Restoring the Wicklow hills: ‘It’s like the Sahara at times up there with peat moving around like sand dunes in the desert’

When I first came to live in Wicklow more than 40 years ago, I was fascinated by the mountains and I spent much of my spare time hillwalking. At that time, I thought that the mountains represented the most natural part of the east of Ireland. But something was missing. Birdsong was almost completely absent. There were sheep everywhere and very little woodland except for the uniform ranks of non-native conifers in state forestry plantations. Nevertheless, Ireland’s uplands form some of the largest expanses of semi-natural landscape, with almost 30 per cent of the country’s land mass estimated to be more than 150m high. However, erosion, drainage, uncontrolled burning, overstocking of sheep, growing numbers of deer and extensive afforestation have resulted in the widespread degradation of upland habitats, while climate change is already presenting a further threat. The results are loss of grazing potential, decline of typical upland vegetation and the loss of iconic birds such as the curlew and skylark.

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The effects of all the burning have left a legacy of bare and eroded peat in places. Not only is this bad for biodiversity but it also means that the exposed peat is emitting carbon to the atmosphere, adding to the already critical situation with the climate crisis. Faith Wilson is an ecologist who was engaged by an EU-funded project called SUAS (Sustainable Uplands Agri-environment Scheme) to survey and report on the condition of a number of commonages in the Wicklow Mountains. She says: “Some upland areas have been repeatedly burnt and the result is bare peat that is haemorrhaging carbon and on which there is no grazing for livestock. The peat is being washed off the mountains with ridges eroding and a high risk of landslides. Reduced capacity to absorb rain means a higher risk of floods downstream and increased flood intensity in lowland rivers. These are managed landscapes that need proper management. The legacy of upland burning in Wicklow and Dublin has been extremely damaging. The hills have been going wrong for a long time.”

Fortunately, there are a number of ongoing peatland restoration projects in the Wicklow Mountains National Park to address this. One of these sites is on Barnacullian Ridge, near Turlough Hill, where the peat is in the throes of total collapse. It is completely de-vegetated and the peat is just washing and blowing away, causing major issues downstream. Hugh McLindon, district conservation officer with the National Parks and Wildlife Service (NPWS), says: “It’s like the Sahara at times up there with peat moving around like sand dunes in the desert.” The physical impact of animals trampling and rubbing off the bare peat causes damage as well as preventing new growth taking hold. The mobility of the bare peat is phenomenal.

In order to arrest this, NPWS staff have fenced off areas to reduce the grazing pressure. They cut heather brash on neighbouring hills for spreading on the bare peat at Barnacullian. This has the added benefit of managing the vegetation at the donor sites while providing material for stabilising the bare peat on the restoration sites. The brash is excellent at creating a mat that prevents peat mobility and allows for mosses and grasses to establish. In places they spread lime, fertiliser and grass seed to create nurse or sacrificial grass and also to stabilise the bare peat. This grass then dies away as the liming is stopped and the acidity increases again towards a natural level in peat. After about three years, the native mosses and grasses are already establishing and will have almost completely colonised the site. By the fifth year, the site should be fully revegetated with native species.

It is the power of the water running off the site that does a lot of the erosive damage so the key to success is to slow this down. Hundreds of small dams are built across the gullies to trap the water. Retaining the water for longer within the bog allows sphagnum mosses to re-establish themselves. Without these mosses the bog has no chance of becoming “active” and capturing carbon again but in blanket bogs the gullying and steep slopes make it challenging to lift the water levels back to the surface uniformly. Effectively, it becomes a mosaic with different solutions being applied across the site. This labour-intensive work has been assisted by several voluntary groups, including Rewild Wicklow and Mountaineering Ireland, who can mobilise teams of Volunteers to help at weekends. McLindon says: “The team is constantly building a knowledge base on the local conditions and how different techniques work or not, but it is still early days. There are over 300 hectares of bare peat in the Wicklow Mountains National Park alone, so we’ll be at it for a while.”

Richard Nairn is an ecologist whose latest book Future Wild: Nature restoration in Ireland is published by New Island Books