by Kathy Andrews Wright
Before Mr. Shoub established his farmstead in the mid-1800s, much of Sangamon County was covered in tall-grass prairie, broken only by tracts of timber along rivers and streams and isolated prairie groves. The process of re-creating a tall-grass prairie began in 1995 when the Ostermeier family, owners of the land Mr. Shoub had originally farmed, allowed Lincoln Memorial Garden the use of 29 acres for a prairie restoration project that still blooms and flourishes 25 years later.
Thanks to a grant from the Illinois Department of Natural Resources (IDNR), three prairie sites—the front prairie, middle prairie and back prairie—were planted with a mixture of grasses and forbs.
“As staff and volunteers were working to develop the prairie plots nearly 25 years ago, some 40,000 plants were planted over the course of two summers,” explains Larry Miller, head gardener for Lincoln Memorial Garden. “Most of the grasses and forbs were placed in the middle prairie, which is the largest of the plots. Across the front prairie, between the road and historic hedgerow, a belt of forbs, or wildflowers, were planted with the intent that a strip of showy, colorful wildflowers, such as cup plant, compass plant and purple coneflower, would create visual interest for passersby.”
Considerable effort was expended in developing the wildflower strip, and a lot of hand weeding took place to remove invasive exotics, such as thistle. Today, little remains of that wildflower strip, evidence that nature does as it desires.
“At the onset, the front prairie had a nice stand of scurfy pea (Psoralidium tenuiflorum),” Miller recounts. “Today this showy, herbaceous wildflower, which reaches heights of two to three feet and produces blue-violet flowers from late spring through late summer, no longer appears in the front prairie, but it does in the middle prairie, where it was not planted.”
Obviously planted with a different mix of native prairie plant seeds provided by the IDNR, the back prairie—located west of the berm—developed into a high-grade sedge prairie, containing a diversity of these grasslike plants that have triangular stems and small flowers that lack the showy petals of wildflowers.
After 25 years, the prairie contains an assortment of grasses and wildflowers that keep the landscape colorful throughout the growing season. Today, the focus is on allowing nature to take its course on species composition and instead minimizing the presence of invasive, exotic plants, such as giant ragweed, hemlock, thistle and sericia lespedza.
“To maintain a nice diversity of the colorful forbs, we burn the prairie in the fall or later summer, as research has shown that early spring burns promote the growth of grasses over forbs,” Miller explains. “Controlling sericia lespedeza is our primary concern now and entails spot chemical spraying, prescribed burns and mowing the prairie in mid-August to prevent the plant from going to seed.”
Miller sighs, noting that each stem produces in excess of 1,000 seeds.
“We have been managing for sericia for six years and have made a noticeable difference in the number of plants and the area where it occurs,” he says. “It will probably be another 10 years before we can confidently reduce our mowing program and let the fall prairie bloom.”
Miller is excited about the Garden’s participation in cutting-edge research underway by a team of researchers from the Department of Environmental Studies at the University of Illinois at Springfield.
“Using drones, researchers are assessing the locations and severity of serecia plants on the Ostermeier Prairie and will produce a map that will minimize the labor-intensive, grid-pattern searches we now have to undertake,” Miller elaborates. “This technique is groundbreaking in the control of invasive species.”
Walk the paths of the reconstructed Garden prairie throughout the year to relish the ever-changing vista of the habitat that once covered much of the Prairie State. Take in the refreshing mint scent of the lavender-flowered, pollinator-friendly wild bergamot. Pause at the Prairie Observation Berm, binoculars in hand, to watch grassland birds swaying on the heads of cup plants while their melodious songs float across a sea of native prairie grasses. Give thanks to the visionaries who 25 years ago dreamt of a place where visitors could momentarily immerse themselves in what was once the prairie of Illinois.