It was once a verdant green canopy of mighty trees which stretched across Scotland almost as far as the eye could see.  

In ancient times the Caledonian Pine forest covered almost three quarters of the Scottish mainland yet has now dwindled to isolated pockets, threatened by climate change and depredation by man and deer. 

But now one isolated fragment of this dying biozone has been brought back from the brink after more than two decades of work to restore it to rude health.  

Experts have hailed efforts to replant and reserve Caledonian Pine forest on the Alladale estate in Sutherland as “wonderful” after they upgraded its status from ‘declining’ to ‘favourable’.  

Caledonian Pinewoods are a globally unique habitat can only be found in Scottish Highlands.  

It provides a home for a wide variety of rare and specialised species, including pine martens, conifer specialists like crossbills and red squirrels, as well as butterflies, lichens, fungi and wildflowers such as twinflower and creeping lady’s tresses.  

Only 84 fragments of the once-great forest remain, with a four-year study by the conservation charity Trees For Life finding that almost a quarter are critically threatened. 

The Herald: The area before restoration began...

The Caledonian pinewood at Alladale is the second most northerly fragment of and was designated as a Site of Special Scientific Interest by NatureScot (then Scottish Natural Heritage) in 1979.  

It is also recognised at a European level as a Special Area of Conservation in 2005.  

However, it was in decline until it was purchased in 2003 by the environmentalist Paul Lister who set about transforming the management of the estate and restoring natural habitats. 

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The Alladale team, with the support of NatureScot and the Scottish Rural Development Programme, fenced the pinewood fragment to relieve the deer grazing pressure and give an opportunity for pine seedlings to grow without the risk of being eaten.  

They also supplemented the forest area by planting almost a million new native trees. And now, an area that had two decades ago been only a few old pines is once again thriving and expanded massively.  

The Herald: ... and after 

In addition to Scots Pine, rowan, willow and juniper have also all increased in area and abundance. In time, these young trees will themselves set seed, ultimately ensuring new generations and a resilient Caledonian forest.  

This summer, NatureScot staff revisited the site to undertake an assessment of progress and found that the pinewood now meets all criteria to be officially classed as being in favourable condition. 

But first they had to get there, and found that traversing the now fertile ground is no longer a simple task.  

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Steve Wheatley of NatureScot, who undertook the most recent survey, said: “The survey was surprisingly hard work; in the absence of high deer pressure, the heather and blaeberry is now so high, just traversing the hill to undertake the survey was tiring but hugely rewarding work and it was a pleasure to spend time in such a special habitat and surrounded by nature. 

“We measure the condition of the important pinewoods against 15 different criteria which evaluate all the different layers of a native pinewood - from the canopy, to the health of the trees, to the shrub and ground layers, and all the way down to the soils. It was wonderful to see the Alladale Pinewood passing each one of these rigorous tests as the survey progressed.”  

The Herald: Paul Lister

Jeanette Hall, a NatureScot woodland specialist, added: “It’s wonderful to see the transformation of this ancient pinewood, particularly right now when nature restoration is so crucial part to tackle the biodiversity loss and climate change crises.”  

Reserve Manager at Alladale, Innes MacNeill, said, “A restored woodland and a healthy ecosystem is central to the vision for Alladale Wilderness Reserve. We have been working hard on this for two decades, so it is rewarding for us to reach this milestone and have this officially recognised.  

“The hard work will obviously continue; our ethos at Alladale is simple: we will leave the land in better condition than it was found.”  

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James Rainey, Senior Ecologist at Trees for Life, added: "With the climate and biodiversity crises intensifying, enabling the recovery of Scotland’s remnant pinewoods has never been more important. A globally unique habitat that people have valued for centuries, pinewoods also provide refuge for some of our rarest wildlife - from twinflower and wood ants to capercaillie.  

“Working collaboratively with land managers to protect ancient pinewoods is a fundamental first step to ensuring survival of these iconic woodlands.”