Scotland is often pictured as a land of open, treeless glens, a landscape that seems naturally bare and windswept. However, this perception obscures a complex history of environmental change. The country’s current forest cover stands at only around 18.5% of its total land area, significantly lower than the European Union average of 38% to 43%. Historically, this figure was even lower, dropping to 5% in 1919. The scarcity of trees today is due to a combination of natural environmental limitations and centuries of intense human activity that reshaped the terrain. Understanding this requires looking back at the original forest extent and the historical, economic, and ecological forces that led to its decline.
The Original Forest Cover
Following the last Ice Age, Scotland’s landscape was far more forested than it is now. This ancient woodland, known as the Caledonian Forest, was a temperate rainforest ecosystem dominated by native Scots pine, birch, oak, and rowan. At its maximum extent, this wilderness is estimated to have covered up to 1.5 million hectares of the country.
Even before significant human impact, natural factors limited the forest’s reach. A shift toward a cooler, wetter, and windier climate around 2000 BC naturally reduced the tree line, especially at higher elevations. The widespread formation of peatlands, where waterlogged conditions prevent organic matter from fully decaying, also created large areas unsuitable for tree growth. Despite these natural constraints, extensive woodlands persisted across the landscape.
Historical Drivers of Deforestation
The removal of Scotland’s forests began gradually with the earliest human settlements. Neolithic farmers cleared small sections of woodland to create grazing land for livestock. This clearance intensified during the Iron Age, driven by the needs of an expanding agrarian society.
The decline accelerated from the 16th century onward due to industrial and military demands. Timber was harvested in large quantities for shipbuilding, particularly during periods of conflict, and for use in the charcoal-fueled iron smelting industry. This extraction was often poorly managed, leading to the rapid depletion of old-growth stands without any provision for regeneration.
The Highland Clearances in the 18th and 19th centuries delivered a major blow to the remaining woodlands. Landowners forcibly evicted tenant farmers to make way for large-scale sheep runs. The density of sheep across these tracts of land halted natural forest recovery, as the animals grazed young tree saplings before they could establish themselves. This shift in land use turned huge areas of the Highlands into open landscapes managed for livestock and deer stalking.
Ecological Factors Preventing Regrowth
Even with the end of large-scale felling, the forests have not been able to recover naturally due to ongoing ecological pressures. The largest impediment to natural regeneration today is the high population density of grazing animals, primarily red deer and sheep. These herbivores browse on the shoots and saplings of trees, creating a “browse line” that prevents young trees from growing tall.
In many parts of the Scottish uplands, red deer densities exceed five individuals per square kilometer, a level considered too high to permit successful woodland regeneration without fencing. Since the natural predators of large herbivores, such as wolves and lynx, were long ago exterminated, culling and winter mortality are the only factors controlling deer numbers. This intense grazing pressure maintains the landscape as open moorland.
Soil degradation resulting from centuries of deforestation and overgrazing also presents a significant challenge. The loss of tree cover led to the formation of thin, acidic, and nutrient-poor soils, with vast areas covered by peat. These conditions are less hospitable to tree establishment, and the high winds and heavy rainfall common at altitude further stress any newly planted trees.
Current Reafforestation Initiatives
The trend of deforestation has been reversed in the last century, with Scotland’s forest cover increasing from 5% to its current level of approximately 18.5%. The Scottish government has set a target to reach 21% forest cover by 2032, which requires an increase in planting rates to 15,000 hectares per year. This expansion effort is divided between commercial forestry and ecological restoration.
A proportion of the new planting uses commercial conifer species, such as the non-native Sitka spruce, primarily for timber production. There is also a growing focus on restoring native woodlands, with a target to create 3,000 to 5,000 hectares of new native forest annually. These native woodland projects aim to restore the Caledonian Forest ecosystem using species like Scots pine, oak, and birch, often requiring extensive fencing to exclude deer and sheep.