Fertile Legacy

When it comes to vanishing prairies, even the smallest remnants are worth saving

Brianna Randall
Conservation
Oct 04, 2022

Amid a cornucopia of native grasses and wildflowers, a monarch butterfly caterpillar feeds on swamp milkweed during summer on a prairie in Missouri. Some prairies shelter more plant species per square foot than tropical rain forests. (Photo by Noppadol Paothong)

ONE HUNDRED MILES NORTHWEST OF CHICAGO, a patch of prairie no bigger than a couple of city blocks teems with life. Never paved over or plowed under like the majority of North American grasslands, Bell Bowl Prairie is home to 146 plant species that draw in rare birds—including Bell’s vireo, blue grosbeak, black-billed cuckoo and upland sandpiper—as well as at least 100 bee species. Thanks to the efforts of conservationists, one of those bees—the endangered rusty patched bumble bee—may help save this 10,000-year-old treasure trove of diversity, which is now slated to be bulldozed for a road to expand Chicago Rockford International Airport.

In August 2021, when neighbors first noticed excavators poised alongside the prairie, 6.2 of Bell Bowl’s original 21.7 acres already had been destroyed. Alarmed, these residents notified the Illinois Department of Natural Resources and the nonprofit Natural Land Institute (NLI), which for the past 50 years has coordinated with airport officials to steward the land. A few days later, a staff member from each organization went out to investigate—and found the rare bumble bee nestled amidst Bell Bowl’s lush grasses and wildflowers.

Decimated by habitat loss, pesticides, disease and other threats, the rusty patched has vanished from an estimated 90 percent of its historic range. In 2017, it was federally listed as an endangered species, the first bumble bee ever to receive such protection. Because the bee has an especially long foraging season—requiring diverse plants with flowers that bloom from April through September—remnant prairies such as Bell Bowl are critical in locations where it has survived. Beginning in October, the small prairie also provides ideal habitat for queen bumble bees and their eggs to overwinter a few inches beneath the surface of the soil, where they will emerge the following spring.

The bumble bee’s discovery provided ammunition for conservationists to fight the prairie’s destruction. In September 2021, NLI, the nonprofit Friends of Illinois Nature Preserves (FINP) and other local groups and individuals launched a campaign to oppose the road project. “This type of high-quality prairie is extremely rare,” says NLI Executive Director Kerry Leigh. “Because they’re Illinois’ iconic landscape, we consider ancient remnants on par with the redwoods.”

Leigh says the institute has offered to help airport officials find funding to cover costs of redesigning the project in a way that preserves the prairie. The group also is exploring strategies in which keeping Bell Bowl intact would benefit the airport. Leigh notes, for example, that airports often look for ways to offset carbon emissions, which could include maintaining the carbon stored underground in the prairie’s dense root systems. “The old conservation protection paradigm was ‘either-or,’ but we feel we can have both,” she says. “It’s really important to Rockford’s economic development that we have this airport expansion. And it’s really important that we preserve this unique ecosystem with its incredible web of life.”

Last October, national organizations joined the effort to save Bell Bowl, including the National Wildlife Federation, which sent its Illinois members an “action alert” asking them to urge airport officials and state decision-makers to reroute the road around the prairie. “Conserving ancient remnants such as Bell Bowl is critical because these are irreplaceable habitats,” says Julie Sibbing, NWF’s associate vice president for land stewardship. “Protecting what’s left gives us the best chance of restoring grasslands to ensure survival of declining species such as the rusty patched bumble bee.”

Together, these conservationists’ efforts met with success—at least temporarily. On October 28, 2021, the airport put its construction project on hold while the U.S. Fish and Wildlife Service reviews a new environmental assessment and the Illinois District Court considers a lawsuit filed by NLI. As of early August 2022, however, when this issue went to press, airport authorities still planned to bulldoze Bell Bowl in mid-October unless ordered not to by a court or federal agency.

