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It was an odd geological formation to find in the woods. A small stone sat perched about two inches above the ground supported on a column of soil near a tree in Peoria's Singing Woods Nature Preserve, high up on the bluffs that run parallel to the Illinois River. It looked like a straight adobe mushroom stalk with a tiny stone cap.

This formation results when raindrops impact bare soil causing it to loosen and wash down a slope. Soil immediately under the pebble "umbrella" is protected from direct hits and therefore remains intact, supporting the stone as surrounding soil subsides.

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exposed tree roots on eroding slope

How much erosion does this little soil stalk represent? If you consider that a sixteenth-inch layer of soil, the thickness of a dime, spread over just a single acre amounts to five tons or more, you can begin to appreciate the magnitude of loss in a single year. It was shocking to learn that forest preserves could be big-time contributors to the siltation of the Illinois River.

The Illinois River gently winds some 300 miles from Chicago to St. Louis. Its watershed covers more than 30,000 square miles, including half of Illinois and parts of Wisconsin and Indiana. If you live in Illinois, odds are you live within the watershed of the Illinois River, which contains some of the best agricultural land in the world. It also hosts some of the most industrialized and urbanized land in the United States. These types of land uses tend to result in run-off, hence erosion and siltation.

The river has been monitored and studied for many decades. It's been estimated that between 1903 and 1978 sediments accumulated throughout its length at an average of about a half-inch per year. The rate has gone up in recent decades coinciding with an increase in row cropland of 67 percent, which occurred between 1945 and 1976. The 60 backwater lakes along the river have average volumetric losses of 70 percent since 1903. As of now, this river receives an equivalent of 17,000 truckloads of silt each day. This has long been attributed to agricultural practices and urbanization, but now we know there's a lot more to it than that.

We need to stop thinking of the river as where the water happens to be when it's not raining. Whatever we do within the watershed impacts the river. The rain that falls in all of our yards will sooner or later transport our soil, lawn care chemicals, etcetera, downstream. We are all, in a manner of speaking, tributaries.

But as we've now learned, some times it's what we don't do within the watershed that causes a problem. The Singing Woods Nature Preserve, unfortunately, provides a glimpse of some thing observed throughout the Midwest. Extensive areas within the preserve have no herbaceous plants to

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protect the soil. Water runs off quickly carrying soil with it. The large volume and velocity of water add to the problem of entrenchment erosion in gullies, and thousands of tons of soil can be carried to the river from a single wooded park.

Why are our natural areas and forests (supposed bastions of stability) culprits, contributing more silt per acre than most cropland? That question propelled the staff of the Peoria Park District into more than a decade and a half of ecological studies and consultations. It developed into a major project involving hundreds of volunteers doing what sounds like vandalism: setting the woods on fire and cutting trees.

To understand why these seemingly extreme measures needed to be taken, it is necessary to under stand how the missing soil around our little stalk and pebble were exposed in the first place. And it is also necessary that our constituents understand the severity of the problem.

The Problem on the Prairie

It actually started about the time of the Civil War; the vast tallgrass prairies of Illinois had been pretty much converted to agriculture. Gone was the expanse of wildflowers stretching to the horizon, the sea of prairie grass, the essential fuel for prairie fire.

Fires had swept from the prairies and burned through the oak-hickory woods of the Illinois River bluffs for millennia. Grasses and flowers in the oak woods are much shorter than those out on the tallgrass prairie, providing less fuel. In fact, contrary to the Bambi image, the flame height of a forest fire in the Midwest generally is low enough to step over. Crown fires that burn up into the treetops as in Yellowstone are virtually unheard of in this part of the country.

These forest fires were small, but their impact was huge. Plants that adapted to the occasional toasting of a fire thrived. Examples include oak, hickory, hazelnut, yellow star grass, birdfoot violet, and curly grass.

Those with little tolerance for fire tended to grow in bottomlands, and more moist (hence less frequently burned) sites. This included such things as sugar maple, ash, paw paw, bluebells, and sassafras.

With the loss of the prairies, fires moving across the forest floor have now become as rare as prairie orchids. The result of this inadvertent ecological change has been nothing short of catastrophe to the oak-hickory forest community.

