Wilderness in the 'burbs

Saving Thorn Creek Woods took hard work and a bit of luck

|  Story by Cindy Cain |


April Richards sat on a bench near Owl Lake on a summer morning, listening to sporadic banjo-like sounds. 

The short bursts of musical strumming noises were coming from green frogs that live in the lake within Thorn Creek Woods Nature Preserve

The sounds produced the kind of simple, relaxing moment that can rejuvenate visitors who trek through the dense forest to the lake. 

Richards, who jokes that she ‘speaks frog’ and will imitate them on occasion, is an interpretive naturalist for the preserve, which was almost lost to development decades ago.

But a stroke of “sheer luck” and a lot of hard work by a dedicated group of volunteers led to the preservation of 1,025 acres in the middle of a populated area on Monee Road, north of Stuenkel Road, in Park Forest and University Park.

If you visit the preserve now, you will see the Civil War-era church that was moved to the site and now serves as the Thorn Creek Nature Center. You can hike the woods, traverse the boardwalks, visit the lake, arrange to tour the historic farm and its garlic crop and view the massive oak and hickory trees that were left untouched by development. 

“It’s wilderness here in the middle of the suburbs,” said Judy Mendelson, who has been affiliated with the preserve since 1978 and now serves as chairwoman of the Thorn Creek Woods Management Commission. 

Thorn Creek’s roots

A squirrel climbing on a fallen tree at the site.

(Photo by Chris Cheng)

Thorn Creek Woods Nature Preserve would not exist today without two critical components of its history, Mendelson said. 

The “sheer luck” part was the fact that the acreage hadn’t been developed as World War II ended and the south suburbs started expanding. The site wasn’t developed because much of the land was devoted to woodlots for area farmers to harvest wood. 

Other portions of the site were protected by farms on the outer edges. And ravines created by Thorn Creek made development of the land more difficult. All those factors kept a wide swath of land mostly wild, Mendelson explained.

The second critical part of the preserve’s creation involved the people who cared enough to fight to preserve Thorn Creek Woods. A group inspired by the eco-warriors of the late 1960s came together to save the land and preserve it for generations to come.

This came on the heels of the creation in 1963 of both Openlands, a metropolitan conservation group formed in the Chicago area, and the Illinois Nature Preserve Commission, as well as a realization that prairies and woods needed to be preserved in Illinois or they would all disappear, Mendelson said.

Judy Mendelson talking near the site's nature center

Judy Mendelson, who has been affiliated with the preserve since 1978 and now serves as chairwoman of the Thorn Creek Woods Management Commission. (Photo by Chad Merda)

The volunteers who worked to save the Thorn Creek Woods were “very savvy” and they began a multi-pronged campaign to reach their goals, she added. 

“They got experts out here and discovered it wasn’t just the backyards of their houses that had this wonderful woods, it was like 1,000 acres sitting here intact.” 

At the same time, the group worked with local governmental agencies, including the Forest Preserve District of Will County and the villages of Park Forest and University Park, and convinced the entities to buy portions of the woods. 

They also created a special Thorn Creek Woods management commission made up of representatives from the Forest Preserve District, Park Forest, University Park, the Illinois Department of Natural Resources and Friends of Thorn Creek Woods.


And they applied for nature preserve status, which is a state designation that affords special protection for the highest quality preserves. That meant the land wouldn’t be a mixture of ball fields, soccer fields and nature. The idea was to preserve Thorn Creek Woods as one big natural area, Mendelson explained. 

The plan worked, and 500 acres were dedicated with a big celebration as an Illinois Nature Preserve in 1978. 

You’ve got to have Friends 

Looking up at the site's tree canopy.

(Photo by Chris Cheng)

The group that saved Thorn Creek Woods originally was made up of people who lived adjacent to the woods and saw how beautiful the land was, which made them want to preserve it. 

“They called themselves the Walnut Grove Gang initially, and then it became Thorn Creek Preservation Association and now it’s known as Friends (of Thorn Creek Woods),” Mendelson said.

The management commission was the first of its kind in Illinois and it was the model used to create and manage the multi-jurisdictional Old Plank Road Trail, which travels from Joliet to Chicago Heights. 

The group didn’t stop once the preserve was created.

“The efforts continued on and on and on and on,” Mendelson said of the Thorn Creek Woods protection plan. 

In the 1970s Friends battled to make sure the proposed Crosstown Expressway route would not cut through the preserve and that University Park didn’t expand into areas that would later be added to the preserve. 

“And the result is now today, we have over 1,000 acres, almost all of it is dedicated as nature preserve or nature preserve buffer,” Mendelson said.

Friends organization members continue to volunteer and raise money to improve the woods and the nature center so they can be enjoyed for years to come, she added.

Without the Friends of Thorn Creek Woods, none of what exists now could have ever been created or sustained, Mendelson said. 

“They’re continuing to be the backbone of this preserve,” she said. “In terms of financial support and in terms of volunteers they muster.”

They build displays, run programs, work on the trails and staff the nature center. It’s all part of the “gazillions of ways that organization has and continues to support” Thorn Creek, she explained.

Nature Center and farm

Looking up at the site's nature center.

