Manipulating Nature

Here's an unusual take on restoration. Although I had a lot of involvement in walking this one through the process, as the chair of a working group with something like 17 stakeholders... the concept, and much of the design, were done by Dan Soluk of the University of South Dakota.

The overall concept was to restore breeding habitat for the federally endangered Hine's emerald dragonfly. At a couple of other nearby locations, that was done in fairly conventional ways. We found places where a water source was available, where things had been somehow modified, and we put them back to a functional level. I'll talk about those another time.

But at the site in the photo above, at Waterfall Glen Forest Preserve in DuPage County, Illinois, Dan found a way to construct an experimental system, one where graduate students will be able to manipulate flow rates and temperatures, and monitor effects on larval survival. That information, in turn, can be used to guide future restoration efforts.

It started when we visited a former fish farm recently acquired by the Forest Preserve District of DuPage County. A series of artesian wells had been sunk, and the groundwater fed into several ponds used to raise trout. One of the wells, the highest one up the terrain gradient, was leaking severely. A few dragonflies had been seen hovering over the streamlet flowing down over what was essentially a mowed grass lawn.

Early discussions on creating a streamlet with native vegetation quickly determined that we'd need to pipe the water laterally first, because there was a house and a septic field in the way of a natural gravity flow. Early in the conversation, Dan offered the idea of putting flow valves on the outlets of that pipe, and developing a system for field experimentation. It's rare to have such an opportunity, we couldn't pass it up.

I completed my nearby projects by early 2008, and moved on to other things. The work at Waterfall Glen had barely started then, so it was just this past summer that I finally had an opportunity to see what had been constructed from Dan's concept.

The rock basin in the photo is one of several intended to catch the outfall and prevent erosion. From there, the water overflows on the downhill end, on the right of the photo, and a small streamlet, 6 to 12 inches wide, a few inches deep, flows through planted wet prairie and into an existing marsh.

In the background, what was once a dense thicket of buckthorn has been cleared. The remaining trees show the effect of that recent past; where they had been shaded out, bare trunks reach for the sky. Eventually, perhaps the open woodland structure will begin to look more natural. The herbaceous understory is new, planted from seed, barely established. The ground had been fully shaded and almost bare at the start of the project. In the far background, the steeper bluff slope has also been cleared.

Initially, dragonfly larvae will be released into the new streamlets, and their three to five year aquatic development monitored. Probably, adult dragonflies from nearby natural habitat will also deposit eggs into the streamlets, if they're not intentionally screened from doing so. Eventually, the Forest Preserve District will redo the site, using the new data in the design of a more natural graminoid fen complex.

salvaging knowledge from loss

Much of my childhood was spent amidst suburban sprawl. Through the 1960s, my once low density neighborhood almost completely filled in with residential and commercial development. Soon I lived in an inner suburb, and the sprawl had progressed many miles outward.

Later, I would rebel against this sprawl. But as a grade school student, all I could do was ride my bicycle greater and greater distances to explore the remaining open spaces.

Most of these open spaces were part of the Cook County Forest Preserve District system. Set aside much earlier than most other regional districts, they were for the most part exactly what the name implied: They preserved forests. In my greater neighborhood, they existed as bands along the Des Plaines River to the west, and the Chicago River to the east. Some were recreational places, mixed lawns, picnic groves, and softball fields surrounded by oaks. Others were simply dense bands of trees, with an occasional trail. What open places there were would eventually, without management, also become forest.

For a while, there were some fairly large privately owned open places, and I spent a great deal of time on a few of these. I watched as, one by one, they were destroyed.

One special place was located a few miles from my home. It was on the east bank of the Des Plaines River, and between Route 58 and Central Avenue. A narrow band of Forest Preserve with a horse trail marked the eastern part of this several hundred acres of open space, but most of it was in private hands.

We called it Carle Woods. In the late 1940s, Orlando Park had taken his Northwestern University ecology classes there on field trips, and there were various animals in the collections of the Field Museum and the Chicago Academy of Sciences with that name on the tags.

