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Unearthing the History of the Preserves

An Interview with Paula Porubcan Branstner, Field Station Coordinator, Northern Illinois Field Station, Illinois State Archaeological Survey.

What work is the Illinois State Archaeological Survey doing in the Forest Preserves?

In 2015, ISAS began implementation of the archaeological resources portion of the Natural and Cultural Resources Master Plan. Our primary focus has been on fieldwork, on the identification of archaeological sites within the Preserves, identification of the condition and significance of those sites, followed then by providing recommendations for the management and protection of this resource type. As of 2014, less than 20% of the Forest Preserves’ 70,000 acres had been systematically or professionally investigated for the presence of archaeological sites. In 2014, we knew that about 550 sites had been recorded already within just that 20%, meaning that hundreds of as yet undiscovered sites were likely present in the Forest Preserves. Simply put, resources – of any type – cannot be protected if we don’t know where they are. Our work in 2015 and 2016 has uncovered an additional 60 new sites within about 1,500 acres of new areas surveyed. We have also revisited over 50 of the most important, previously known sites in the Preserves in order to assess their condition and identify any current threats to this resource. Threats include things like erosion, various recreational activities, vandalism and looting, and planned development projects.

Why are there so many archaeological sites located in the Forest Preserves?

To date, over 1,200 archaeological sites (dating from 10,000 B.C. through to World War II) have been recorded in Cook County. More than half of these sites are located on Forest Preserves lands. Archaeological sites are concentrated in the Forest Preserves for two reasons. First, the 70,000 acres of Forest Preserves holdings are in areas that have always been most attractive to human settlement and use – lands along rivers and small drainages, resource-rich wetlands and backwater sloughs, upland moraines and prairies, and former Lake Michigan beach ridges. Secondly, most of the archaeological sites located outside of protected Forest Preserves property have been destroyed by over 150 years of urban development. So, it is no exaggeration to say that our best and often only, opportunity to learn about the early residents of northeastern Illinois lie on lands preserved and managed by the Forest Preserves.

What are some of the interesting sites ISAS has recorded recently?

We have found new groups or complexes of sites situated along various stretches of the Des Plaines River, in a number of different Preserves, that tell us people were intensively using this river environment in the past, especially during the Late Woodland period (A.D. 300-1100). Broken pieces of ceramic vessels and the types of stone tools found, tell us that people were living here in small camps on a semi-permanent or seasonal basis. The earthen mounds also found here, which may or may not contain burials, suggest that this river and landscape was important to people in the past for reasons beyond just the area’s ability to provide food and transportation.

We have also relocated and analyzed large artifact collections originally found during excavations that occurred in the 1960s and 1970s on Forest Preserve property. One site in particular, located in McMahon Woods, is a large village dating to the early 1600s. This very important and unique site contains information about the initial interactions of Europeans and Native Americans in the Chicago area. For more information, download the ISAS 2015 Annual Report (PDF)

What do archaeological sites tell us about changing landscapes and environments through time?

Plant and animal remains found at archaeological sites – including things eaten, things used to make tools or clothing, and even things used for decorative or religious purposes – tell us what sorts of species and species communities were living in the rivers, wetlands, prairies and forests of Cook County hundreds and thousands of years ago. Also, where we find sites, where on the landscape people were living, helps us understand how inland river systems and Lake Michigan water levels shifted through time.

How has the landscape changed through time?

This is a long and interesting story, and these changes are the result of both natural and human-directed processes. The short answer is that the landscape has changed significantly over the last 12,000 years. For example, during the Paleoindian period, the Lake Michigan shoreline was located as much as 15 miles west of its present location, with water covering many of the low-lying areas in Cook County. However, around 8,000 years ago, the Lake Michigan shoreline was much lower than today meaning that any human settlements once located along the beaches at that time are now underwater. Changes in temperature and rainfall levels bring changes in habitats, and changes in resources and transportation corridors available for humans to use and exploit. By about 200 B.C. people began cultivating native seed crops and by at least 800 A.D. some groups were engaged in more intensive corn agriculture. People continued to selectively choose particular wild plants, small and large mammals, and various aquatic species over other less desirable species. All of these human activities and choices have environmental consequences. Of course, in our more recent history, we have altered the course of the Chicago River, drained marshes, increased flooding and erosion along rivers, introduced non-native plant and animal species, and so forth. What we consider to be the natural landscape, and what we consider to be the human or cultural landscape, are not entirely separate things. Our present world is a reflection of a very long interrelationship between nature and humans.

What happens to the artifact found in the Forest Preserves?

Artifacts recovered from the Forest Preserves are first taken to the Illinois State Archaeological Survey’s Northern Illinois Field Station in Elgin for cleaning, documentation, and analysis. Then, because these materials come from sites on publicly held lands in Illinois (these are publicly held resources), the artifacts and all documentation are transferred to the Illinois State Museum in Springfield for professional curation. Artifacts are available to be transferred back to the Forest Preserves, on long-term loan, for display in Nature Centers, in other facilities or for events.