Restoring biodiversity in a rare ecosystem

Summer 2008

The 380 acres Bill Byers owns, which includes the farm his parents purchased in the late 1930s, is unique. Much of the land, located about 15 miles northwest of Hope, is adjacent to the largest blackland conservation site in the United States – the 4,885-acre Rick Evans Grandview Prairie Wildlife Management Area.

Originally about 12 million acres of blackland prairies and woodlands, which harbor more than 600 plant and 315 animal species, covered parts of Arkansas, Texas, Louisiana, Mississippi and Alabama. Because of their rich soils and often treeless landscape, blacklands were ideal for conversion to farmland and cattle pastures. Today Byers’ land is among some 10,000 acres of native blacklands that remain in scattered patches.

For the past three and a half years, Byers, who has lived in the area and raised cattle his entire life, has been working with The Nature Conservancy and the Arkansas Game and Fish Commission with grants from the U.S. Fish and Wildlife Service to restore much of his blackland property.

Prescribed fire is used as a restoration tool in the blacklands. (c) TNC

Two of the biggest problems that plague blackland sites are the absence of fire that keeps woody plants such as Eastern red cedars at bay and invasive plants that crowd out native vegetation.

“Without fire, cedars grow and can take over a blackland prairie,” says Seth Pearson, a land steward for the Conservancy. “When that happens, sunlight can’t reach the ground, which means native plants like wildflowers can’t grow.”

When cedars grow for several years, they become resistant to low-intensity fire that was historically a natural process in blackland ecosystems. Because of this, cutting cedars is often the first step in restoring blackland sites.

Since 1997 – the year the Arkansas Game and Fish Commission purchased Grandview Prairie – the agency has cut thousands of cedars at the wildlife management area and has followed the practice with prescribed fire. The results have been incredible. Cedar thickets have turned back into prairies teeming with hundreds of species of native plants, most noticeably vibrant wildflowers, that support a plethora of animal species. Monitoring before and after such restoration efforts has confirmed what the eye can easily detect – the blackland prairies are once again healthy and supporting rich biological diversity.

Vibrant wildflowers emerge after prescribed burns on blackland prairies. (c) Jay Harrod/TNC

For the past several years, the Conservancy and its partners have been working with landowners like Byers to replicate the success at Grandview Prairie on private property near the wildlife management area.

With funding from federal and state grants designed for private land management, Conservancy stewards have cut cedars on 550 acres of private property near Grandview Prairie in the last two years. They’ve also removed other invasive plants like tall fescue, Johnson grass and Chinese bush clover that can dominate the prairies, preventing native vegetation from growing.

Through the Landowner Incentive Program, which helps private landowners improve wildlife habitat on their property, the Conservancy has also restored fire to some 4,400 acres in the area since 2004, including Byers’ land and nearly 400 acres on a neighbor’s land this past October.

Before the cedars were burned, Pearson says they used limbs from the cut trees along with jute matting – a natural mesh-like product – to create erosion control barriers on Byers’ property. “The idea is that we’ll trap sediment long enough to allow native seeds to take root, which will stop the erosion in the long run,” he says.

Byers says the Conservancy’s stewardship activities on his land have definitely produced positive results.

“There’s no doubt it’s better,” he says. “It’s better for native plants – especially wildflowers. There’s more food for the wildlife now. There are some quail there, and I’m starting to see more. And the work is also helping the deer and turkey.”

The blacklands of southwestern Arkansas, a landscape dominated by tall native grasses, were covered by the Gulf of Mexico millions of years ago. As the Gulf receded, it left behind deposits of shellfish that formed a chalky layer underneath a deep mantle of rich, black soil. It’s from this dark soil that the blacklands get their name. Other blackland sites the Conservancy has had a hand in protecting include Columbus Prairie Preserve and Terre Noire Natural Area.