Protecting coppice regrowth

Deer are the main threat to coppice regrowth. Where browsing is very severe, the coppice will fail to regrow, and the coupe may become dominated with rough grasses and sedges. Successful regrowth can also create a deer problem where none existed before, as young coppice is an attractive habitat for deer, and populations may rise in a woodland where coppicing is restarted.

When browsing, deer select leading shoots and upper leaves because they are actively growing, and therefore the most nutritious. Coppice regrowth is most vulnerable to attack in the spring and early summer after coppicing. By late summer the shoots should have grown above the browsing level. However protection for two seasons’ growth after coppicing is preferable.

Large populations of deer, and especially muntjac, also damage the woodland flora, including bluebells, wood anemones and other flowering plants, by grazing and trampling. The situation is complex however. Complete absence of browsing may lead to such dense and rapid coppice growth that the flowering plants, together with the butterflies that feed on them, are shaded out too quickly. Limited grazing by sustainable numbers of deer may give the best balance for coppice production and for biodiversity. See Savill, P S, Wright, H L, Miller, H G and Kerr, G (2001).

Techniques of control include:

• Fencing
• Disturbance
• Culling

Fencing

Full-height deer fencing with rabbit netting on the lower section is an expensive option, but forms a secure and durable fence. The Forestry Commission design for deer and rabbit fencing is shown here.

An alternative for species other than hazel, is to use treeshelters against rabbits and deer for the initial planting, and then to use temporary electric fencing or temporary plastic netting for two seasons after the first and each following coppice cut. In older coppices, which will produce a large amount of cut material, dead hedging can be constructed using the cut material.

The choice will depend on the type of protection required, and the availability of labour and other resources.

Temporary plastic netting

High tensile black plastic netting is available from several suppliers for temporary fencing against deer. The netting is proof against roe, fallow and sika deer, but not against muntjac deer or rabbits, which push and burrow underneath the fence. The netting is available in 1.5m and 1.8m heights, in 100m rolls. It is lightweight, with a 1.8m x 100m roll weighing 22kg. Temporary fencing can be removed after two growing seasons and re-used to protect another coupe. As noted above, this may improve the habitat for flowering plants and invertebrates by allowing grazing and browsing, provided that deer populations are not excessive.

The following specifications (Table 9e) are recommended by the Forestry Commission (Practice Note FCPN9, 1999).

Table 9e: Temporary fencing against deer

The netting should be attached with netting rings to two lines of 2mm high tensile wire, strained between straining posts. A suitable design of straining post is shown below. For the intermediate stakes, ideally use non-preserved locally-cut coppice poles, as the stakes are only required for two to three years.

It’s not recommended to attach the netting to standing trees, as without two strained line wires it’s not possible to get the fence sufficiently taut.

Measures to make the fence proof against muntjac will add considerably to the cost of the fence, as this will require adding hexagonal wire mesh (1050mm height, 31 mm mesh, 18 gauge) to the base of the fence, with the bottom 150mm lapped and pegged in the direction of attack. A third high tensile line wire is needed for attachment of the netting. This also makes the fence proof against rabbits, which may be useful in some situations.

Temporary electric fencing

Electric fencing can be moved from one coupe to another with the coppicing rotation. Systems using electric wire or tape are available from several manufacturers and suppliers of electric fencing, who should be contacted for further details.

Two examples are shown below. The three-line fence of high visibility electric tape is a deterrent to roe deer. The five-line wire fence is a deterrent to muntjac. The effectiveness of electric fencing will depend on deer population numbers, disturbance and other factors, and success is not guaranteed.

Dead Hedging

Dead hedging involves using some of the coppice material for making a barrier around the cut coupe. This technique has the advantage of using material from within the wood, much of which would otherwise have to be burnt. It is fairly labour intensive, so is very suitable for volunteer projects. Various different techniques are used, according to the labour and material available, and personal preference. The branching tops left after the coppice poles have been trimmed can be used, as well as unwanted scrub, brashings, rhododendron and other bushy material. Dead hedging is vulnerable to fire and vandalism, and the wider hedges may provide unwanted cover for rabbits.

• The simplest technique is to lay the material on the ground, with the butts towards the cut coppice, and the bushy tops outwards, towards the point of attack. A large amount of material is needed, as the barrier should be at least 1.8m (6’) high and will spread to at least 2.3m (8’) width. The barrier is quick to build, as it only involves carrying or dragging the material to the boundary and piling it up. The barrier must be continuous, and will need regular checking and repairing as necessary. A disadvantage is that, being wide, it provides perfect cover for rabbits.
• A second method, shown below, is to pile up the material lengthwise along the boundary, held in place by two rows of stakes, cut from the coppice. Knock the stakes in firmly using a post-driver, and then fill the area between with lop and top. Trample the lower layers to compact the material. Keep piling it up until the barrier is about 1.8m (6’) high. This type of dead hedge takes longer to erect than the method described above, but is more resistant to casual damage, and provides less cover for rabbits.
  
• A third method is to build a woven dead hedge, with the cut material woven through a single line of closely spaced stakes. This provides no cover for rabbits. Space the stakes about 1m (3’) apart, and pack the material closely so that it forms a hedge only about 300mm (1’) wide and 1.8m (6’) high. This uses a lot of stakes, but supply of stakes is not usually a problem when a coupe is cut.

All types of dead hedge can be made more difficult to penetrate by encouraging bramble to grow over it. This works especially well with the thin woven hedge. Dig up any newly rooted bramble shoots from the coppice, where they are unwanted weeds, and replant along the dead hedge. Young bramble plants are also easy to find in overgrown gardens, allotments and waste ground.

White or other easily visible tape stretched along the top of the dead hedge may also act as a deterrent by discouraging deer from jumping. Dead hedges are difficult to make proof against muntjac deer, which can get through by pushing and burrowing at the base. A tightly-packed dense base to the hedge will help deter them.

Disturbance

Make the newly-cut coupe as inhospitable to deer as possible.

• Cut as large coupes as possible within the planned rotation, and keep the shape of coupes fairly square, avoiding long or sinuous shapes which have a poor edge to area ratio.
• Clear the site of all cut growth so there are no places for the deer to lie up near the stools. Clear any adjacent rides.
• People working in the coupe for the following summer, making hurdles or other greenwood products, will discourage deer, as will any dogs which run around and mark the area. Alternatively, encourage public access where appropriate. During the spring and early summer, when the growth is most vulnerable to damage, it may be possible to arrange a rota of volunteers, preferably with dogs, to walk the coupe in the early morning and early evening.

Culling

As deer range over a wide area, culling is only effective if managed on an area basis. Culling is only permissible by licensed operators. Contact your local Forestry Commission office to see if there is a Deer Management Group in your area.