Steve Carpenter, Director Emeritus of the Center for Limnology and Stephen Alfred Forbes Professor Emeritus in the Department of Integrative Biology, and Susan Carpenter, Curator of the Wisconsin Native Plant Garden at the UW Arboretum are pictured with their dog Jasper on their restored 100-acre prairie in the Drift-Free Zone on August 25, 2022. Photo: Althea Dotzour
For more than four decades, Steve Carpenter has studied lakes as ecosystems in which all parts—from living organisms like fish and weeds to the mud found at the bottom of lakes—interact to influence lake health. He has a keen interest in what keeps lakes thriving and the threats to lake ecosystems that push them to such an extreme tipping point that the whole system collapses.
Susan Carpenter, on the other hand, has devoted most of her career to the earth. As the curator of the native plant garden at the University of Wisconsin Madison Arboretum, she spends her days caring for black-eyed Susan and blazing star, while monitoring and protecting native bees. , including the rare and endangered Rusty-patched Bumblebee.
Steve retired in 2017, after decades as a professor of limnology (the study of fresh water) and eight years as director of the UW-Madison Center for Limnology. Susan continues her work at the UW Arboretum, where she also conducts outreach and public education. But together the couple – they married in 1979 after meeting at UW – Madison graduate school – now also spend their time restoring and conserving 100 acres of prairie, creek and cliff in Wisconsin’s Driftless Zone – so called because the glaciers that shaped so much of the state never touched this region.
Their work in the field is at the intersection of their professional life and their personal passions.
The carpenters have been the stewards of this land – encompassing two cliffs, a wet meadow, a wood and a stream – for 20 years.
As a child, Steve spent his summers on his grandfather’s farm in Missouri. This helped foster his career as a lake ecologist and inspired him to protect and conserve species native to Wisconsin, including prairie plants that contribute to the health of wild places in the state.
The Carpenters donated the conservation easement to the Mississippi Valley Conservancy more than a decade ago. Steve — who even in retirement continued to write grants, collaborate with scientists in Madison and around the world, and accept numerous honors — is using the Blue Planet prize money he received this year to invest even more in the country. The award is given annually to individuals or organizations that have performed or applied scientific research to help provide solutions to global environmental problems.
“Oh, hey, I’m covered in botany!” Steve exclaimed after looking down to find a number of seeds hitchhiking on his clothes as he and Susan walked through the meadow they spent decades conserving. “It’s stick seeds!” he said, before Susan corrected him, “No, it’s desmodium.”
The couple were joined on the pitch by their dog Jasper. Jasper belonged to their late son, Paul, and the puggle was a special addition to the family. Jasper loves walking through plants and rolling around in puddles. Grasslands are particularly good at absorbing and storing excess water and contribute to flood resilience in vulnerable regions, an attribute that makes their restoration especially important as climate change contributes to higher rainfall.
Susan explained that she has found at least eight native bumblebee species on their property, including the elusive rusty spot. She pointed to bees weaving through blooming cream gentian flowers, then backing out of narrow flower openings, pollen in tow.
According to the Wisconsin Department of Natural Resources, before the arrival of European colonialists, Wisconsin had 2.1 million acres of native prairie. Today, less than 10,000 acres remain, and most of it is remnant grassland that is too small to realize all the benefits a grassland provides to the landscape.
Fire was an important part of grassland health, helping to eliminate invasive species, restore lost nutrients to the soil, and prevent woodland species from taking over, but European settlers largely eliminated this practice. The grasslands of Wisconsin once burned naturally as a result of lightning strikes or through the activities of Wisconsin Native Americans who conducted burns to manage the land and provide access to food. Today, carpenters carry out controlled burns on their land; the wet grassland can be burned every year, while their dry grassland burns every three to five years.
In late August, plants like Indian grass, New England aster and goldenrod are in full bloom on the prairie. Birds dive for insects. Mosquitoes swarm in abundance. A cool dampness settles on the land, as the setting sun peaks above the cliffs through the receding rain clouds. “Earth is just a big lake with a few continents floating on the crust,” Steve said. “The principles of limnology apply perfectly to the Earth system.”
Video by Elise Mahon, science writer at UW-Madison