Ferson Creek Fen Restoration
Rebuilding the Fen – One Sedge at a Time
Ferson Creek Fen Nature Preserve is a state designated nature preserve that is home to a diverse and conservative native plant community. Fens rely on groundwater input and are peat-forming wetlands, requiring thousands of years to develop into this niche habitat! The unique habitat-type makes Ferson Creek Fen a hotspot for biodiversity.
Although this nature preserve was dedicated as a high-quality site 30+ years ago, it has been severely degrading over the years as a slew of aggressive invasive species have significantly impacted the overall landscape including Hybrid cattail (Typha x glauca), Reed Canary Grass (Phalaris arundinacea), Purple Loosestrife (Lythrum salicaria) and Yellow Flag Iris (Iris pseudacorus). These invasives, which have the ability to completely take-over acres of natural area, form a complete monoculture and choke-out the native plant community. When this occurs, the site no longer possesses habitat or host plants for local wildlife, major erosion events occur along the Fox River and Ferson Creek shorelines, and the site loses its ability to be a functioning ecosystem. As well as herbaceous invaders, there has been substantial woody encroachment that has fragmented the site making management of these areas, especially the use of prescribed fire, a tough task. Woody and herbaceous invasive encroachment coupled with a management regime that lacked aggressive control of these species lead to the majority of the site becoming severely degraded.
View of the boardwalk in 2012. See the dense monoculture of invasive cattails that inhibited any native flora or fauna from thriving.
Rebuilding the Fen
Degradation was at its worst in 2016 when 85-90% of the fen habitat had become severely degraded. What can be done to recover from such a state? In, the St. Charles Park District ecological restoration crew implemented an intense ecological management regime to combat the invasive species and begin its restoration, which is a long-term commitment that involves thousands of hours of hands-on work and year-round management. To restore the degraded areas, the crew applies herbicide at the appropriate time to best control the invasive species. This initial herbicide application can take up to four site visits to achieve the desired goal of eradication. Once the invasive species has been sprayed out the area, it is then prepped for a restoration planting. At this stage the remaining dead vegetation is cut down through the use of clearing-saws (basically a weed whip with a circular saw blade rotating at the base). Once the area is prepped, it is then planted with native plugs (mostly sedges) to revegetate the area with the appropriate plant community.
Since inception of the restoration strategy, staff and community volunteers have planted more than 50,000 native plant plugs back into the landscape! Many of these planted plugs were grown in the naturalist’s in-house propagation area. Once the area is planted, it continues to require detailed herbicide management for several years to allow the area to revegetate and prevent development of the invasive species. This process will take roughly 5-10 years of intense restoration management and follow-up herbicide work to convert it back into a good quality rating. These restored areas are home to hundreds of native plant species that set the stage for local wildlife to once again thrive along the Fox River and throughout the community’s natural areas.
After site restoration…diversity in the plant community!
Park District staff and volunteers have been working on this project for more than five years, making stellar progress in restoring this nature preserve. As a result of their dedication, you may now view a significant increase in the number of wildflowers, observe threatened plant species and plants of concern, see numerous wildlife species return such as the Queen Snake (Regina septemvittata), and witness an overall resurgence of a once extremely high-quality natural area.
Visit soon! Take a hike and watch as the landscape continues to change for the better for years to come!
Be on the lookout for…
Blue Flag Iris (Iris versicolor)
Tufted Loosestrife (Lysimachia thyrsiflora)