BLOOMINGTON, Ind. (AP) — Dunn's Woods, the historic heart of the Indiana University campus, is on its way to becoming the native, diverse Indiana woodland it was hundreds of years ago.

The out-of-control purple winter creeper, aka Euonymus fortunei, that had taken over the 10-acre woodlot was dealt a serious blow Wednesday. Volunteers attacked the persistent plant and other exotic invasive species in an all-day event that involved hand-pulling in some areas, and application of herbicide where winter creeper carpeted the ground and climbed trees.

Assisting were IU students, faculty and staff, members of Monroe County-Identify and Reduce Invasive Species (MC-IRIS) and Sassafras Audubon Society, and employees of Bloomington Parks and Recreation Department, EcoLogic and General Motors.

An $18,664 TogetherGreen Innovation grant from the National Audubon Society and Toyota helped fund the efforts in Dunn's Woods and at Bloomington's Latimer Woods Park, just south of College Mall.

The Dunn's Woods Project aims to restore the iconic woods to the natural ecosystem it once was, populated with plants that evolved in south-central Indiana and provided a diverse habitat for birds and other wildlife, insects and microbes. The project was kick-started two years ago with a $10,000 IU Office of Sustainability Development research grant.

The woods have been a walk-through route on the campus for more than a century, and are regularly used as an outdoor classroom.

Recently, the woods have been used for academic research, including studying best methods for restoring an area packed with exotic, invasive plants into a native Indiana woodland.

That's biology doctoral candidate Jonathan Bauer's dissertation project. He has been hand-pulling winter creeper in some research plots in the woods for years, but he also helped with Wednesday's spraying.

Bauer is also propagating thousands of native plants in greenhouses in the IU biology department's Jordan Hall, plants that have been and will be planted in Dunn's Woods.

In one small area that had been hand-cleared of invasives, a patch of cardinal flowers that Bauer planted last November is 5 feet tall. An aggressive hummingbird is guarding the plants' brilliant red spikes.

"The stand of cardinal flowers provides proof of the impact of restoration, that a diverse, native plant community could be reestablished," said biology professor Heather Reynolds, who is active with the project. "It also showed us the labor involved in hand-pulling would be completely overwhelming."

Storms in 2011 knocked down or otherwise severely damaged more than a dozen big, old trees in Dunn's Woods and left gaping holes in the forest canopy. Winter creeper and other exotic plants thrive in such landscape disturbances, especially where they already have a good foothold.

That was a setback to efforts to eradicate the persistent plant through hand-pulling, Reynolds said. She's generally not a fan of herbicide use, but the winter creeper in Dunn's Woods warranted it.

"Applying herbicides is like chemotherapy," she said. "When a system is in bad shape, sometimes it needs chemical treatment to recover. Here, the euonymus is so dense, so thick."

The active ingredient the group used on the winter creeper is triclopyr, said Ellen Jacquart, who is a native plant specialist and founder of MC-IRIS. The herbicide kills broadleaf plants, including winter creeper and honeysuckle, but not grasses or sedges.

Reynolds said volunteers have been uprooting euonymus regularly for 12 years. But those efforts were simply not adequate "on an infestation this dense."

She said she hopes Wednesday's combination of spraying and hand-pulling will "get us to a place where we can use nonchemical treatment" to keep winter creeper out of the woods.

She noted that none of the exotic invasive plants targeted for elimination are inherently "bad." They're just in a place where they don't belong.

"It's not the plants' fault they're here, but rather human activities that have created the invasive species problem," she said. "We're trying to remedy a problem that our own species has created."

Winter creeper was planted as a ground cover on campus in the 1950s, long before its invasive nature was perceived as a problem and long before the importance of native plants was appreciated.

Reynolds said she hopes restoring Dunn's Woods will create awareness not only in students involved in the project, but also in those who walk through the woods.

Some may have never seen a truly natural Indiana forest, with its richly diverse understory of native plants.

And she hopes the project will contribute to shifting consumers' landscaping preference to one that favors Indiana's own plants.

In areas where winter creeper was hand-pulled, native plants are being transplanted, a project that will continue throughout the woods.

But no native plantings will occur until next spring in areas recently sprayed, where winter creeper blanketed the ground. A second application of herbicide might be necessary in a few months to completely knock out the persistent plant.

Hand-pulling of winter creeper will continue where it shows up.

"If you pull without replacing (with a native planting), you'll leave a gap, and an invasive will fill in," Reynolds said.

In addition to cardinal flower, native plants already thriving in the reclaimed woods include calico beard tongue, great blue lobelia and downy wood mint, the volunteers said.


Information from: The Herald Times,