I finally spent some time walking through the new Tedesco Environmental Learning Corridor near the south end of the ISU Research Park. The area has been under development for the past couple of years and hasn’t been open for public use until recently. The last time I walked in the area was nearly 40 years ago on a hot summer day when the landowner wanted advice on some problems they were having with beavers, if my memory is correct. The setting was quite rural then. There was actually quite bit of wildlife along the small stream which flowed through a jungle of weeds, brush, and small trees. The beavers had the stream dammed up, and were no doubt flooding some tile lines that were supposed to be draining nearby crop fields. People weren’t too keen on it, but the wood ducks loved it. I knew that I was walking through the same area when I visited the new park, but boy have there been a lot of changes!
Invasive honeysuckle bushes and equally invasive canary grass had taken over much of land in the years since I was last there. A combination of increased rainfall in recent decades and increased runoff from extensive development in the area had caused the stream to erode deeply into the landscape. The invasive plants have now been removed and the entire area has been reshaped to better handle stream flows without excessive erosion. More than a mile of attractive paved trail, suitable for people with all levels of mobility, has been developed to provide access to the new park’s many features.
The conservation board staff and their contractors used bioengineering techniques and best management practices to gain control over the stream’s past extensive erosion. Several new oxbow wetlands were created that will absorb excess runoff after heavy rains and release the flow more slowly to the stream. Willow plantings protect some stream banks. Strategically placed root balls and logs, along with more familiar stone rip-rap, were used to stabilize stream banks in other areas after they were reshaped. The stone used was primarily granite boulders and cobbles just like those that wash out of the glacial till that covers our area. The stream now stair-steps down a series of stone riffles that reduce its tendency to scour more deeply into the landscape. Native trees have been planted in some areas. Seedings have begun to take root, but it may be several years before the prairie plantings become mature enough to give good summer blooming displays.
I noted several pairs of mallard ducks that had already discovered the new oxbow ponds. Red-winged blackbirds are already nesting in tall vegetation next to the ponds. A red-tailed hawk was hunting along the stream. A kingbird perched on a weed stalk waiting to ambush a passing insect, but tree swallows were also grabbing their share. A blue jay called from one of the trees. Some minnows danced through the clear water at the base of one of the stone riffles; no doubt enjoying the improved oxygenation and water quality already present. I saw deer and coon tracks near the stream, too. And that’s only a beginning. Wildlife numbers and diversity will increase as the new plant communities develop.
The conservation board will hold a grand opening for the Tedesco Environmental Learning Corridor on Friday, June 28. All natural systems change over time, but the restoration of this show place should slow the rate of change to a pace that the natural plant and animal community can better adapt to. I hope many readers will visit the area that day and often in the future. It will be fun to watch the changes as they occur.
Steve Lekwa is a former director of Story County Conservation.