What is a heathland?
Heathlands are open areas of land at heights of 300m altitude or below with few trees and very poor sandy soil.
The main plant species that survive in these harsh conditions are heather, gorse and dwarf shrubs. The wetness of the soil will determine whether a dry heath, wet heath or bog is formed, all of which have their own unique plant and animal species.
Most of Dorset's heathlands are protected as Sites of Special Scientific Interest (SSSI) but some are also protected under European law as Special Areas of Conservation (SAC), Special Protection Areas (SPA) and Ramsar sites. They are also a priority habitat under the UK Biodiversity Action Plan (UK BAP).
Heathlands were formed as a result of the Bronze Age farmers clearing woodland to provide grazing and open areas to grow crops. The exposed poor soils were prone to leaching and became unable to support tree growth. Over the years, people used the turf for fuel and grazed their animals on the heath vegetation. These actions created the conditions necessary for the heathlands specialist wildlife to thrive and leading to the necessity of human intervention to maintain this important habitat.
What are the main threats to heathlands?
During the 1970s and 1980s the major threats to heathland were from industrial, road and housing developments or conversion to agricultural crops or forestry.
In 1989 a strategy was published to protect and enhance the heathland of Dorset, though development next to this important heathland is still a problem.
Grazing of heathland in years gone by has lead to the production of this unique habitat but changes in agricultural techniques has meant that the grazing of heath is no longer part of modern farming. Left ungrazed the heathland becomes invaded with scrub, causing heavy shading that will kill off the heathland vegetation.
See the Natural England leaflet Lowland Heathland - A Cultural and Endangered Landscape
How are heathlands managed so as to protect this unique habitat?
As heathlands were formed by the activities of man in the past it is necessary to actively manage them so as to maintain their wildlife value.
There are two main aims to heathland management, the first is to have a range of different aged heather and the second is to stop the colonisation of invasive plant species.
The main management plans involve light summer grazing by animals and some mowing of the heather to create mosaic patches of different ages and height. Grazing also helps in the control of the invasive species though it can also be necessary to use some herbicide spray.