Farming and conservation
The moorlands of Exmoor form an intrinsic part of the farmed landscape and its economy, providing grazing for sheep and cattle, wood fuel from its beech hedges and nectar for honey. The traditional farming practices which created and maintained moorland and heaths on Exmoor however are now under threat from the economic difficulties of modern upland agriculture.
In the past grazing with traditional breeds such as Exmoor Horn sheep and Devon red cattle in summer and Exmoor ponies through the winter was an important factor in maintaining the open areas. The introduction of hardier stock in the 19th century allowed for more intensive and winter grazing. Cattle cause trampling of delicate plants and poaching of the ground in wet winters, which favours rush invasion, and vehicles bringing supplementary feed cause erosion. More animal droppings cause an increase in soil fertility and all these factors combine to change the vegetation. Today many farmers no longer keep cattle which can graze moorlands as modern breeds are unable to survive on the course vegetation. Due to this and the unfavorable economics of upland agriculture many areas of heathland are now in danger of scrubbing over due to under-grazing.
Agriculture in the uplands would not be possible today without support from subsidy and since 1992 this has been in the form of Environmental Sensitive Area (ESA) payments for moorland farmers. A particular success of this scheme has been the continued maintenance of Exmoor’s many miles of beech hedges. Without the ESA payment of 80% capital works costs this would not have been possible. Recently the Higher Level Stewardship Scheme introduced by Natural England has continued to support farming in the uplands where clear environmental benefits can be gained. Nearly all of Exmoor’s moors and heaths are designated Sites of Special Scientific Interest on account of their special ecological value and this designation has ensured their continued protection. In the New Natural England HLS (higher level scheme) the focus is on ensuring SSSI areas are managed to keep their vegetation in good ecological and agricultural condition.
Moorland and Heath management by burning
Careful winter burning on heathlands, locally called 'swaling', is a traditional tool for the farmer. It keeps heather young, allowing more fresh shoots for stock to graze and reduces attack by pests such as heather beetle.
Traditionally burning of grass moorland also took place as a means of removing the cover of dead leaves which prevents light reaching the young grass shoots in spring, thereby allowing grazing earlier in the year. Frequent or intensive burning of grass moors however does not benefit wildlife. In order to achieve its farming aim, the burning of grass moorland needs to be undertaken every winter. Such intensive burning can only be survived by a few plants, generally grasses such as purple moor grasses (Molinia), which become unpalatable in late summer and actually decrease the grazing season as well as supporting little wildlife. Occasional light burning of moorland favours heather, but this may in turn take over to the detriment of other species, so that there is no good conservation reason for burning moorland except, perhaps, to divert grazing from more important areas.
Heathland is different. Unburnt heath supports a greater variety of wildlife than burnt, but will degenerate to scrub eventually. Light burning for farming keeps heather vigorous and provides good grazing, but may reduce the variety of wildlife. On the other hand heavy burning may also lead to lack of variety by allowing other plants to dominate. Too much grazing and burning encourages the spread of bracken which is unpalatable and harbours ticks which carry disease to stock. Research shows that creation of small patches with varying times between burns, some cutting and some unburnt patches seems to lead to greatest diversity of wildlife. This in turn improves grazing for farm animals and the natural control of pests. However, getting the balance right is difficult and much research needs to be undertaken in order to achieve the correct balance for each area of heathland.