Prescribed Burns: Restoring the Wonder of Native Grasslands

Written by Will Thompson | Photos by Callie Broaddus

The flames crackled and glowed, burning slowly but intently through layers of dried yellowed grass and underbrush. Smoke billowed among the small crowd of onlookers appearing strangely alien — their faces obscured by fireproof suits and goggles — in the familiar landscape. The image was enough to conjure up feelings of panic: a bushfire crackling through a Hunt Country field. In reality, far from wreaking loss and devastation, this prescribed burn was started and maintained by the Warrenton environmental nonprofit The Clifton Institute as an essential step in caring for the health and vibrancy of a local native grassland.

Wild savannas and grasslands were abundant in the Piedmont of the eastern United States prior to widespread colonization and settlement. They were complex ecosystems that sustained bustling food webs of native grasses and flowers, insects and birds, and even grazing megafauna including bison. Today, the vast majority of these natural habitats have all but vanished as urban development, invasion by non-native pasture grasses, and the extirpation of bison and other species winnowed away the strands of these food webs. In place of the Piedmont’s once abundant native grasslands, our non-wooded areas are now almost entirely private lawns, gardens, and pasturelands. The occasional fox or snake sighting notwithstanding, most private fields and pastures are primarily fescue or lawn grasses that exclude native grasses and make a poor habitat for biodiversity.

Another reason that these native grasslands have receded from expansive ecosystems to a loosely bound mosaic of grassy patches is our modern practice of fire suppression.

“Fire is how grasslands were maintained historically,” explains Dr. Bert Harris, executive director of The Clifton Institute. “Fires were started naturally by lightning strikes or set by Indigenous Americans to corral game during hunting or to clear and manage land.”

Fast forward to today, and prescribed burns are being used as an effective tool in the efforts of landowners and conservation organizations to restore the Piedmont’s grasslands to their historical, and majestic, natural state.

“Native grasses have deep roots,” says Harris, explaining how native plants adapted to the natural fires that once routinely blazed through Piedmont savannas. “If you burn the native plants, it doesn’t hurt them. They’re playing the long game.” In contrast, most non-native and invasive grasses have more grass above ground, and shallower roots. As a prescribed burn rolls through a pasture of native and non-native grasses, it burns the invasive plants down to their shallow roots and clears aboveground fuel to give native grasses room to regenerate and spread.

As these native grasses begin to re-take root, the once degraded habitats spring back to life, in turn allowing declining plants and animals to recover and thrive.

“We found that these native grasslands are the most diverse plant communities in the entire state of Virginia,” says Harris. “That was really surprising. No one had ever studied native grasslands in the northern and central Piedmont of Virginia. We found nearly 500 species of plants, including several rare or threatened species.” In fact, just one of The Clifton Institute’s 50-by-2-meter grassland plots contained 93 species of plants, which made it the third most diverse vegetation plot in the state.

Plants are not the only species that benefits from restoring native grasslands. They are the foundation of healthy, biodiverse savanna ecosystems that are home to threatened species like the American kestrel, eastern meadowlarks, and bobolinks. Leaf-munching caterpillars and bugs, one of the cornerstones of a flourishing food web, haven’t adapted to the defensive chemicals in non-native plants, which also aren’t frequented by native pollinators. The result is non-native plants contributing to a comparably sterile landscape, devoid of the buzz and hum of insects and the songs of the birds who feed on them.

“The last remaining fragments of these native grasslands are slowly disappearing or are threatened by invasive plants or urban development,” says Harris. “More than 90% of Virginia’s grasslands are on private land, so there’s a big opportunity for landowners to play a key role in restoring these amazing ecosystems.”

The Clifton Institute is actively working with landowners to help them manage private lands in a way that benefits and restores natural ecosystems. Their programs include visiting properties, supplying seedling native plants, and hosting those interested on their 900-acre field station.

“Even if you have a smaller property, there are huge benefits to biodiversity by having native plants in your garden or you could have a small wildflower meadow.” Clifton also advises landowners on how to engage in prescribed burns, an effective first step in restoring a landscape suited for native plants and grasses, and welcomes volunteers during their burns.

“Most people who volunteer during a prescribed burn are surprised to be bored by it. We burn into the wind, very slowly,” says Harris. “Though, during our last burn, the flames did get to be 30 feet tall,” he added. “There’s always a little bit of excitement. I don’t recommend that people just start by lighting a match.” Harris does recommend that property owners interested in restoring native ecosystems reach out to The Clifton Institute, and in specific regard to prescribed burns, also get in touch with the Virginia Department of Forestry.

“There are numerous ways to get involved and there’s a lot that individuals can do,” Harris emphasizes. “We run educational programs and hold events for the public on our field station, and we are always looking for volunteers. In the bigger picture, the natural habitats and biodiversity of Virginia rely on people managing their fields and gardens.” The Clifton Institute is a 501(c)(3) nonprofit organization whose mission is to inspire a deeper understanding and appreciation of nature, to study the ecology of the Piedmont region, to restore habitat, and to conserve native biodiversity. Readers can learn more about The Clifton Institute, the opportunities to visit their field station for citizen science, and their volunteer programs and special events at cliftoninstitute.org. ML

Published in the April 2023 issue of Middleburg Life.