'Time capsule' area of buried prehistoric woodland discovered on Exmoor

An area of buried prehistoric woodland has been discovered on Exmoor.

The woodland and insect remains, dating between the Neolithic and Bronze Ages, were found preserved in the peatland “time capsule” taken from an area on the estate called Alderman’s Barrow Allotment.

The findings were unearthed during a year-long peatland restoration project at the National Trust’s Holnicote Estate in Somerset.

The work included constructing leaky log dams to help slow water flow through the valley and improve water quality.

This higher, more stable water table within the peat will also help reduce carbon emissions, increase the landscape's resilience to climate change, and preserve archaeology.

The discovery provides a snapshot of when and how the peat formed, as well as the kinds of species of plants and insects that lived in the landscape, many of which survive in similar wet woodland areas today.

Samples were taken at 5cm intervals to create a 1.5m deep sequence of peat, which was taken to a specialist lab at Wessex Archaeology in Salisbury to be analysed.

What was found?

Discoveries included over 100 fragments of Hydraena riparia beetles, a semi-aquatic beetle that flourishes in damp conditions and exists today, and prehistoric samples of dung beetles, rove beetles, moss mites, and water scavenger beetles.

Remains from a prehistoric woodland floor composed of fragments of trunks, small branches and twigs were found to date from around 4,500 to 3,500 years ago during the late Neolithic and middle Bronze Age.

These fragments revealed the presence of tree species including alder and willow, with evidence of birch growing nearby indicated by seeds.

After careful removal and analysis, woodland remains from other parts of the site, like a segment of willow tree, were found to date from as early as the beginning of the Neolithic age.

Plant remains recovered from the peat indicate that sedges and rushes were growing within the wet woodland habitat while birch and oak were present in the wider surrounding landscape.

Basil Stow, area ranger at the National Trust, said: “We’re really excited about these findings.

“It’s great to think that the discovery of the prehistoric insect and woodland remains provides an opportunity to understand the vegetation and the natural processes which helped establish this thriving wet, peaty, environment many thousands of years ago.

“Crucially, all of this information will help inform how we manage the landscape now and in the future.

“During this phase of restoration work we have created larger areas of wetland pools with woody dams.”

Dr Ed Treasure, from Wessex Archaeology, said: “These discoveries provide a unique and tangible way of connecting with Exmoor’s past, and they illustrate the changing nature of landscapes and reveal how this impressive landscape came to be.

“We can use this information to develop a ‘baseline’ for peatland restoration studies which can extend back centuries, if not millennia.

“This long-term view enables us to look beyond many of the significant changes in land-use practices in peatlands which occurred during the last few centuries.”

The peatland restoration work will also allow the peat to continue its role preserving valuable archaeology and paleoenvironmental remains to help build an understanding of the past environment and our interactions with it over thousands of years.

The work was carried out between the National Trust and the South West Peatland Partnership with funding from Natural England, South West Water, Duchy of Cornwall, National Trust and Cornwall Council.