Coppicing Sweet Chestnut for Fencing Materials

Why Sweet Chestnut Rewards the Coppice Worker

Sweet chestnut (Castanea sativa) is the great survivor of the British coppice. Cut a stool to the ground in winter and by midsummer it will be wearing a crown of vigorous shoots, many of them a metre tall. Give those shoots fifteen years and you have straight, clean poles 10 to 15 centimetres across at the butt — the raw material for fence stakes, rails, gate hurdles, cleft pales and boardwalk decking.

In the Weald of Kent, Sussex and Surrey, chestnut has been cut on rotation for centuries, and some stools still worked today are thought to be several hundred years old. Few trees repay regular cutting so generously, and few give such durable timber without a drop of chemical treatment.

Getting the Rotation Right

Rotation length is decided by what you want to make. Chestnut grows quickly, so you can be flexible, but shortening the cycle gives you quantity at the expense of size and heartwood.

• 8 to 10 years — small spars, bean poles, hurdle rods and light pales.
• 12 to 16 years — the classic fencing rotation: stakes, rails, gate hurdles, cleft paling.
• 18 to 25 years — heavier posts, gate stiles, structural poles and thick boardwalk bearers.

The simplest way to plan a supply is to divide the wood into as many blocks as there are years in your rotation. Cutting on a fifteen-year cycle, fifteen roughly equal compartments give you one to cut each winter and a steady crop for ever. Mark the coupe boundaries and record the cutting year, because it is easy to lose track.

Cutting the Stools: Technique and Timing

Cut between leaf fall and bud burst — roughly late October to early March. Late winter is ideal: the sap is down, the wood is at its most durable, and the stool is ready to burst away as soon as the soil warms. Avoid cutting in the growing season, when you rob the stool of the reserves it needs for the next crop, and avoid working in hard frost, when poles can shatter.

Cut low and clean. A stump of 5 to 15 centimetres, taken off with a slightly angled face so rain runs off, will heal over and keep the stool alive for decades. High stumps are the commonest mistake in neglected coppice: they rot, split and eventually kill the very stool you are relying on. Use a sharp bow saw or chainsaw and leave a smooth surface, not a torn, crushed one.

Work carefully around each stool, taking the poles on the far side first so nothing springs back at you, and keep your feet clear of the butt as it drops. Keep machinery and vehicles off the stool itself; compacted soil around the base does lasting damage.

From Pole to Product: Sorting the Crop

Once the poles are down, sort them where they fall or drag them to a clearing and grade them. Good chestnut coppice gives several products from the same stool:

• Straight, thick poles — round fence posts, gate stiles, hanging posts.
• Medium straight poles — rails, braces, boardwalk bearers.
• Slender rods — hurdle weavers, pales, edging and pegs.
• Forked or bent pieces — the natural crooks that make the best gate braces and corner posts.
• Brash and tops — dead hedges, wildlife piles and firewood.

Chestnut splits beautifully. A froe and a mallet will rive a straight pole into clean, strong pales that hold far better than sawn timber — this is the traditional material behind chestnut paling fencing. If you want peeled poles, do it in spring, when rising sap lifts the bark. Stack everything off the ground with air moving through it, and season stakes for several months — ideally a year — before they go in the ground.

Durability Without Chemicals

Chestnut heartwood is packed with tannins, which makes it naturally resistant to fungal decay and insect attack. Round posts in ground contact regularly give twenty years or more, and cleft rails, pales and boardwalk decking will often outlast the wire and fixings around them. Weathering turns the surface a soft silver-grey without any loss of strength.

The practical rule is simple: heartwood lasts, sapwood does not. Short-rotation poles with a high proportion of pale sapwood are fine above ground, but for posts and anything bedded in soil, choose the older, darker, tighter-grained material from a longer rotation.

Keeping Stools Productive for Generations

The vulnerable period is the first two years after cutting, when tender new shoots are prime browsing for deer, rabbits and the occasional stray animal. Protect the coupe with temporary deer fencing, individual guards or a barrier of brash, and check it through the winter when food is short.

If you are growing big poles, thin the regrowth in the second or third winter, leaving the strongest six to ten shoots on each stool and removing the rest with a sharp hook or saw. Cutting in winter keeps the stool tidy and concentrates growth into the stems you actually want. Knock back bramble and competing scrub while the shoots establish, but leave some brash and standing deadwood for wildlife — a working coppice is one of the richest habitats in the British countryside.

Above all, keep cutting. Chestnut stools cut cleanly and regularly will produce for centuries; those left standing for forty years become overstood, with huge, brittle, rotten poles that are dangerous to fell and slow to regrow. A well-managed chestnut coppice is a crop, a fencing supply and a wildlife haven all at once — and it is renewed every time you sharpen the saw.