Holding off the invasion

Groups work to weed Pioneer Park of non-native plants

Nobody likes a party-crasher: drinking too much, eating all the best food and generally getting in everyone else's way. The feeling is so universal in fact, it even holds true in the world of plants.

That's one reason the Naperville Park District set out in 2007 to restore Pioneer Park -- literally weeding out what it calls invasive, non-native species of plants and allowing the native Illinois plants to thrive.

Why is this important? "Burning bushes," one example of the invasive shrub types removed from the park, are often sought-after for landscaping and beautification. The problem, explained Peggy Pelkonen, project manager for the Park District, is that invasive plants crowd out the native plants and change the habitat for the animals that use the space.

"Because (invasive plants) are so aggressive and so adaptable, they drown out all the native species. So you don't get your ephemeral spring flowers or trillium coming up anymore because the woody plants have the advantage," Pelkonen explained. "Animals that would thrive on the native plants would move on elsewhere. Buckthorn and burning bush are shrubs, so native animals can't see predators as well, and it changes the balance of nature."

So while the invasive plants are making it hard on honey bees, frogs, toads and even owls and humming birds, they also allow non-native animals to thrive in an environment they would otherwise not have found to their liking.

Pelkonen explained that many of these invasive plants are spread by birds that eat berries and then leave seeds in their droppings as they fly around. "Every year, we've had to go back and remove the sprouts," she said.

Pelkonen says the district is about two-thirds of the way done with the renovation, which was made possible by a $31,000 grant from the Illinois Department of Natural Resources. But weeding a 26-acre park that is overrun with non-native species is no easy task.

Park District staff and a host of community volunteers have been busy combing through the park working to handpick garlic mustard plants and other unwanted species and later planting burr oak, black-eyed susans, goldenrod, Pennsylvania sedge, trillium and asters among other plants.

This fall, the Park District is hoping to add a controlled burn, actually setting fire to sections of the park at 1212 S. Washington St., Naperville, to help eliminate invasive plants. Pelkonen explained that this works because "native plants can survive a burn. Their roots are so deep into the earth that it doesn't kill them off. They've adapted that way for this area because there have been (natural) burns through this area periodically. Most invasive plants can't handle the burn."

Sue Omanson, community development project manager, coordinated the volunteers, who included Naperville Central High School science classes and groups from local corporations, such as Office Max and Infogix. While Omanson said she contacted some of the groups to ask for help, many groups contact the Park District looking for a service project.

Nick DiGiovanni, a science and biology teacher at Naperville Central High School, brought a group of students to help with the park for the past two years.

"I give them extra credit. It's bribery," he joked, adding that while some kids come out for the extra points, "they really enjoy it, and they know they're doing something good. I talk about the history of it and show them some of the plants."

Omanson explained that Pioneer Park is an ideal park for renovation not only because it incorporates woods, prairie and wetland habitats, but also because it's centrally located in town.

"It's just a great demonstration area for what those different habitats should look like," Omanson said. "We have the DuPage River Trail going through there. Every day, even in winter, there are people riding bikes or walking through the park. It's a good place to educate the public about these local habitats that we want to preserve and restore."

While Omanson said there are no plans right now to have formal tours of the park, she says it's "always a possibility. Right now, it's more a passive area of recreation to picnic, bike, canoe. We've installed several signs so (visitors) can educate themselves."