Many years later, I would sit over dinner with Richard Edgren in his Woodside, California home, and listen to stories of those field trips. He had been one of Park's students, and he told me of the detailed collections undertaken, the small plots marked off, everything for several inches down removed and sifted through to characterize that square meter of forest floor.

But in 1971 and 1972 I had only a name, and the knowledge that in one of those museum collections was a wood frog collected a long time ago, with a tag that read "Carle Woods."

Carle Woods was a very special place, and I would often wander it for many hours. I came to know the place very well. Near the river, the trees were tall, majestic,and it was easy to walk beneath them. There was only leaf litter and a few wildflowers and scattered shrubs, and never any standing water. To the east, the trees became smaller and the shrub cover denser and walking more difficult, and each spring the ground would flood to a depth well above my knees. It wasn't just a pond; the entire eastern edge of the woods was one unending swamp. But by mid-summer, it would be completely dry. Once, in this vast wetland, I heard the elusive wood frog call. But I never saw it there.

To the southeast, the site opened up. Here a rail line passed diagonally through the county-owned part of the site, and a set of power lines. It was wet here too, a continuation of the wooded wetland, but this area was kept open by periodic late summer mowing. Here, I found snakes in abundance, of several different species. I also found frogs, chorus frogs and leopard frogs, species typical of open and sunlit shallow wetlands. One day I came face to face with a gray fox, both of us startled and frozen in place. A moment later it vanished into the tall grass.

One day Carle Woods was sold, and soon the new campus of Oakton Community College was built there. Parts of the woods were left intact, in the sense that trees still stood there. But they were now small and fragmented, a pathetic shadow of what had been. The once vast wooded wetland was drained and reduced to a couple of vernal ponds, perhaps 100 feet across. The more open parts in county ownership remained much as they had been, with small trees encroaching into some once open areas, other parts little changed.

In the mid-1980s I received an inquiry about a specimen I'd collected at Carle Woods and later deposited in the collection of the Illinois Natural History Survey. By this time I had a better understanding of habitat, and I delved into available information to learn more about the site.

I started with the General Land Office Survey notes, which laid out township and section lines (in the 1850s, in this case). Using plat maps and witness tree data from these, I was able to partially reconstruct, at a coarse scale, what this place had been like just after the time of Euro-American settlement. Then, I visited a local historical society, and found a wealth of more recent records... maps of crop fields with records of annual yields and types of crops grown, plat maps showing ownership.

Not long before this, I'd met Robbin Moran a few miles to the north at Ryerson Conservation Area, which occupied a similar landscape position on the east bank of the Des Plaines River. Reading Robbin's paper on the presettlement vegetation of Lake County, and walking through the woods with him and asking questions, I came to understand more about what these places had once been, and why.

In the mid-1800s, most of the land west of the river had been treeless prairie for as far as the eye could see. Frequent fires, mostly set in the fall right after the first hard frost by Native Americans, had burned to the river but usually were unable to cross it. The river acted as a firebreak.

Trees lined the east, or downwind bank. First there was a very narrow band of floodplain forest, often only a few meters wide. East of this was a mesic forest, dominated by sugar maple and basswood. This higher terrace flooded infrequently, but did flood in 100-year events. Soils were loose, well-drained. Early spring wildflower displays would have been impressive, and as late as the early 1980s spectacular beds of trillium and mayapple covered the ground.

A little more to the east, where fine clays and silts washed down from the adjacent Park Ridge Moraine had accumulated, the soils became nearly impermeable. This sticky yellowish clay held ponded water each spring, then in mid-summer it would become very dry. Stunted oaks grew around the numerous ponds. Eventually, moving east and up the moraine slope, the trees opened into savannas or prairies.

It was a remnant of this ecosystem I'd once walked through at Carle Woods. The impressive trees near the river were sugar maples and basswoods. The denser community to the east was northern flatwoods, with swamp white oak, white oak, and an understory of sedges and shrubs. It was in these vast flatwoods ponds that I'd heard, but not seen, a wood frog at Carle Woods. At Ryerson, I did see them, did catch and photograph a few, before they faded away there as well in the late 1980s.

