The Ancient Woodland Practice Boosting British Biodiversity

Every year, around the middle of summer, Alex Lack finds himself surprised by the buzz in Bradfield Woods, the forest he manages in Suffolk, a county in eastern England. Standing in a glade on a warm summer day, insects flit busily between shrubs and wildflowers. Hundreds of red admiral, peacock and brimstone butterflies float through the air. 

“There’s a constant hum of things flying around,” says Lack, who works with Suffolk Wildlife Trust. “It’s extraordinary.” 

Today, woodlands cover only 13 percent of the U.K.’s land area. But for centuries, much of Britain would have looked like Bradfield Woods — and hosted a similar melange of invertebrates, small mammals and plants of all sizes. “Half the countryside must have been like this at some point,” Lack says.

The U.K. is facing a precipitous decline in biodiversity, with one in six species at risk of disappearing. But Bradfield Woods is teeming with life, including endangered dormice, threatened nightingales, 370 flowering plant species and more than 400 types of fungi.

This forest is a refuge in part because every 25 years, many of the trees are cut down to the ground and then allowed to sprout and regrow, an ancient practice called coppicing. Bradford Woods has been managed this way for more than seven centuries — and now, the practice is being reinvigorated across Britain, from urban marshes to northern forests.

Coppicing, Lack says, is “probably still the best thing you can do for a broadleaf woodland of this type as a management tool from a biodiversity point of view.”

The process is simple: Hardwood, deciduous trees — such as oak, ash and birch — are cut back to the stump, leaving some of the larger trees to grow into maturity. New shoots emerge from the stool, as the stump is called. Then, after the sprouts grow into slim, straight poles — a period that could range from a couple years to 25 years — they get cut back to the stool. That leads the tree to regenerate new sprouts, and the process begins again.

Coppicing may have been practiced in England as early as the Neolithic period. A trackway built in the fourth millennium B.C. in England had a foundation of long wooden poles of the type that are harvested through coppicing. Written records from the Roman empire describe coppiced forests across Europe.

For thousands of years, coppicing supplied people across the continent with timber for building material and fuel, according to Keith Kirby, visiting researcher in the Department of Biology at Oxford University. Firm and springy ash wood became tool handles. Sheep were held in pens built from coppiced hazel. Oak coppice was an important supply for charcoal and an ingredient for tanning leather.

Through medieval times, most woodland across Britain was probably coppiced, according to Kirby — each tree species cut back at a different time interval based on its properties. And this cycle of coppicing had a big impact on the region’s plants and animals.

Each time the trees are cut back to the stump in a particular area, the forest floor is flooded with light. Low-growing vegetation, like grasses and wildflowers, spring up in the warm, bright clearing — attracting pollinators and insects. Brambles and shrubs take root, giving refuge to migratory birds. Eventually the shoots of the coppiced trees grow up and begin to cast the area into shade, until the trees are cut back again.

“You’ve got a patchwork of open woodland, dense thickets where it’s just regrowing, and then slightly older stuff,” Kirby says. “That’s really good for a whole range of species.”

Through the early 19th century, most of Britain’s woodland was probably regularly coppiced, according to Kirby. But after that, a range of social changes led to a decline. Technological advances made it easier to process larger pieces of timber, reducing the demand for the thinner wooden poles. Then, the tremendous loss of life during the World Wars of the 20th century meant that there were simply fewer young men working the British landscape.

Over time, Kirby says, some woods have been cleared for agriculture, or felled and replanted as single-species timber plantations. In some places, woodlands that were once coppiced were simply allowed to grow unchecked, becoming more mature forest. Fewer pockets of the landscape offered that dynamic mosaic of different vegetation where birds, insects and small animals had flourished.

“As that coppice went, so many of those species have gone into decline,” Kirby says.

Bradfield Woods is one of the exceptions. Historical records show that this land has been continuously coppiced since 1252, dating back to when it was owned by a Benedictine monastery. Some of the stools — tree root systems — are likely more than a thousand years old.

The forest is now managed by Suffolk Wildlife Trust with the goal of making it prime habitat for biodiversity, explains Lack. While coppicing for timber is often done in cycles as short as seven years, the Trust has adopted a 25-year cycle — rotating through the 70 forested hectares in order to create a range of habitats of different maturity.

“If you’ve got lots of ages across your woodland, you’ve got lots of different things living in each bit,” says Lack.

Bradfield Woods has a few factors that make it particularly prime for wildlife. The soil is very rich, and the long history of coppicing creates a more complex ecosystem. But as the state of biodiversity in Britain has come into focus, more places are employing coppicing as a tool to support animals and plants.

In a nature reserve on the site of a former gravel quarry in northern England, willows are routinely coppiced to support bird breeding habitat. A rewilding project at Hackney Marshes in London that involved coppicing and using the material for environmental restoration has seen an abundance of small mammals return to the urban wetland.

And elsewhere in Suffolk, about 30 miles from Bradfield Woods, woodland managers recently adopted a 10-year coppicing cycle in the forest around the archeological site of Sutton Hoo — believed to be the burial ground of a seventh-century king. After just one year, four pairs of nightingales were spotted in the habitat. The small songbirds’ population has declined by 90 percent across the U.K. since 1950.

Meanwhile, this approach to forest management is also growing as a business. Coppice workers around Leeds, in northern England, are restoring the cyclical cutting process to abandoned coppice woodlands, and turning the material into products. The workers’ cooperative Leeds Coppice Workers sells garden supplies like bean and pea poles, and installs garden fencing made from coppiced materials.

Tom Coxhead, a coppice worker and member of the co-op, says he sees coppicing benefiting the environment. Using material cut from local forests also helps connect community members with their woodlands.

“It works both economically and environmentally,” Coxhead says.

One of the biggest challenges is the U.K.’s growing deer population. The animals like to snack on young tree sprouts. Bradfield Woods is surrounded by a large hedge, which keeps the deer out. But fencing or similar deterrents can be an expensive option to try to protect coppice forests.

 The concept of cutting trees back to support nature may seem counterintuitive. Many woodlands that have a history of coppicing have been left untouched over the last century, growing into more mature forest. Some ecologists believe that allowing woods to grow without intervention is the best approach, according to Kirby.

Indeed, Kirby says mature forest does provide many benefits for wildlife when it is on a large scale, where clearings and varied habitats would occur naturally. But small patches of mature forest aren’t hospitable for low-growing plants and shrubberies, and the birds and insects that rely on those habitats. Coppicing, he says, helps make the most of the limited natural landscape in Britain.

“We’re trying to keep species in particular areas, because everything in between is farmland,” he says.

 For Kirby, there is another main benefit: the history.

 “We are in a cultural landscape,” he says. “Coppice has kept one bit of the natural forest ecosystem going successfully.”