A living legacy of research at the UW Arboretum

University Place: Pioneering plant ecology project has broadened its scope over nearly a century

Scott Gordon
Prairie restoration has been a principal research focus at the UW Arboretum going back to its founding.

Wisconsinites know the University of Wisconsin-Madison Arboretum as a contemplative place to visit a plethora of gardens, prairies and forests — 1,200 acres of the Wisconsin Idea bordered by Lake Wingra to the north and sprawling urban development in other directions.

But the botanists and ecologists who created it were thinking more about rigorous scientific research and teaching — and above all, insights into how to restore ravaged environments — than they were about providing a naturalistic refuge for the public.

In the 21st century, nearly a century after its founding in the 1930s, the institution balances Wisconsin's tradition of ecological research with public outreach, citizen-science projects, and hosting visitors, whether they want to learn more about prairie ecosystems or just enjoy the scenery.

Established on what was previously farmland, the Arboretum was initially a place to study the inner workings of Wisconsin's prairies and recapture what the area's landscape looked like before European settlement. Over time, it grew to reflect plants and ecosystems from across the state.

The UW Arboretum is a popular destination in Madison for hiking excursions.

Brad Herrick, an ecologist and research program manager at the UW Arboretum, offered an introduction to its history and evolving mission in a July 3, 2018 talk for the Wednesday Nite @ the Lab series on the UW-Madison campus. In the talk, recorded for Wisconsin Public Television's University Place, he recalled the scientists who conceived of and launched the project, as well as the forces, both human and natural, that have shaped it ever since. 

Wisconsin's renowned early naturalist and scientist Increase Lapham first conceived of the idea of a university arboretum focused on native plants in 1853. However, the UW didn't actually begin purchasing land until 1932. The next year, horticulturist William Longenecker was hired as an executive director, and Aldo Leopold, then a professor of wildlife ecology at UW-Madison, was made research director. The UW Arboretum was officially dedicated on June 17, 1934.

Curtis Prairie is the oldest restored prairie at the Arboretum. It was the site of much of the early research in ecological restoration that still shapes the institution's mission today.

"It's the oldest restoration in the world because it's still ongoing," said Herrick of the Curtis Prairie. "It's constantly changing and we're constantly having to pull invasive species every year to make sure that it stays a high-quality prairie."

UW-Madison botany professor Norman Fassett conducted the first major research projects on what would later come to be named Curtis Prairie in the mid-1930s, experimenting with planting native grasses on the parcel of land.

A springtime late-afternoon in the Wingra Oak Savanna in the University of Wisconsin-Madison Arboretum

With help from a student named John Thomson, Fassett gathered sod and seed from across southern and western Wisconsin, transplanted them to the Arboretum and tracked their progress. After a year of research, they concluded that plants from a sandy prairie in Spring Green had the best success rates in their new home.

Ted Sperry, the Arboretum's first ecologist, was hired in 1936. One of the first prairie ecologists in the United States, he stepped up efforts to reestablish prairies, building on the lessons of Fassett and Thomson's experiments. 

The prairie is named for John Curtis, a botanist and Waukesha native who started working at the Arboretum in 1941 and served as UW-Madison's plant research director for 20 years. Curtis and a student, Max Partch, published an influential paper in the late '40s that examined how fire impacts the competition between bluegrass species and certain prairie plants.

They found that burning cut down on the prominence of Kentucky bluegrass and Canada bluegrass and allowed native prairie plants to spread. Prescribed fires are still an important tool in the Arboretum's management practices.

UW-Madison mycologist and botanist Henry Greene conducted extensive studies of the fungi species in the Arboretum. He collaborated with Curtis on research into the germination of prairie plants. This work helped to establish many of the finer technical points of planting a native prairie and ensuring its survival, from battling weeds to fostering the right soil conditions for native grasses.

Virginia Kline served as the Arboretum's head ecologist from 1975 to 1996 and conducted research on incursions into the Curtis Prairie by the invasive white sweetclover. Kline figured out that controlled burning in the spring was conducive to the sweetclover's biennial life cycle, setting back the growth of the plants but leaving them alive to seed later in the season. She implemented a new approach, waiting to conduct burns until after the sweetclovers had bloomed, which killed the plants before they were able to release seeds.

As the UW Arboretum entered the 21st century, Joy Zedler served as its research director for 18 years. Extending investigations into the role of invasive plants, she focused on why these species move in and how to restore the ecosystems they've affected, sometimes by harnessing the unique capabilities of native plants to make those ecosystems more resilient.

In recent years, researchers are renewing their focus on plants and ecosystems native to the Dane County area. One reason is related to ecological issues like attempts to recreate habitats like a northern Wisconsin boreal forest in the southern part of the state will inevitably be incomplete, and draw in invasive species like buckthorn and honeysuckle. Additionally, not all of the ecosystems represented in the Arboretum would naturally border each other, so researchers are placing more emphasis on ecosystems that flow together — for instance, a prairie next to an oak savanna.

Contemporary research at the UW Arboretum also extends beyond botany and plant ecology.

Recent projects include a study of ticks led by UW-Madison entomologist Susan Paskewitz, and the UW Urban Canid Project, which studies coyotes and foxes in the restored landscapes and surrounding cityscape.

The Wisconsin Department of Natural Resources is studying Wisconsin's bats, frogs and toads there. And Karen Oberhauser, the Arboretum's current director and renowned monarch butterfly biologist, studies the butterflies' migrations in projects that involve citizen science.

"For a long, long time, we were doing plant ecology research," said Herrick. "We have a really strong botanical, plant ecology background, and that's great and we will all continue that. But we also want to do more work with wildlife, with citizen science."

This article was originally published on WisContext, which produced the article in a partnership between Wisconsin Public Radio, Wisconsin Public Television and Cooperative Extension.