A patch of Bell Bowl Prairie near Chicago Rockford International Airport

Located precariously close to Chicago Rockford International Airport, Bell Bowl Prairie (above) is slated to be destroyed as part of an airport expansion project. In barely 20 acres, the habitat is home to 146 plant species (including native wild plum, foreground) that feed and shelter rare birds such as Bell’s vireo (singing at Bell Bowl, below).

“Biological metropolis”

Activists fighting to save the remnant prairie say Bell Bowl’s loss would be a tragedy. “Stepping into an old-growth prairie is magical, like entering a biological metropolis,” says Robb Telfer, FINP’s Save Bell Bowl Prairie campaign manager. “Each one is unlike anywhere else in the universe,” he adds. “I would love for society to look at our remnants and say these are the most sacred nature we have.”

A Bell's vireo perches on a branch and sings

Scientists who study North American grasslands agree that prairie remnants such as Bell Bowl—ancient habitats, equivalent to old-growth forests, that have never been razed—are far too important to lose. Once covering a third of the continental United States, grasslands have disappeared from half of their original range, most of them plowed under to make way for row crops such as corn and soybeans.

“Of all terrestrial ecosystems, temperate grasslands are one of the least protected and most threatened,” says Carol Davit, executive director of the nonprofit Missouri Prairie Foundation, whose state has less than one-half of 1 percent of its original prairie left. These prairie ecosystems nurture an amazing amount of biodiversity, with some boasting more plant species per square foot than tropical rain forests. Below ground, the plants’ dense root systems cycle nutrients, hold water, store carbon and create some of the world’s most fertile soils.

Davit says Bell Bowl’s diminutive size makes it no less valuable. Often, “habitat size has been stressed without looking at the biodiversity of that habitat,” she says. “But some of our smallest remnant prairies are teeming with life,” she adds. “They should never be written off.”

Davit cites a study, published in 2018 in the Proceedings of the National Academy of Sciences, underscoring that point. After analyzing 31 case studies in 27 countries across four continents, the authors concluded that “small, isolated patches are inordinately important for biodiversity conservation,” they write. That same year, a remnant prairie owned and managed by Davit’s organization, called Penn-Sylvania Prairie, set a new world record for plant richness when botanists recorded an astonishing 46 native plant species in a single 20-by-20-inch plot.

A rusty patched bumblebee on a yellow flower

Seeking food during their spring migration, bobolinks stop at Bell Bowl Prairie (below), which also nurtures at least 100 bee species—including the endangered rusty patched bumble bee (above). In Tennessee, May Prairie (bottom) houses 300 plant species in just 12 acres of grassland. These plants include at least one, Estes’ aster, found nowhere else in the world.

Saving species—and seed sources

Beyond biodiversity conservation, small prairie fragments provide other benefits, says Davit. In recent years, for example, conservationists increasingly have emphasized the value of creating wildlife corridors and habitat connectivity. “But you can’t have those unless you have some habitat to connect to,” she says.

Remnant prairies also are essential seed sources for the plants needed by native plant nurseries and land managers working to restore grasslands that have been destroyed. In addition, surviving remnants provide templates for re-creating those lost habitats. And like Bell Bowl, they often are located in or near cities, providing residents with opportunities to experience rare native ecosystems and the diversity of life they support. “Not everyone can afford to travel long distances to visit a national park,” says Davit. “But many people can walk, drive or ride a bike across town”—where virgin prairie may run alongside old railroad tracks, for example.

Or even busy highways. In Iowa, where just 1/1000th of the state’s original ancient prairie remains intact, many surviving remnants grow in 30-foot-wide strips along roadsides. To protect these remnant prairies, Iowa was one of the first states to establish Integrated Roadside Vegetation Management to foster healthy, native plants along county, state and federal roads and highways. Since 1988, roadside managers also have restored more than 50,000 acres of prairie in places that had been mowed, sprayed with herbicides or otherwise damaged. The native grasses and wildflowers they planted came from seed collected in the state’s remnant prairies.

