Restoring a "biological treasure"

Orland Park resident and Cook County Forest Preserve site steward Pat Hayes is smitten with Openlands' ecological restoration work at McMahon Woods in Willow Springs, IL. She recounts "how beautiful the fall mist is on the ponds" as she recently came upon the site.

As a volunteer-expert who cares for the forest preserve's natural areas, she has reason to understand the significance of Openlands' work there. In a note to Linda Masters, Openlands ecologist, she shared that when Native Americans occupied this region, people could easily walk through the woods. The trees were widely spaced, the understory open, and the ground lush with wildflowers and grasses.

And if you dig a bit deeper, you'll find something very fragile and unique at McMahon Woods.

This site features a fen, which is an extremely rare type of wetland that is fed by groundwater. A healthy fen will support a diverse population of plants and animals. Their uncommonness comes from their water chemistry, which is rich in minerals.

The McMahon fen is home to the federally endangered Hine's emerald dragonfly as well as many uncommon fauna and flora. This dragonfly requires a unique wet environment containing ephemeral rivulets (small seasonal streams) to reproduce. Without Openlands' concerted effort to maintain its habitat, it will cease to exist.

The fen and surrounding area was also once Dan McMahon's home. His granddaughter recently described the area surrounding his farmstead as once full of orchards, and the family kept a few cows, chickens and a vegetable garden. Photos from this time reveal the site virtually devoid of trees and shrubs with the exception of some oak groves. Mr. McMahon worked for the Forest Preserve District of Cook County, and after his death the farm was given to the District.

In the intervening years, the 340-acre preserve became more wooded and by 2005 the area without trees had diminished from 95% to 23% representing a dramatic shift in the site's ecology in little more than a half-century and threatening the rare fen and all of the wildlife dependent on it.

The decline of this preserve was characterized by the encroachment of invasive plant species, the dwindling of native plant species and the erosion of the fen. Concerned for the health of the fen, Openlands started its work in 2008 with wetland mitigation money from the United States Army Corps of Engineers. Through the removal of invasive trees, the planting of large amounts of native grass and wildflower seeds, and long-term TLC, staff expects the fen to recover and expand.

So why do this work? There's a long list of reasons driven by science, ecology, and self-interest not to divert, deplete and pollute sources of clean and abundant fresh water.

But if science isn't compelling enough, consider the anticipated outcome poetically expressed by Linda Masters: "The subtle blend of open prairie and savanna habitats combined with the mingling of a seepy fen indicates that a restored McMahon nature area will be a diverse biological treasure." Or as Pat Hayes more directly expressed: Openlands' activities are "changing what was once a clogged up mess of wooded area" into something that's "awesome."

Maybe doing something that people find awesome is reason enough.

McMahon Woods and Fen are part of the Cook County Forest Preserves and are located at 107th and Willow Springs Road in Willow Springs, Illinois.