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Restoring Site Ecology

We have had the great fortune to be planning a project on a previously developed site. The site is now a grassy knoll surrounded by trees with an abandoned road and remnants of power lines. Mid-size trees dot the site, mostly mid-size oaks and honey locusts. Walking the site I have seen turkey, fox, and deer. It always felt like a relatively natural site and what is more relevant is that I really hadn't considered the history of the site much other than there had been buildings there at one time. Another great fortune is that we have been working with Steven Apfelbaum of Applied Ecological Services who has recently toured the site with us. Walking the site and spending two days with Steve opened up my eyes to some of the issues underlying our landscapes. Steve first noticed the invasives that were in the understory of the surrounding forests and how they prevented the young hardwoods from establishing. Next Steve was able to determine that the bedrock was very close to the surface of the site from observing the root-ball of a fallen tree, the algae that was dried into a sheet in a mud puddle, and the plant communities living on the site. The soil gets very wet when it rains, and it dries out thoroughly when it is not raining. Only certain plants will grow in those conditions. Those oaks and honey locusts were planted from the old project and many of them were diseased due to the poor soil conditions. The site had been "leveled to make it easier to build and the topsoil was dumped down the adjacent hill. We could still see the area where this had occurred. Understanding that history and understanding the current conditions made me realize that we had more of a reclamation project on our hands than I had ever expected. It also made me realize that planting trees would require special care if we wanted them to survive for any significant period of time. I always knew that man's imprint on the land had had an incalculable impact, for example in its natural state Pennsylvania originally had no open spaces, only forests. Corn, coal, and cattle have shaped most of the landscape of Western Pennsylvania. Now with the new set of eyes Steve has given me I realized with greater clarity the extent of the changes we have made to the land and to natural systems.

Then we took a tour of the site, through site maps over time and looked at where the contours had been and were able to extrapolate how water used to move on the site. Wanting to minimize storm water infrastructure, Steve made the following comment, "I have never worked on a new building project, where if we restored the natural waterways and we were not able to have the capacity on site to handle all of the storm-water." That is quite a statement. So in other words it is man's intervention on the land that has caused the storm-water problem, and if we revert to the natural systems that were originally in place we have solved these problems. It seems like such an obvious point but somehow I think it has eluded a lot of us over the years, it has certainly eluded me! When I was a graduate student I had read about ecological planning in Ian McHarg's book Design with Nature. McHarg talks about analyzing the land for soils, erosion, surface drainage, bedrock and slope. He also looks at land for agricultural, aquifer, ecological value and where travel routes should best be located. When I left school and entered the work force I never participated in any site-planning that really used this approach. Steve's work is McHargian but with refinements and to be able to read the land of the site enough to know what a healthy site would look like was valuable information and suggested new layouts to us, that will shape and organize our design.

On the way to the airport Steve was telling me about an article that he has written for one of the upcoming issues of Science Magazine. The article describes how if soil is brought back to a healthy ecological state it becomes a huge carbon sponge. An ecological approach to climate change is something I had not considered before in projects. Imagine a grass roots movement where each landowner tries to restore ecological health to their land as a way to combat climate change. It is an idea I have heard from others, and do not yet fully understand...but I am working on it...so much to learn and so little time.