At Carle Woods, the treeline had once extended well to the east, another quarter mile or so. There was sugar maple and red oak in the western part of the woods, and to the east white oak and hickory. The modern treeline followed straight lines and 90-degree corners, so it wasn't surprising that almost half of it had been cut. The fields had been farmed until the 1930s and 1940s, when the Forest Preserve District had begun to buy them one by one and allowed them to go fallow. The snakes I found had occupied the newly fallow fields; originally those species would have been in other fields, natural grasslands and wetlands, a bit to the east.

I wrote those findings up, documented how the treeline had shifted over time, documented how those snakes I'd found correlated with those habitat types. It was one of the first scientific papers I ever wrote. Although it remained unpublished, it was later cited by others.

That experience awakened me to the temporal dynamism of plant communities. What we see today often bears little resemblance to what once was on the same bit of land. But the clues are there, for the careful observer.

There was one more lesson yet to come. A few years later, the college "restored" a section of prairie on former farmland along Rt. 58. It was very close to the river, very near where those 1850s surveyors had marked sugar maples and red oaks as witness trees.

There had been no prairie on the land now owned by the college, at least not anytime in the past 150 years, except for a tiny triangle where their entrance road crossed west of the river. It was easy enough to check; a shovel in the ground at the edge of that "restoration" produced light-colored forest soils. To adopt regulatory jargon, they hadn't restored prairie... they had created it (or at least a simplified mimic of it) where forest had once been.

Ever since writing that unpublished paper in about 1984, ever since documenting how the landscape of Carle Woods had changed, my first step on any potential restoration site has been to reach an understanding of what had been there before... and why it had been there. Successful restoration is more likely when one works with ecological processes, instead of fighting against them.

the primordial beginnings

My brief bio at the end of an article I wrote for Chicago Wilderness Magazine (in 2003) reads "Ken Mierzwa grew up near remnant bur oak groves north of Chicago..." That place had much to do with my subsequent view of natural areas, and of restoration.

My first few years were spent in a quiet, tree-lined neighborhood on Chicago's north side, just off of Fullerton Avenue. As I reached the age of five, my parents moved to the northern suburbs, not very far from the city but at that time (1960) still semi-rural. There, I had my first taste of nature.

My childhood home was on the gentle western slope of the Park Ridge Moraine, a broad ridge of unsorted glacial till left behind by the Wisconsinan glaciation. The concentric moraine, perhaps a couple of miles wide and only about 40 feet high, roughly parallels the Lake Michigan shoreline through the northern suburbs until it abruptly disappears at the limits of the Chicago Lake Plain.

We lived about two blocks from the crest of the moraine. The high spot was marked by a few clusters of trees in what had been a golf course, and was later to become Maryhill Cemetary. At that time it was fenced but fallow and overgrown. One of those clusters of trees, right on the very top of the moraine, consisted mostly of bur oaks. The other trees were newcomers, aggressive pioneer species, fast-growing native species like cottonwoods. There were a few wet spots, most of them man-made... former golf course water holes.

Behind my house was a shallow marsh, which flooded over into our backyard each spring. Here I found my first wildlife; western chorus frogs and plains garter snakes. We found smooth green snakes under our porch the first year, but they quickly disappeared and we never saw any in the neighborhood again.

These are, of course, all prairie animals. Indeed, the empty land behind our house had once been prairie. For decades it had been farmed, and now it ran wild with weeds. There was one beat up old prairie remnant about six blocks to the south, although I didn't recognize it as natural until quite a bit later.

One day I ventured that two blocks to the cemetery fence, a major expedition for a five-year old. Skirting the marsh, I would have walked through successional fields and ducked through openings in hedgerows. In the second block, I entered what up to then had been terra incognita... a tree-shaded land of mystery, a straight dirt pathway wide enough for a car, the tall trees lining each side the same size, arching over and nearly touching to form a dark roof which at my small size, seemed vast and cathedral like. Today, I'd look at such a place and realize that the trees had to have been planted in such straight rows, and they must have all been planted at the same time. They probably weren't much more than 50 or 60 years old. But at that time, I saw only the magic of a new and mysterious place.

The pathway opened out into a clearing along the road, with an abandoned farmhouse tucked into the edge of the trees. We walked through the empty house, broken glass crunching under our small feet.

