, it could tell us who made it and why, tales of the many people and animals who have passed over it and left. When the ash trees have gone, the bank will be the sole keeper of the woods.

The earthworks will do the job they were originally intended for: to delineate the woods from the farms and maybe as a form of defence. Perhaps they were decorated with spikes or sharp implements to impale robbers and marauders crossing the woods to raid farmsteads at dead of night. Protection was much needed in the long and turbulent period of the many Viking invasions of the eighth and ninth centuries before the Danelaw was established. It seems likely that the Anglo-Saxons conceived the earthworks as part of a defence system, as they were in other parts of the country. It was common practice for earth mounds to be built around settlements as defence boundaries.

The copse is cool and welcoming after the heat of the open fields, the air heavily scented with the humus of rotting vegetation and moisture-locked soil. A little light filters though the fine canopy of ash and sallow, but not enough to dry out the wood after the drenching of the last few days. Rays of sunlight sparkle on the woodland floor. Last night the branches were dripping and bent under the weight of rain; today the boughs of the ash are still heavy and there is a sombre air among the trees. Our mood changes as we walk through them, looking for lesions on the bark of young ash. At first it is a game to try to spot the signs and I’m keen to show off my new knowledge. But Lizzie is walking fast ahead of me, and doesn’t want to stay too long to examine the diseased trees. We become silent, and I feel as I do when visiting a sick relative or friend in hospital: I want to stay and cheer them up but feel helpless.

We leave the wood to the plaintive whistle of a chiffchaff, the two notes, one higher than the other, seeming to call us back. As we stroll past the meadow towards the car, I’m aware of the trees whispering behind me. I turn back, but the sound fades. Yet as I drive away from the village, with the windows wound down, I hear it again, many voices muttering, not words or syllables, but musical notes. It reminds me of the description of the spirit chorus that the soul seers claimed to hear in Montaillou, France, in the fourteenth century. Many occupants of this wood are passing into spirit form and, clamour as they may, nothing can save them.

In my rear-view mirror, the dark body of the wood recedes from view, like a rain cloud passing by. I notice more ash with exposed antler branches and think of the many that will fall victim and die on the roadsides over the coming years.

The Science behind Ash Dieback

People up and down the country are becoming more aware of the plight of the ash and, in an area outside Norwich, scientists are working to halt the progress of Chalara fraxinea. The John Innes Centre was set up as a charity in 1910 by John Innes, a landowner and entrepreneur from London, and has since been established as a centre for plant science and microbiology of international repute funded by the Biotechnology and Biological Research Council. The original buildings date back to the 1960s, when the John Innes Centre moved to Norwich, and the newer buildings have clustered around them in regimented designs of varying styles. If I didn’t know better, I might have thought I was on the edge of a housing estate in London’s Peckham or Brixton. When I walk across the car park on the same day in June that I visit Ashwellthorpe, I see that the buildings are softened by grass and a few clumps of trees.

Dan MacLean greets me in the reception area and walks me through a pleasant outdoor garden to the laboratories. They are empty, and looking through the glass wall makes me feel as though I’m being shown an exhibit in a museum. I remember as a child going round a futuristic exhibition at London’s Design Museum of domestic life in the twenty-first century. The laboratories are a bit like that: high metal contraptions and long melamine tables, all very clinical. In fact, they resemble characterless kitchens, which need a few dirty plates and a fruit bowl to make them real. I can see four, each visible to the rest through glass panes, lending them a competitive edge – I imagine young scientists coming to show each other how it’s done. At the far end, there is a flat-fronted grey machine, called an athemizer, where samples are frozen so that they break down into tiny particles or strands that can be analysed. There are little bottles, too, covered with tin foil, filled with transparent brown liquids.

The John Innes Centre is at the forefront of the fight against Ash Dieback. Daniel MacLean works for the Sainsbury Laboratory as a bio-informatician. He analyses DNA sequences on a computer. Ash trees are famous for distorting the division between male and female because they can be hermaphrodite, and a few are. They are often thought to be wind-pollinated because they do not produce petals or sepals and the flowers appear before the leaf grows. Pollen is a kind of plant sperm that is often carried by bees or other insects to mix with female structures. When greatly magnified, electron micrograph scans of pollen grains show them to be like circular pumice stones with tiny holes. They are pale yellow in colour and cluster together. When a tree trembles, its pollen forms a visible haze. Unlike the female trees, males do not produce fruit or seeds. The flowers of female parts on ash trees are purple and grow into seeds attached to ‘keys’ – so-called because they resemble old-fashioned keys. They turn rapidly in the wind and are also known as ‘spinners’. Like humans, each ash will be unique but will share common characteristics.

