A GOV.UK case study presents Holnicote Estate as a practical example of how woodland management is being shaped by access law, species recovery and cost pressure. The National Trust estate covers 5,059 hectares in Exmoor National Park and includes a large area of access land under the Countryside and Rights of Way Act 2000, alongside 150 miles of public footpaths and bridleways.\n\nThat setting matters. The estate contains moorland, coast and woodland, including Horner Wood National Nature Reserve, a Site of Special Scientific Interest with 351.8 hectares of ancient oak woodland. Any intervention therefore has to work not only ecologically, but also legally and safely in an area used heavily by the public.
The government case study identifies grey squirrels as the main current threat to woodland habitat across Holnicote. Bark stripping affects both young and mature trees, particularly in the canopy, and the reported loss of 60 to 70 per cent of bark can leave trees weakened and more exposed to wind damage.\n\nControl options narrowed once pine martens were confirmed on the estate. The case study says lethal traps for grey squirrels were no longer permitted once pine martens were present, and it describes live trapping as operationally unrealistic at this scale. Effective live trapping would require lines of 40 to 50 traps, checked three or four times a day for around a month before a measurable effect was likely.
Holnicote's response has been to join a wider Exmoor grey squirrel control effort with neighbouring landowners and a syndicate of trained volunteers using low-powered air rifles. According to the GOV.UK case study, one trained volunteer removed around 150 grey squirrels from a heavily affected area between October 2024 and June 2025.\n\nThe operational detail is important because the woods are open to visitors. The case study says bait stations are fixed in locations chosen through risk assessment, with operators positioned away from public paths and steep valley sides used as backstops. In that set-up, a 16.27-joule air rifle was assessed as low risk. The same government account records ongoing monitoring of pine martens and Eurasian goshawks, both predators of grey squirrels, and notes plans within the wider Exmoor scheme for a further release of 10 pine martens.
On deer, the estate has deliberately moved away from the default assumption that fencing is the answer. The case study says fencing can protect young trees in the short term, but may simply displace browsing pressure into adjoining areas. It also creates a maintenance commitment and, in Holnicote's assessment, requires a clear plan for removal within 10 years.\n\nCost was a decisive factor at Riverlands Wood in Porlock Vale. Fencing the 17-hectare site against deer would, according to the case study, have cost roughly the same as employing a full-time wildlife manager for a year and covering initial equipment. The estate instead chose a more adaptive model, with government grants helping to fund targeted deer and squirrel control alongside overplanting of selected tree species. The stated aim is to reduce dependence on tree guards and fencing.
The distinction between red deer and roe deer is central to the estate's approach. The case study notes that red deer are an important part of the area's visitor economy, but identifies roe deer as the more immediate threat to young trees and coppice regeneration, especially in places where Eurasian beavers are present.\n\nAt Riverlands Wood, the estate is using Trico®, a deer repellent made from emulsified sheep fat, rather than relying on widespread guards or fencing. Each tree is sprayed twice yearly, in early spring and autumn, and the case study reports that browsing damage fell to below 20 per cent within the first year. It also adds an important caveat: the result may partly reflect deliberate overstocking of trees as well as the spray itself.
The monitoring plan is notably evidence-led. Holnicote intends to use Forest Research's 'nearest neighbour' technique on new planting to measure the percentage of browsing damage and test the relative effect of repellent treatment and tree density.\n\nAlongside this, the estate is maintaining glades and rides, in effect open patches and managed corridors along woodland edges, with highly palatable flora so deer have alternative browsing habitat. The case study says these features previously made up a relatively small share of the woodland, but are now designed into new plans with deer management as a main purpose. A secondary effect has been a reported increase in biodiversity value.
Lethal control remains part of the system, but it is described as selective and tied to a population objective of about 8 deer per square kilometre. That figure matters because it places culling within a broader management framework rather than treating it as a stand-alone answer.\n\nThe wider policy lesson from the GOV.UK case study is that woodland recovery on accessible and protected areas rarely turns on a single technique. At Holnicote, outcomes depend on combining habitat design, tree species choice, non-lethal deterrence and limited lethal control, while also accounting for public access duties, pine marten presence, workforce limits and grant funding. For other land managers, the transferable point is the need to set a clear tolerance for damage and then choose methods that are lawful, affordable and workable on the ground.