AT THE heart of Scone Palace’s Victorian pinetum, where giant conifers soar to more than 40 metres, a Tsuga heterophylla (Western hemlock) is under the care of specialists. This tree, part of an avenue of hemlocks that marches through the pinetum, had been showing signs of fungal attack, so every two years it undergoes a Picus tomograph – the sonic equivalent of an x-ray – in order to determine the state of its health.

In its native Pacific North West, the Western hemlock can live for up to 1200 years, so the 130-year-old stripling at Scone is barely an adolescent, too young to be discarded if it can be saved.

“At one time trees such as this one would have been felled at the first signs of disease, but now we know that some can recover and that their seed may have genetic resistance,” says head gardener Brian Cunningham, who is responsible for one of the most famous designed landscapes in Scotland, where a sycamore (Acer pseudoplatanus) planted in 1617 by King James VI still flourishes despite having a limb torn from its trunk in the storm that swept through the estate a decade ago.

From Monday, until Tuesday, December 1, Scone Palace will be participating in the Scottish Tree Festival, the annual celebration of woodland heritage. Gardens, estates and nurseries across the country will be taking part, with real and virtual events, and organisers, Discover Scottish Gardens, hope that locals, ‘staycationers’ and those joining in from the comfort of their sofas, will experience the beauty of the season as it makes its progress through the leaf canopy of our largest plants.

At Attadale Gardens in Wester Ross, tours will take place every Thursday throughout the festival, giving visitors the chance to explore both mature woodland and new trees planted to replace those brought down by severe storms in the 1980s. Amongst the many highlights in this garden, set against the dramatic backdrop of Loch Carron, is a Wollemi pine, known only from the fossil record until 1994 when a grove of them was rediscovered in a steep-sided gorge in New South Wales.

At Cluny House Gardens, near Aberfeldy, the collection of trees from North America and the Himalayas includes a Torreya taxifolia or ‘Stinking cedar’, a relative of the yew, which has almost been wiped out in its native Florida, yet which, like so many trees from many diverse parts of the world, has found a save haven in Scotland.

At Cluny it grows amongst glowing acers and a Champion redwood, which is the widest tree of its kind in the UK. And at Gordon Castle near Fochabers there’s a chance to discover more about the 280 fruit trees that line the recently-restored walled garden.

Trees are so much part of the landscape that sometimes we fail to notice them until they put on their autumn clothes, but Catherine Erskine, chair of Discover Scottish Gardens, thinks that the events of this year have brought them into sharper focus.

“We are seeing a need for people to connect more closely with nature,” she says. “The idea of forest bathing, where you immerse yourself amongst trees, is increasingly being seen as way to improve wellbeing.”

At Cambo, her own estate near St Andrews, festival-goers will be able to walk slowly through woods, savouring the sights and smells of autumn, before enjoying wood-fired feasts beneath trees festooned with sparkling lights.

At Hopetoun House, on the outskirts of Edinburgh, rangers will take visitors into the past with tours that weave history and folklore and at Blair Castle there will be the chance to discover the legacy of the ‘Planting Dukes of Atholl’, who through the 18th and 19th centuries planted 27 million trees, transforming the southern approach to the Cairngorms in the process.

The planting mania of this era was fuelled by arrivals from the New World and it was Scots, such as David Douglas, who was born at Scone, and naval surgeon Archibald Menzies who were at the forefront of exploration and introduction.

The landscape that we see today owes much to their endeavours, from the Douglas Fir (Pseudotsuga menziesii), which clothes so many hillsides, to the Monkey Puzzle (Araucaria araucana), found on old estates and, incongruously, in small gardens whose owners fail to realise that they have welcomed in a Chilean giant.

Yet during the years when these new trees were arriving to dazzle us, Scotland’s own sylvan heritage was fading fast. At one time, the great Caledonian Forest covered 15,000 square kilometres but by the time conservation group Trees for Life was formed in 1993 only tiny fragments survived, scattered in remnants across the Highlands and on the brink of extinction as a result of felling, over-grazing and the loss of apex predators.

Trees for Life’s ambitious rewilding efforts may not have gone as far as reintroducing either wolf or lynx to curtail red deer, but the charity has worked closely with landowners to protect those remnants of the forest that remain and they have planted two million new trees in the process, harnessing the efforts of an army of volunteers who share their vision of seeing Scots pines once more dominate the landscape, giving shelter to the Western capercaillie and the Scottish crossbill, which breed nowhere else.

That the Caledonian Forest has not been consigned to folklore is in a large part due to their efforts but there is another Scottish forest that also needs rescuing. The Atlantic oak woods of the west coast are in fact temperate rainforest. Dripping with moisture, they are carpeted in moss and covered with lichens, some of which are found nowhere else in the world.

But there is a problem, this ancient woodland is not regenerating and unless the damage caused by deer and invasive Rhododendron ponticum can be reversed, then this magical environment could be lost.

According to the Woodland Trust this rare environment, which thrives only in oceanic climate zones, is one of the most diverse habitats for plants and wildlife in the UK, yet only 93,000 hectares remain. Plantlife Scotland’s ‘Secrets of the Celtic Rainforest’ project aims to raise awareness of the international importance of places such as Glen Nant in Argyll and Culag Woods in Assynt, while Forestry and Land Scotland has a programme of removing non-native species and replanting so that Slender Mouse-Tail moss, Greater Whipwort and other bryophytes and lichens will continue to flourish beneath a lush canopy of oak, hazel and birch.

