Heathland and moorland
The story of heathland
This story is particularly intriguing because it explains how one of our most wild-seeming landscapes is in fact almost entirely a product of the long-standing interaction between humans and nature. The development of heathlands began at least 5000 years ago, when humans started clearing trees growing on infertile soils, probably to entice game into clearings to make hunting easier, and later to graze domestic livestock. In some areas repeated layers of charcoal show that the forest was cleared repeatedly by fire for grazing or temporary crops.
Most heathlands are thought to date from the Bronze Age some 3000 years ago, although some are more recent, for example, where forests were felled by charcoal burners to supply iron forges, as in the Sussex Weald. The removal of trees and livestock grazing caused the nutrient levels to fall further and the soil acidity to increase – conditions that particularly suit heathland plants. Before forest clearance became wide-scale, these plants were limited to coasts, cliff tops and mountainsides, where exposure prevented taller woody plants from flourishing, and to temporary forest clearings after wind, drought or fire had reduced the tree cover over thinner soils. With the removal of the forest canopy by humans they were able to expand wherever the soils were suitable.
If undisturbed, heathland naturally develops back into woodland as tree species become established and gradually enrich the soil. However, heathlands became integrated into the farming system, providing livestock grazing, heather for thatch, turves for fuel, bracken for bedding and potash, gorse for bread ovens and livestock fodder and sands and gravels for building. Constant disturbance prevented the natural succession and maintained a landscape that we now value for cultural reasons as well as its unique wildlife.
Types of heathland
Heathland is found from sea level to about 1000m. The low soil fertility means that heathland is generally characterised by a small number of plant species, of which various heathers are usually dominant. Despite this, there are significant differences in heathland depending on climate, altitude, terrain and wetness, and the nature of the underlying substrate.
Upland heath is found over shallow peat and mineral soils in the north and west of the UK and in the southern uplands (e.g. Dartmoor and Exmoor). Here we refer to this as moorland, (this term is also often used to include other upland habitat such as blanket bog). Lowland heath is found below about 300m on more freely draining sands and gravels. Both habitats can include wet and dry vegetation communities. Some types of dry heath are dominated by low-growing lichens and grasses (such as in the Brecklands and Suffolk Sandlings), and heathland can also be found in old stabilised acid sand dunes or, more rarely, on shingle beaches.
Occasionally heath develops on limestone where a thin layer of windblown sand allows heather to flourish next to lime-loving plants such as dropwort and salad burnet. These are “semi-natural” habitats, requiring human intervention to persist in the long term - the only truly natural types of heathland are montane and maritime heath. Montane heath is found at high altitudes (above about 700m), where exposure prevents the development of taller shrubs or trees and maritime heath is found on cliff tops, particularly on the Atlantic coast, where strong, salty sea winds keep the vegetation clipped short.
The demise of heathland and hope for the future
In the lowlands, the decline in the value of heathland to the local rural economy resulted in the link between heathland and more fertile farmland being lost leading to fragmentation, abandonment and conversion to other uses. Around 85% of heathland has been lost over the past 150 years (particularly during the second part of the 20th century) through agricultural ‘improvement’, afforestation with conifers and development. The relatively small parcels of fragmented habitat left fell out of use and natural succession (often aided by wind-blown seed from nearby plantations) led to the development of secondary woodland, with the loss of many specialist heathland species. Since then, conservation programmes have sought to reverse the decline of heathlands through appropriate management and restoration. Today heathlands are no longer seen simply as wasteland and are valued for their wildlife and cultural history. They are also appreciated as open space for recreation – although this can bring its own challenges, particularly where development has brought towns and villages closer to heathland.
In the uplands, the story was different. Moorlands retained close links with agriculture, but the change from mixed farming to sheep-rearing from the mid-18th century onwards initiated the over-management of upland heathland that we are still struggling with today. In the Highlands, the communities that had played a fundamental role in maintaining the cultural landscape were brutally restructured as landlords sought to maximise gain from sheep farming. Priorities again shifted with the rise of shooting estates in the 19th century and an increase in burning and grazing drove the large-scale conversion of heathland to impoverished grassland, a problem exacerbated in the late 20th century by the way agricultural subsidies were allotted. Also in the 20th century, forestry and financial incentives led to the loss of huge areas of moorland and blanket bog to forestry.
In recent decades, conservation efforts have done much to reverse the fortunes of heathland. Direct loss through development, “improvement” and afforestation have been halted. Restoration projects have increased the area of heathland and arrested succession to secondary woodland. Livestock grazing is once again a common sight on larger heathlands, and focussed management seeks to replicate past use and bring many heathland rarities back from the brink of extinction. However, the challenge of how to secure a sustainable future for heathland through reintegration into local communities remains.
How you can help
Across the UK The Wildlife Trusts are working to restore this balance and protect our heaths by clearing encroaching scrub, reinstating grazing regimes and reseeding heathers. We are also campaigning for protection from development and encouraging local people not to disturb ground-nesting birds. This work is vital if our rare heathland wildlife is to survive.
The Wildlife Trusts manage many heathland habitats for the benefit of wildlife; by volunteering for your local Trust you can help too, and you'll make new friends and learn new skills along the way.