In the autumn of 2012, when Ash Dieback was first found in the wild in the UK, Dr Anne Edwards, who also works at the John Innes Centre, took a piece of wood from a sick ash tree in Ashwellthorpe Lower Wood to the centre. Other scientists there took a DNA sample from it and confirmed that it contained the pathogen Chalara fraxinea. A cross-section of wood with Ash Dieback shows what resemble ink blots on top of the concentric rings. Windblown spores of Chalara fraxinea infect leaves. The fungus grows down the leaf stem and into the core of the tree. Trees with Chalara fraxinea are more susceptible to other pests and pathogens, such as Armillaria fungi or honey fungus.

Research into Ash Dieback aims to find out how the pathogen is getting into the trees. The work has been accelerated by the use of crowd sourcing, which enables people from around the world to make contributions. Whereas before Dan would have had to prepare a paper and wait for a conference, through crowd sourcing, or publishing results straight away, he receives feedback almost immediately. He is helping to build a map of the areas in the ash genome – the complete set of genes present in each cell of an organism – where susceptible trees differ from those that are resistant. Dan is a member of the Nornex Consortium, headed by Professor Allan Downie, leading the investigation into Ash Dieback, made up of various partners, which include the Sainsbury Laboratory, the universities of Edinburgh, York, Exeter and Copenhagen, Forest Research, the Food and Research Agency, the Genome Analysis Centre, and the Forest and Landscape Institute, Norway. Nornex Group scientists are working with Danish scientists who identified the so-called Tree 35, which has low susceptibility. If they can identify the unique genetic features that reduce its chance of being infected by Ash Dieback, it will help them to breed an ash resistant to Ash Dieback in Britain. Perhaps the tree contains an enzyme that inhibits the disease. Maybe its bark is thicker. They are trying to find the answers to these questions because Chalara fraxinea is such a virulent fungus.

Identifying resistant trees could speed up the process of replacing those ashes that will probably die of disease. In their search for sources of resistance, the task of scientists at the John Innes Centre and Sainsbury’s Laboratory is made harder by the fact that there is almost free movement of plants: our border controls expose our native plants to exotic diseases because security is less tight than it should be. Dan confirms that saplings are grown in Europe then brought to these islands, which makes it difficult to monitor their provenance.

Early in August, Dan and his colleagues release the ash game Fraxinus on Facebook. In its first six months it attracts an overwhelming number of players, who score points by putting together sequences of coloured leaves on their computer screens, matching them to genetic data that scientists working on Chalara fraxinea have found. Scientists may use the data the game produces to help analyse the susceptibility of a certain tree to the disease or to probe genomic DNA.

At the end of August 2013, Antony Milek, a student, sets up a vigil to guard an ash just over his garden fence in Kitson Hill Road, Mirfield, in West Yorkshire. It is in danger of being felled because the rest of the mature trees close to it, nearly thirty altogether, have gone: workmen believed that permission had been granted for the land to be sold to developers. He attracts the attention of the local papers, who report on his activities. Antony sits in the shade of the tree, which has been there all his life, at the bottom of his garden: as he is so close to it, the workmen cannot risk felling the tree. The land in question was once a refuge for birds and small mammals. The ash towers over the fence; it has two trunks, and appears to be in perfect health. A protection order should have been placed on it because Chalara fraxinea threatens ash trees.

On 5 June in Arkon, Ohio, a woman is arrested for sitting in an old ash tree that developers are waiting to chop down. This is the culmination of a week-long protest by local people and supporters who have occupied the tree in an attempt to persuade the local council and the land owners not to fell it. The ‘irony’, the local paper reports, is that it is only a matter of time before the Emerald Ash Borer, which has already eaten billions of America’s trees, will probably destroy this one too. Yet surely that provides a stronger argument to protect the tree for the duration of its life. The protesters are asking only to be allowed to enjoy the tree for as long as it lives, but the council and landowners have decided that, if its life is limited, they may as well remove it at their convenience. During the week of protest, the owners change their argument from strategic planning to health and safety: they claim that the tree’s roots are raising a sidewalk, thereby presenting a potential hazard.

Financial gain is placed above human wellbeing. Clearly local people feel that the tree is an important focal point for their community. The furore surrounding its fate shows the intense connection that people feel for it and the stories that will be lost when the tree has gone. For a time it will be missed. Ash trees in Britain will be mourned, too, but let us hope that the John Innes Centre, and others like it, are successful in their endeavours to develop a variety of ash that is resistant to Dieback.

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