(Photo by Chad Merda)

While the Friends organization was working to reestablish the preserve, a Civil War-era Evangelical Lutheran church was acquired by Park Forest and the village had an agreement with Friends to move the church to Thorn Creek Woods. Volunteers painted the building, put up displays and organized programming. 

The church was built in 1861 at the intersection of Sauk Trail and Cicero Avenue in Richton Park. It functioned for 100 years until it was sold to Village Bible Church, which is north of Thorn Creek Woods

The church was donated to Park Forest, which bought the 10 acres the church sits on now at 247 Monee Road, Park Forest. In 1974, the building was “hauled” through the woods to its current home, Mendelson said.  

The nature center, closed now due to the COVID-19 pandemic, houses displays of the preserve’s flora and fauna, and maps and scale models of the preserve. 

As Thorn Creek Woods grew, the state purchased a “hunk” of the preserve, which was a 20-acre farm on the northeast side of the woods. Judy’s husband, the late Jon Mendelson, was tapped to be the caretaker of the farm and the couple managed the site, raised chickens and grew and sold organic vegetables to benefit the nature center. 

“And then we discovered garlic,” Mendelson said.

The crop was easy to grow and, best of all, the deer wouldn’t eat it. 

The garlic crop is sold at the Park Forest Farmers Market on the third Saturday in September to raise money for the nature center. This year’s sale is set for 7 a.m. until noon, September 19, at the Park Forest Farmers Market, 152 Main St. 

Hike through history

The boardwalk at the site.

(Photo by Chad Merda)

Thorn Creek Woods features a 3.5-mile out-and-back natural surface hiking trail that goes over Thorn Creek and through woodland, floodplain forest and scenic ravines. The Thorn Creek Bridge serves as a wildlife hub, so it’s a favorite spot for visitors to pause to enjoy the views, said Richards who has worked for Thorn Creek Woods for six years and is a former Field Museum educator. 

Hikers can see the difference in the preserve from the more open area along the Nature Center Trail that was grazed by farm animals for many years to the thicker oak and hickory forest along the Woodland Trail that was left undisturbed because the land was devoted to woodlots, she explained. 

The prairie restoration plots near the nature center feature a wide variety of prairie grasses and flowers including big bluestem, northern dropseed, switchgrass, cream false indigo, lead plant, butterfly weed, spiderwort, purple coneflower, compass plant, evening primrose and more. 

The preserve’s trail system starts low by the nature center and then heads uphill because the preserve is on a moraine left behind by glacial deposits. The trail system rides on the “spine” between the valleys of both Thorn Creek and one of its main tributaries. The high point in the preserve is almost 900 feet, “which is high in Illinois,” Richards said. 

 “It’s undisturbed nature,” she added. “And that is what we strive for, to let nature do its thing and we’re just here to take care of it and enjoy it.” 

Visitors to the woods can see many species including southern flying squirrels, raccoons, opossums, deer, minks, skunks, foxes, coyotes, woodland birds, hawks, owls and shade-loving plants. And depending on the season, they can see a swollen Thorn Creek or one that is barely flowing.


“When you walk out onto the Woodland Trail you really see the difference,” Richards said. “It’s shady, there is no ground cover, the trees are giant compared to the ones closer in. It’s an interesting walk through history.” 

The preserve is home to white and swamp oak and hickory trees in the dry upland areas and red oak, black oak, sugar maple and ash trees in the steep-sided ravines. The creek floodplain features oak, basswood, slippery elm and black walnut species. 

Friends of Thorn Creek Woods has established a capital fund and is seeking donations to improve the trail system by adding boardwalks and completing a new trail loop that will bypass the old south bridge site, which was closed due to its deteriorating state and wet ground conditions.  

The trail system upkeep has been a collaborative effort with work by staff, youth groups, volunteers, AmeriCorps, community service groups, state workers and Forest Preserve District of Will County staff. 

Owl Lake

A frog poking its head out of the water.

(Photo by Chad Merda)

The Woodland Trail leads to Owl Lake and the Owl Lake Trail. 

“When the glaciers were melting a piece of ice broke off and sort of got stuck … and it melted and it formed a big lake,” Richards said. 

The lake, which also is called a prairie “pothole” because of the way it formed, has filled in through the years and it is now part marsh.

“It’s really beautiful out there,” Richards said. “It’s very quiet. We have wood ducks, green heron (and) it’s kind of a nice bird sanctuary.” 

The lake/marsh also is teeming with those frogs that Richards likes to imitate. 

Owl Lake Trail has a Wetland Trail spur that heads into a marshy thicket and a wetland overlook that is in an open area with beautiful views of the surrounding woods. 

One of the nicest features is that you can’t really see beyond the lake once you are out there, Richards said. 

“This is one of my favorite spots where I feel that I’m really away from everything because you can’t see any roads and it’s hard to hear civilization here because the nature sounds are louder,” she said. 


A scenic view of the trees at the site.

(Photo by Chad Merda)

For information on Thorn Creek Woods Nature Preserve and the Nature Center and the programs the site offers, visit tcwoods.org, email [email protected] or call 708.747.6320. 


(Lead image by Chad Merda)

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