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. Eery 25 years, many of the trees in Bradfield Woods are cut down to the ground and then allowed to sprout and regrow. Credit: Jack Cripps 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. An old tree waiting to be cut again at Bradfield Woods. Courtesy of Suffolk Wildlife Trust 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. Weighed down by negative news? Our smart, bright, weekly newsletter is the uplift you’ve been looking for. [contact-form-7] 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.”