On Skye, the John Muir Trust is planting 28,000 trees as part of project to restore native, broadleaf woodland on the Strathaird peninsula, but on the Sleat peninsula it is the imported conifer, Silver fir (Abies alba) growing in groves around Armadale Castle, that dominates the skyline.

These towering firs provide a shelter belt behind which many rare and exotic trees, many from the Southern Hemisphere, flourish, including a Giant redwood (Sequoiadendron giganteum) into whose soft and spongy bark, generations of children have sunk their fingers.

As part of the Scottish Tree Festival visitors will be able to follow trails through the trees, while children will be encouraged to clamber into branches and play on fallen trunks.

Christine Davis, of Armadale Castle, believes that it is these early encounters that sow the seeds for a lifetime’s love of nature and an awareness of the importance of trees in our lives.

“Amongst the trees here at Armadale are some of the originals that were planted in the 1820s, when the garden was established. They have witnessed so much history and survived so long that you can feel as if you have a connection with them.”

Christine’s favourite trees on the estate include the lime trees (Tilia x europaea) that once formed an impressive avenue, and the numerous acers that were part of a new wave of planting carried out in the 1970s.

“Their brilliant colours are just starting to emerge now and they are stunning.”

Higher in the canopy ash trees (Fraxinus excelsior) are also beginning to change colour and we should enjoy these while we can, because they are one of several species currently under threat. Ash dieback is a fungal disease that has swept across Europe and which may in time kill as many as 80% of all the ash trees in this country.

It comes hard on the heels of Phytophthora ramorum which has devastated larch trees (Larix decidua) and at a time when Dutch elm disease is still progressing northwards since its arrival in southern England in the late 1960s, supposedly arriving on timber imported from Canada to renovate the Royal dockyards on the Thames. It has taken its time to get here, but last year Aberdeen city was forced to fell hundreds of elms (Ulmus procera) that until now had remained untouched.

Yet it is not all bad news. There is hope that young trees bred from the few mature specimens that did not fall prey to the disease will see elms reclaiming their place in the landscape and the same may be true in the future for larch and ash.

It’s a message that’s not lost on a world that is awaiting its own miracle to see off the coronavirus. Perhaps if we learn to heal our woodlands and forests then we can heal ourselves too and emerge into a world where green shoots really do herald a recovery.

A full list of events is available from discoverscottishgardens.org/tree-festival

Tree Tales

The stature and longevity of trees has given them a special significance in the lives of those who live among them. Myths and legends have grown up around some, but sometimes the facts are even stranger than fiction.

Meiklour Beech Hedge

At 30m high and 530m in length, the Meiklour Beech Hedge near Blairgowrie is the longest hedge in Britain and the highest of its kind anywhere in the world. The trees that make up the hedge were planted in 1745 and legend has it that the men who planted it left to fight in the Jacobite Rebellion and never returned.

The Fortingall Yew

The Fortingall Yew, which grows in a village churchyard in Perthshire, is believed to be one of the oldest living things in Europe. Its age has been estimated at more than 3,000 years.

Cabbage palm trees

At 400 metres, the avenue of cabbage palm trees (Cordyline australis) that lines the drive to Logan Botanic Garden in Galloway is the longest of its kind in the UK.

Robert the Bruce's arrows

Botanist and landscape Maxine Ross has identified what she believes to be a longbow plantation on the Dalzell Estate in Lanarkshire. For the past four years, Maxine has been delving into the history of the yews (Taxus baccata) that grow along the Clyde Valley and she believes that the unusually straight yew trees growing within a ridge and furrow system on the estate were originally planted to be harvested for medieval warfare, perhaps by Thomas Dalzell who, in 1314, fought alongside Robert the Bruce at Bannockburn.

Giant redwoods

Benmore Botanic Garden in Argyll has launched an appeal to save its avenue of Giant redwoods. These giant trees are being weakened by root compaction and climate change and £80,000 is needed to carry out remedial works.

Slow growers

The Bristlecone Pine (Pinus longaeva) which grows in the mountains of California can live for more than 5,000 years, making it the longest-living tree on the planet. Bristlecone pines grow so slowly, surviving in cold winters, with very little water and in the teeth of such ferocious winds that in some years they do not make an annual growth ring.

Monkey Puzzles

In 1795, at a dinner given by the Governor of Chile, Archibald Menzies, botanist and surgeon who was born near Aberfeldy, stashed seeds from his dessert in his pocket. Once back on board his ship, The Discovery, he sowed them in frames and raised five seedlings These became the first Monkey Puzzle trees to reach Europe from the New World.

Chance find

The tall, thin columnar Dawyck beech (Fagus sylvatica ‘Dawyck’) was a chance seedling, found in 1860 by the owner of the Dawyck estate near Stobo in the Borders. Today Dawyck is a world-renowned arboretum and tree that carries its name still grows there.

Apple of our eyes

It was only with the collapse of the Soviet Union in 1991, when botanists from the West were finally able to visit Kazakhstan and Kyrgyzstan and share in the knowledge of local plant hunters who had been suppressed or died under Stalin, that the source of the domestic apple (Malus domestica) was revealed. Until then it was supposed the Romans had bred eating apples from sour crab apples (Malus sylvestris.)

Tea caddy tree

The glowing, mahogany-coloured bark of the Tibetan cherry (Prunus serrula) has made it a favourite tree for adding interest to the garden in winter, but in its native China sections of the trunk were traditionally polished to be made into tea caddies.