Coppicing and Pollarding
Fancy a homegrown supply of beanpoles or a little bit of firewood? Coppicing is a traditional way to produce useful wooden poles, taking advantage of the ability of some trees to naturally regenerate from the cut base, or stool, with lots of long shoots.
Because coppicing prevents trees from maturing, it can also lengthen their lifespan. There is a lime tree at Westonbirt Arboretum in Gloucestershire that is thought to be 2,000 years old, thanks to coppicing.
Pollarding is a similar technique, but the cuts are made higher up the trunk, traditionally so that animals like deer and cattle couldn’t strip the fresh young growth. It’s also used on trees in towns to keep crowns in check in urban situations. Carried out repeatedly, it leads to swollen areas on the tree trunk from which new shoots grow. The resulting lumpy trunks were once described as “warty railway sleepers with a shock head of twigs” by a Victorian journalist, but the brightly coloured stems of willow seen along river banks have great aesthetic appeal.
There is evidence of coppicing going back thousands of years. Wooden walkways dating from the Bronze Age, such as the Sweet Track in Somerset, have been found to contain coppiced wood. Cutting the underwood (another name for coppice poles) was also described as a common practice by John Evelyn in his 1662 tract on forestry, Sylva. Pollarding was more likely to be found in wooded pasture, rather than in forests, or marking boundary lines.
Coppiced and pollarded wood was traditionally used for fuel, basketry materials, fencing, hurdles, building materials, broom and tool handles. Ash was particularly used for handles while sweet chestnut makes for good fencing material and flexible willow for excellent baskets. Faggots (bunches of branches) were also stored as winter fodder for livestock, also known as tree hay.
Coppicing fell into disuse in the mid-20th century as fossil fuels took over and plastic, light metals and other materials became prevalent in manufacturing. It is also labour intensive, so expensive to carry out. Abandoned coppice woodlands can be recognised by the multiple thick stems growing from stools, sometimes fused together. The practice has enjoyed a revival in recent decades as a conservation practice, however, due to the biodiversity benefits of opening up the woodland floor. The added light allows other plants to flourish, which brings in the likes of butterflies and dormice. The poles now make for lovely rustic plant supports and an alternative to bamboo canes.
How to coppice
Coppiced woods are usually divided into units, or coupes, which are cut on a cycle. This means that the wood in each coupe is at a different stage of regeneration. For example, on an 8-year cycle, you could divide the wood into 8 coupes and carry out coppicing every winter.
As a traditional countryside activity, professional coppicing is a little practised craft, however there are some workers keeping the technique alive. There are various regional groups who may be able to help if you are looking for a coppice worker.
Coppicing involves cutting a tree down to within 15cm (6 inches) of the ground. This is carried out in winter, while the tree is dormant. Cutting at this time of year means there is no foliage to get in the way, the poles are free of leaves and the tree will not bleed any sap. It also avoids the nesting season (it is illegal to disturb nesting birds in the UK). Cuts can be made with pruning saws or chainsaws and should leave a clean stump with no tears in the bark.
Types of tree that can be coppiced include hazel (Corylus avellana), sweet chestnut (Castanea sativa), lime (Tilia species), oak (Quercus), sycamore (Acer pseudoplatanus) and willow (Salix species). To establish a new coppice, plant bare root whips at 1.5 to 2.5m spacings. These need to be cut down after about 5 years to encourage the stool to develop. It may seem drastic, but the tree will spring back to life in spring and the regrowth can be surprisingly rapid. It is not unknown for willow to grow 4m in a season!
The period the poles are left to grow between cutting then depends on the species and products required. Material is usually allowed to grow for 7-15 years, with larger timber resulting from longer growing periods.
How to pollard
Pollarding involves cutting the tree at 2-5m from ground. As with coppicing, this is ideally carried out from when the tree is young, and done in winter. Pollarding is carried out from every 1-2 years. Branches are pruned to just above the previous cut, where a swollen knob develops that contains plenty of dormant buds.
The most common reason for pollarding these days is to control tree size, so it is usually carried out annually once the tree is at the desired size. Heavy branches growing from a pollard can be dangerous. Lower level cuts can be carried out from ground level, while higher cuts call for a qualified professional to climb up with ropes.
Trees that respond well to pollarding include ash (Fraxinus), common lime (Tilia x europaea), elder (Sambucus), London plane (Platanus acerifolia), Oak (Quercus) and tulip tree (Liriodendron tulipifera).
It is not possible to pollard a tree that is already mature. Cutting through mature branches is called topping and these cuts heal badly, leaving the branch open to pathogens and dieback. It can also look unsightly.
Coppicing and pollarding in the garden
Coppicing and pollarding can have an ornamental purpose in the garden. For example, dogwood and willow are coppiced in March to encourage bright stems. It is also possible to treat foxglove tree (Paulownia tomentosa), Indian bean tree (Catalpa bignoniodes) and Judas tree (Cercis siliquastrum) as multi-stemmed shrubs by cutting them back each year. This produces super-sized leaves that look great at the back of a border. Again, carry out in late winter-early spring and the plant will quickly grow back to try and re-establish itself.
Do wait a year or two after planting before hard pruning like this. Cutting back to 60-100cm from the ground will give you a pollarded shrub and to 5-8cm will give you a coppiced shrub. (Make sure you don’t cut below a graft, though!) Make clean cuts with secateurs, loppers or a pruning saw, depending on the thickness of the stems. Fertiliser or organic matter, applied in spring, will help things along.
Older broadleaf trees can be felled to create a coppice stool, but it is not always successful. Anyone who has tried to get rid of a sycamore will know that it is almost impossible to kill by cutting down to ground level, but your prized saucer magnolia might be another matter!