In front of the house, along the two-lane paved road which divided it from the cemetery fence, was a shallow rectangular pond. Peering into the water, I caught a glimpse of movement. Getting close to the surface and looking closely, I saw a creature of wonder.

It was four or five inches long, olive green, with a broad, flattened head. Reddish gills sprouted from each side of the head at the very back, waving gently in the water. It had four delicate legs, and a high tailfin.

I had just seen my first larval tiger salamander.

The other kids looked and grew bored and moved on to something else. Someone called it a "mudpuppy" which of course was not very accurate. But I was fascinated. Obviously, if I still remember it so vividly 49 years later.

Within a year it had all been destroyed... the pond, the old farmhouse, the magical shaded portal of trees that had led me to this place. It had all been replaced by another new suburban subdivision, setting the pattern of my younger years. I watched so many places as they were destroyed forever. Some of them were special places.

Within a year or two I'd discovered all the ways into the cemetery, all the gaps under or through (and later, as I grew bigger, over) the fence. With my friends, I explored it thoroughly. I'd found the shallow marsh just south of where I'd seen that salamander, a place were I watched northern leopard frogs each spring. A little to the east, toward the crest of the moraine, was a larger pond, straight-edged and obviously excavated. This was the easiest place to find tiger salamanders. Each mid-July, they came out of the water and paused for a few days under bits of plywood or other debris. At first they were mostly olive green, with red gill stubs. Over the course of several days they darkened, eventually becoming black. After the next rain they disappeared, only to be replaced by fresh ones, still green, still with gill stubs. I took a few home, kept them in terrariums full of dirt. They immediately burrowed into the soft earth, constructing elaborate tunnel systems. A few weeks later I'd dig them up, and they were deep black, with small yellow spots on the lower sides. This was how I learned that the field guides didn't always show accurate representations of the animals. There were no pictures of that transitional stage; only the olive green larvae, and the black and yellow adults, which had much more extensive mottling than the juveniles I saw each summer.

Beyond that pond there was another pond. To get there meant scrambling up a bit of a slope at the head of the excavation, onto the very crest of the moraine. The edge of the grove was guarded by brambles, but once through those the oaks closed overhead. A few more feet, and there was a pond unlike the others. This one had no straight sides, it was an irregular oval shape. Large oaks grew right to the edge, with a dense shrub understory. There was a mix of cattails and open water, and it was deeper than the other ponds. The salamanders were harder to find here, there were many more places for them to hide. But several times I was able to wait patiently on the bank, and eventually watch a larval salamander swim into view. Each time, it brought back memories of that first salamander.

By this time I knew a great deal about salamanders. Beginning in second grade, I'd read every book in the school library on amphibians and reptiles. Usually, I'd read each one several times. Paging through books by Roger Conant and Hobart Smith, I never dreamed that one day I'd meet the authors.

Tiger salamanders and oak groves were to become very important to me one day. At that earlier time, they ignited the spark that would lead to future learning.

catching up

Last month I attended the 3rd National Conference on Ecosystem Restoration, held in Los Angeles... the bi-annual event which originally inspired this blog about two years ago. It was perhaps slightly surreal to sit and talk about restoration in an upscale hotel in downtown LA, in one of the least natural places on the planet, a paved over semi-desert now covered by shiny glass and steel boxes. Yet, there we were.

The event was a little smaller this time, heavier on agency folks and lighter on corporate folks, a reflection of the current economic times. I was only able to stay for the first two days, because I was just off a Midwestern trip, and had deadlines waiting for me back at the office.

The key thing I heard at the event: Several folks in keynote talks saying that we're now in the third great wave of restoration. The first, they said, was early preservation efforts, the National Parks set aside by Teddy Roosevelt and so on. The second phase, the regulatory changes of the 60s and 70s, beginning with the publication of "Silent Spring" and with the surge of command-and-control laws which followed. The third... well, I heard several definitions, with the word sustainable thrown around a lot, but I'm not sure I heard one clear definition that stuck. That's so often the case in times of change.

More on that in a little bit.

end pause

I'm back, and gathering a few photos to post of past restorations. They should be up soon.