Maple trees are intolerant of fire, particularly in the seedling and sapling stages, and they also are extremely prolific. Without fires to kill back the young trees, maples have moved steadily into the up land forests completely dominating the understory, with as many as one seedling per square foot, or over 40,000 invading maples per acre of oak woods.

The problem is its dense shade, as anyone who has tried to grow grass under a maple tree can attest. This results in a situation in which entire native plant communities are unable to survive. They die back leaving vast expanses of forest floor bare of vege-

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violet birdfoot at restoration site at robinson park photo by Mary B. Goodner

tation and exposed to erosion. Even oak and hickory trees are unable to regenerate under the gathering darkness of maple shade. The seedlings sprout but starve for lack of adequate light. The entire process has taken a century and a half and is observed throughout Illinois and the Midwest.

Without protective plants, there are now wooded slopes with exposed tree roots and little stones up on pedestals. As soil washes down to the river, it takes along nutrients and microorganisms that play a crucial role in the health of the entire forest community. Since it can take as much as a thousand years to grow a single inch of woodland soil, this loss essentially is permanent. We have a problem.

The Nature of Things

But it's not just the loss of soil that drives restoration. Woodlands here in Central Illinois are unique in the world. Totally surrounded by prairie, they have become adapted to conditions of light and fire. Nowhere else does this particular mix of species exist.

lady slipper orchids

The oak and hickory forests of Central Illinois are comprised of more than a thousand species of vascular plants, of which only 50 or so are trees. This complex community of species has developed what could be thought of as floristic wisdom. They have spent the ages learning how to deal with the conditions peculiar to this region. For example, they know that water evaporates here at a much more rapid rate than it falls from the sky, therefore they tend to be stingy with it, not allowing it to run off slopes. They've handled drought. The deep roots of herbaceous plants don't compete with and stress the shallow roots of canopy oaks and hickories, as maples do. They function as a community.

What they are particularly good at collectively is producing "biomass" under widely varying conditions. Biomass can be thought of as stuff such as leaves, flowers, stems, roots, fruits and seeds. It often is measured in tons per acre per year. In other words, biomass is good at capturing carbon from the atmosphere. All this stuff serves as a thatch to bind and hold soil in place and protect it from washing away.

In order to protect the landscape, restoration technique varies depending on the

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problem. For example, if maple seedlings cover the floor of an oak forest, it may be as simple as running a fire through the woods every few years in November, in order to kill back the maples. If, however, maples are so well established that there is virtually no fuel load (biomass) than it may be necessary to cut or girdle them in order to get sufficient light to stimulate plant growth.

In some sites, the problem is exotic invasive herbaceous plants, such as garlic mustard. It may be necessary to apply herbicide appropriately to kill back the invasive plant in order to maintain diversity.

"Prairie" is a French word meaning "grazed meadow" which is what the first Europeans saw when they first discovered the rolling grasslands covered with wildflowers and grazed by thousands of bison, elk, and deer. In the wetter regions, including Illinois, it was known as "tallgrass" because the grasses and forbs grew up to 10 feet in height. — Grand Priarie Friends, www.prairienet.org/gpf/homepage.html

The Human Factor

Besides loss of soil and loss of species, we also have been dealing with the problem of propriety. Human action, according to some, can only deteriorate nature. Therefore the areas that were most natural (wilderness for example) were those with the least human influence. Nature preserve management in this view is an oxymoron.

In Peoria, we had followed a hands-off philosophy toward natural areas stewardship, but had come to understand that by continuing our laissez faire approach we would be presiding over species loss and erosion. We had to change our point of view.

As we were getting more and more involved in active nature preserve management an interesting article, "Amid Insult and Injury, Urban Forests Hang On," appeared in the science section of the New York Times on Tuesday, Nov. 12, 1991. It carried a statement that certainly applied to us:

"...an emerging new paradigm sees humans as an integral part of nature, and nature itself as being not in balance but in continual flux. Humans, in the new paradigm, are just one of many forces contributing to the flux."

Ecological restoration, in this new point of view, gets us humans off our high horse. We are, after all, only one of many influences on the landscape, albeit a rather major one. It is crucial that we make our impacts more positive, in order to direct our influence toward ecological stability.

