Lowland Raised Bog

Baston and Thurlby Fen Restoration Project - Lincs WTBaston and Thurlby Fen Restoration Project - Lincs WT

What is it?

Lowland raised bog occurs in shallow basins or on flat, low-lying areas where poor drainage waterlogs the ground and slows down plant decay. Over thousands of years, layers of sphagnum moss – pickled in the acidic water – have developed into huge peat domes, rising up to ten metres above the landscape. These raised peat bogs are 98% water (by weight) and occasionally form complexes where several domes can be found together, although each bog is distinct. 

Where is it found?

Intact lowland raised bog is one of Western Europe’s rarest and most threatened habitats. Around 94% of this unique habitat has been destroyed or damaged in the UK. The remaining 6,000 hectares (an area five times smaller than The Broads, our smallest national park) are internationally important as they are the last surviving remnants of a habitat rich in wildlife and history.

Why is it important?

Perched above, and isolated from, the local water table, lowland raised bog is fed entirely by rainwater, so is acidic and lacking in nutrients. Nevertheless, it supports a distinctive and unique range of wildlife. 

On undamaged bogs, up to a dozen species of sphagnum moss, ranging from brilliant green to ochre red, form a thin, living sponge layer over the accumulated peat. In turn, this supports other plants such as common cotton-grass, cranberry and bog rosemary. Sundews, butterworts and bladderworts supplement their lack of nutrients by trapping and digesting unwitting insects. 

Some of our rarest insects, including the large heath butterfly, mire pill beetle and several species of dragonfly thrive in the wet conditions of raised bogs. Mossy hummocks and pools also provide vital nesting and feeding grounds for wading birds, and birds of prey such as hen harriers and merlins which congregate on larger bogs to feed and roost during winter. 

Raised bogs have many other virtues as well as providing specialised wildlife habitat. They serve as important water systems, storing and filtering water for slow release. They are also of international value in terms of our heritage, providing a unique, living archive, stored in which is a record of climate, vegetation and landscape change since the last ice age over 10,000 years ago. 

Capable of recording even minor changes in nutrients, lowland raised bogs act as extremely sensitive indicators of the environment. In addition, they store carbon which is locked up in the peat; if they are drained, this carbon is released back into the atmosphere, adding to the greenhouse effect.

Is it threatened?

Afforestation, waste-tipping, opencast coal mining and road development have all taken their toll on lowland raised bog. But it is agricultural drainage and commercial peat extraction for horticulture, at wholly unsustainable rates, which are the most serious threats to this habitat.

Lowland raised bogs are protected under European law and our own national site designations. Despite this, plans to extract peat and drain surrounding areas still get consent.

How are The Wildlife Trusts helping?

The Wildlife Trusts are campaigning to raise awareness of the value of lowland raised bogs and the threats which they face, as well as promoting alternatives to using peat for gardening. 

We are working to prevent further loss of our lowland raised bogs by looking after many areas as nature reserves. We use traditional management techniques, such as grazing and burning, to maintain them, and we are restoring areas that have deteriorated. We also provide advice and guidance for landowners and farmers on wildlife-friendly practices in these areas.

What can I do to help?

  • Most importantly, buy peat-free products for your garden, make your own compost and don't buy plants grown in peat.
  • If you have raised bog habitat on your land take part in conservation measures to protect this habitat - ask your local Wildlife Trust for advice on management of raised bog.
  • Support the work of The Wildlife Trusts restoring and protecting bogs and their wildlife across the UK – become a member of your local Wildlife Trust.