Spring 2002

Classic oak woodland with prescribed burns provides for abundant native flowers and draws many birders during warbler season

DuPage County, Illinois

This idyllic suburban park with its resplendent wildflowers is a pocket wilderness, full of adventure and drama if you know what to look for.

As you hike into the preserve, keep your eyes on the big old trees, and you’ll soon notice that there are two distinctive forest types here. In the southern portion, where all the old trees are oaks, you’ll see a classic oak woodland. This part burned when the prairies burned for thousands of years, and the results are still visible here today. Here you’ll find such wildflowers as rue anemone, spreading dogbane, and purple Joe Pye weed. They thrive in the plentiful sunlight that filters through the oak leaves.

But in the northern portion of the preserve, which slopes gradually down toward St. Joseph Creek, there is an unusual mix of ancient trees. Bur, white and red oak are here. So too are black maple, walnut, butternut, and white ash. You won’t find rue anemone here, but you will find false rue anemone, squirrel corn, and Dutchman’s britches. These species can make do with a lot less light.

The mixed oak and maple woods is also a fire-dependent community (without fire, no oaks). However, it probably burned less frequently than the upland oak area. Studies by the Forest Preserve District of DuPage County conducted decades ago found that much of the grove’s richness was threatened by lack of fire. Buck-thorn was beginning to invade, mostly around the edge, but the more serious problem was sugar maple. "It’s now the commonest understory tree throughout all parts of the grove," says retired District ecologist Wayne Lampa, "even though there are few old ones. Its dense shade was eliminating many of the other species, before the District started to control them." For many years now the District has been conducting prescribed burns throughout the woods, eliminating buckthorn and thinning the sugar maples. The richness of the wildflowers has improved, and perhaps the balance will swing back to the black maples, oaks, and others.

At the north end of the preserve is St. Joseph’s Creek. It is spanned by a lovely wooden bridge called "Magic Bridge" by birders who flock here during spring warbler season. The creek winds through woodlands, making room for a concert of mid-season Virginia bluebells and a picture-perfect view of birds. Visitors may see gemlike spring warblers; and all year long there are downy and hairy woodpeckers, and northern flickers. Great horned owls are also regularly seen at Maple Grove. Jim Walser, Forest Preserve District ecologist, can’t forget watching a black-throated blue warbler taking a dust bath on the footpath ahead.

For thousands of years the Native Americans lived among the many hundreds of acres of the original Maple Grove. The Potawatomi tapped the maple trees here — "presumably they were black maples," Lampa says — and legend has it, they taught Pierce Downer the art. Downer settled the grove in 1832; thus the name Downers Grove. This remnant was bought and protected in 1920. Now it’s surrounded by houses, but there are no expressways nearby. It is surprisingly quiet.

A part of the open oak community was a picnic area from the 1920s until the 1980s, when the district stopped mowing. A few years later, a plant inventory revealed 100 species abounding, including two orchids. The plants had been there, hanging on around the tree trunks where the mowers couldn’t reach them but the sunlight could. Violets, Jacob’s ladder, May apple and trout lily adorn the area in spring; asters, pokeweed and woodland goldenrods in the summer.

Maple Grove is open daily one hour after sunrise to one hour after sunset. Leashed dogs and bikes are permitted on the trails. The preserve’s managers urge visitors to stay on the trail as the grove’s soil erodes easily if the rich plant life is trampled. Or help the District staff and stewardship volunteers who cut brush here on some weekends. — Alison Carney Brown

What is Chicago Wilderness? | Store | Donations | Contact Us | Home

Copyright 2006 Chicago Wilderness Magazine, Inc.
Revised .