Jeff Miller-UW Madison
Hotchkiss: “Ideally, public outreach should be paired with cutting-edge research.”
Katie Laushman remembers her first encounter with Amynthas agrestis. It was 2014, and the UW-Madison graduate student was working on an oak savanna habitat restoration in the UW Arboretum when a work crew member asked if she’d heard about the gardens’ newest inhabitant. He took Laushman over to a mulch pile and brushed away the top layer to reveal a bunch of writhing, wriggling earthworms.
“I didn’t know what to think of it — it’s a weird worm that jumps,” Laushman says. “I didn’t know that it would dictate my life for the next four years.”
Amynthas agrestis, also known as “crazy worms,” “snake worms” or “jumping worms,” is an invasive species in the U.S. believed to have arrived from its native Asia via potted plants or soil imported for landscaping. Also called “Alabama jumpers,” the worms established populations in the southeastern part of the U.S. over the last 50 years, but were not seen in the upper Midwest until 2013, when they were discovered in the Arboretum.
It’s never really a “good” thing to find a new invasive species in an environment — they tend to disrupt nature’s delicate balance — but the discovery presented a good opportunity to study the spread of a non-native species from the very beginning. At the time, Laushman was looking for a master’s project, so she teamed up with an advisor, UW-Madison botany professor Sara Hotchkiss, to study how the invader would impact the Arboretum ecosystem.
“Our concern with jumping worms is that it could potentially devastate forests through eating leaf litter, changing the soil and leading to lower establishment of diversity in native plants,” Laushman says. She set up about 70 plots across the Wingra and Gallistel Woods and conducted population surveys, drawing the earthworms out using a solution of water and mustard powder. “It agitates their skin, and they all kind of erupt to the surface,” she says. “Then you can see what species they are and how many.”
Research on jumping worms is one of the most important areas of study right now at the Arboretum, says Brad Herrick, Arboretum ecologist and research program manager. But it’s hardly the only topic being investigated. At any given time, there are dozens of research projects happening inside the Arboretum, on such topics as climate change, forest restoration, invasive species, pollinators and parasites. “When people think of the Arboretum, they don’t usually think of research — they think of recreation and educational opportunities,” Herrick says. “But really we are a center within the Office for the Vice Chancellor for Research and Graduate Education, so one of our main goals is to do research — and we definitely want people to know what we’re doing and how it may impact lives.”
Bryce Richter-UW Madison
Herrick: “We want people to know what we’re doing and how it may impact lives.”
For researchers, the Arboretum provides an opportunity to conduct fieldwork in a 1,200-acre natural area integrated within an urban center — a type of ecosystem that’s becoming more common as cities and populations expand. It’s also more convenient (and more affordable) than driving to remote natural areas. “The great thing about the Arboretum is that it’s a place that’s known really well — it’s been studied for a long time,” Hotchkiss says. “It’s a place where we can see change clearly.”
With so many eyes on the Arboretum, new scientific discoveries are inevitable. It was the site of Wisconsin’s first recorded deer tick in 2010, and the state’s first recorded lone star tick in 2013. Susan Paskowitz, an entomologist at UW-Madison, has tracked the tick invasion over the years, but more recently she’s been investigating ways to control the spread of lyme disease. In a study involving mice — a common host for deer ticks — she found that providing mice with nesting materials treated with pesticide was an effective way to decrease infections and the overall number of ticks. The study is ongoing; this year she plans to tweak the project to achieve even greater tick reductions. “We’re looking to see if we can make recommendations on how to do this on the scale of the average urban yard,” she says.
John Pauli, an associate professor of forest and wildlife ecology at UW-Madison, is principal investigator on a project studying the effects of climate change on the subnivean layer — a microclimate between the soil and snowpack that provides a home to species like wood frogs, porcupines and ruffed grouse. “Where a lot of ecologists have focused on above the snow — and the big, charismatic animals that live there — what we’re really interested in is how altered conditions will affect the microclimate in between,” Pauli says. “Really what this project is doing is trying to experimentally predict what life underneath the snow is going to look like into the future.”
He and his collaborators maintain three “programmable” greenhouses in the Arboretum (and at eight other sites throughout the Midwest) that can be manipulated to specific temperatures and moisture levels. The project is about halfway finished, but findings so far are helping researchers understand how the subnivium forms and reacts under different conditions.
Pauli says sites like the Arboretum are “priceless” — collaborations between university researchers and Arboretum ecologists are mutually beneficial, and people visiting the Arboretum for recreation can observe and engage with research. “These are greenhouses that people can look at,” Pauli says. “We don’t want them to touch them, but they can see some of the leading-edge science and better understand what climate change means for Wisconsin.”
There are few restrictions on the type of research projects Herrick approves at the Arboretum, with permits granted based on what space is available and what other projects are going on at the same time. But the research must have at least some tie-in to the Arboretum’s larger mission of land management and restoration ecology — the practice of renewing and restoring damaged or destroyed ecosystems and habitats with interventions ranging from erosion control to the reintroduction of native species and the elimination of invasive species.
At its core, restoration ecology is about the intersection of science and people, Hotchkiss says.
“The Arboretum’s mission is oriented toward the interface between how we live and how we handle ecosystems,” she says. “And ideally, public outreach should be paired with cutting-edge research. There’s no reason that research has to be watered down in order for people to participate.”
This story is part of our Arboretum Issue. Read the rest of our Arb coverage.