But there are some who don't necessarily adapt to change, whether it is as commonplace as a shoe style or as highfalutin as a paradigm. Restoration projects have not been without controversy.

"If you start with the assumption that all we can do is harm nature, then of course all we can be is vandals," aptly wrote Dr. William R. Jordan III, founder of the Society of Ecological Restoration and director of the New Academy for Nature and Culture, in an edition of the Prairie Roomer, a newsletter of the Poplar Creek (Illinois) Prairie Stewards.

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These photos show a ten-year span where maples were removed along Possum Path at
Forest Park Nature Center. The resulting plant growth has been dramatic.

Nature Restoration Foes and Fans

Don't be surprised if you can't please everybody. There could be some objections raised. It may be a philosophical issue as to the appropriateness of management in natural areas, but more likely, the seriousness of problems that call for extensive use of controlled burns and tree removal are not obvious to everyone.

To solve the latter, involve the public every step of the way. For those who are just against restoration in principle, you may never get them on your side. You just need to accept that you can't please everybody all the time.

By restoring the ancient context of light and fire, volunteers in Peoria have witnessed the revival of an incredible woodland flora in several locations along our wooded bluffs, literally rising from the ashes. As a result, soil is being kept out of the river.

Soil that once was bare and eroding has become covered by plants with such names as New Jersey tea, poverty oats, seneca snakeroot, and blue-eyed grass. A plant that has become surprisingly rare in Illinois oak woods has also returned, the oak seedling. They've just been waiting for the proper conditions.

It would be wrong of us to sit by while our forest preserves muddy the waters.

But you don't have to know the names of the dozens of varieties of wildflowers that have made a comeback; you can easily see the difference between restored woodland and what is normally seen throughout Central Illinois. There actually are plants growing beneath the trees! In effect you are looking at a vignette of what Illinois woods used to look like.

It is ironic that maples shading the forest floor contributed to the loss of soil around our little stone on a pedestal. Now that same soil is contributing to the turbidity of the Illinois River and in turn is blocking sunlight thereby preventing growth of aquatic vegetation. All things are indeed connected.

Conservationist Aldo Leopold (1887-1948) assures us in his Land Ethic from The Sand County Almanac, that a thing is right when it promotes the integrity, stability, and beauty of the biotic community. It is wrong when it does otherwise. It would be wrong of us to sit by while our forest preserves muddy the waters.

Dale Goooner is the supervisor of environmental and interpretive services for the Peoria Pork District. His article "Service is not Servitude, "was published in the May/June 1999 issue of Illinois Parks & Recreation magazine on page 19. Goodner can be reached at 309.688.3667, ext. 241.

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Burn Day Diary Entry

By Mike Miller

The day is here. All staff and volunteers have come together. Final equipment checks show that all is ready. The crew briefing has familiarized all of the crew members with their duties this day. So far looks good. The weather conditions are cooperating. The prescription called for the burn to take place prior to an approaching cold front.

This would give us steady and constant south winds. We travel to the site of the burn. Everyone walks the firebreaks for one last check and to become intimately familiar with the burn unit. Throughout time we are monitoring weather conditions with both a weather radio and onsite weather kits. We receive our first bit of bad news.

"The wind has shifted to the southwest." Our weather monitor informs us over our radios. That's OK though; our perscription and ignition plan has taken into account winds from this direction. "The wind speed is increasing to 10 miles per hour with gusts of 15." Again we are still within our prescription. "Relative humidity has dropped from 40 percent to 30 percent in the last hour."

There is a slight sound of unease within her voice this time. We all stop and regroup. We climb the ridge to our best vantage point and all eyes turn to the northwest. There, off in the distance, the horizon is filled with clouds billowing up like far off mountains. The cold front is a full day ahead of schedule and looming in the distance. The weather radio confirms our fear. Winds will increase throughout the day and shift from southwest to northwest by late afternoon Inching sustained speeds of 25 miles per hour. Scattered severe thunderstorms will develop by mid afternoon with strong and variable wind gusts. We all sit down at the edge of a tiny hill prairie. The fire leader utters the final word. The phoenix will rise... just not today.

Mike Miller is chief naturalist for the Peoria Park District.

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