“These remnants are what’s left of nature in one of the most radically altered landscapes on the planet,” says Laura Jackson, director of the Tallgrass Prairie Center at the University of Northern Iowa. “When you walk into one, even if it’s tiny, all of a sudden you’re in a wild place.”

In the southeastern United States, prairies that escaped the plow or paver frequently have been shrouded by forests instead. Historically, trees were kept in check on these grasslands by frequent blazes set by lightning or Indigenous Peoples. Regular grazing by bison, elk and deer also helped keep these habitats open. When European settlers suppressed fires and eliminated bison, however, trees proliferated, outcompeting grassland plants for sun, water and nutrients.

Pennsylvania leatherwing beetles feeding on Leavenworth’s eryngo

Male greater prairie-chickens (below) vie for mates on the Flint Hills of eastern Kansas, a prairie that supports myriad other species, including these Pennsylvania leatherwing beetles feeding on Leavenworth’s eryngo (above). Says one activist: “I would love for society to look at our remnants and say these are the most sacred nature we have.”

Prairie plant superpowers

But scientists have discovered that prairie plants have superpowers: They can come back to life after lying dormant for decades. As long as their root systems and seed banks are still intact, native grasses and wildflowers spring up again once sunlight reaches the ground.

On wildlife management areas in Tennessee and North Carolina, land managers have restored grasslands by thinning the forest and using prescribed fires to reinvigorate soil. Researchers monitoring three areas from 2008 to 2016 found more than 350 herbaceous species growing after restoration projects compared to about 118 species growing before. In Tennessee, one restored grassland on the Catoosa Wildlife Management Area today shelters uncommon birds such as the prairie warbler and northern bobwhite along with rare insects such as the frosted elfin butterfly and declining mammals such as the golden mouse.

Two male greater prairie-chickens vie for mates

“While many places in the Southeast may look like a forest today, we would argue that they’re actually remnant savannas suppressed under leaf litter and heavy shade,” says Dwayne Estes, co-founder and executive director of the Southeastern Grasslands Initiative (SGI) at Austin Peay State University. He and colleagues at SGI hope to restore more southern grasslands while continuing to protect and expand surviving remnants. “Grasslands are on their last leg across the Southeast,” Estes says. “What type of impact has that had on wildlife? It’s probably one of the reasons we’re seeing the collapse of species like the northern bobwhite.”

Estes points to a 12-acre grassland within May Prairie State Natural Area in Manchester, Tennessee, as a success story of how and why to save small remnants. The state purchased the tract from a real estate developer and banker—who named the prairie after his wife, May—then designated it the first Tennessee State Natural Area in 1973. The prairie is also recognized by the U.S. Department of the Interior as a National Natural Landmark. One of the state’s most floristically diverse places, May Prairie boasts a phenomenal 300 plant species in its small open grassland area. Twenty-five of these plants are considered rare in Tennessee, and at least one of them—Estes’ aster, named for Dwayne after he discovered it here in 2008—occurs nowhere else in the world.

May Prairie “is truly a sacred gem when it comes to landmarks within the eastern United States, a virgin old-growth grassland,” says Estes. “We’re trying to save more remnants and connect corridors around them so they can become anchor points for wildlife and biodiversity.” Meanwhile, some 600 miles northwest, fingers are crossed that Illinois conservationists can convince decision makers to save Bell Bowl Prairie, that state’s very own “sacred gem.”

NWF PRIORITY

Historic grasslands legislation

After years of effort by the National Wildlife Federation and its conservation, Tribal, sportsmen and other partners, the North American Grassland Conservation Act was introduced in the U.S. Senate this July. The law would kick-start voluntary protection and restoration of North America’s grasslands and the livelihoods and wildlife that depend on them by creating a landowner-driven, voluntary, incentive-based program to conserve and restore these vital ecosystems. “Grasslands are North America’s most imperiled ecosystems,” says NWF President and CEO Collin O’Mara. “This act will mark a sea change in how we conserve, restore and revitalize prairies for ranchers, hunters and wildlife alike.” See actforgrasslands.org.

Brianna Randall is a Montana-based writer.