Our Ice Age Connection
Educational Opportunities at New Fox Science Preserve
A former gravel pit in Scio Township is getting new life as a nature preserve! Home to glacial boulders and prehistoric vegetation, the 49-acre Fox Science Preserve is the newest addition to the system of preserves protected by the Washtenaw County Natural Areas Preservation Program. Purchase of this site was a collaborative effort involving the former owners Mel and Betty Fox, the City of Ann Arbor Greenbelt Program, the Scio Township Land Preservation Commission, and the Washtenaw County Parks and Recreation Commission, which now owns and manages the land.
Tremendously exciting educational opportunities exist in the bottom of the pit. With so many biological and geological events crammed into one small space, teachers can easily watch from afar while their students explore the natural history of the region. In fact, former owners Mel and Betty Fox have been allowing students to access this property for more than 35 years; over 40,000 students have used the site as an outdoor classroom! Scattered around the bottom of the pit are table-sized glacial boulders of granite, tillite, gneiss, and limestone. Some of these have come from north of Lake Ontario, glacially transported to their present location. Glacial scratches on boulders allow students to see evidence of moving glaciers and to imagine what it would be like for a mile of ice to sit above where they are standing. Fossils can be found in the limestones, and countless small samples of every sort of rock have been collected by young students over
the years.
Glaciation is a fascinating process that dramatically changed the landscape of the Great Lakes Basin. A short while ago in geological time¡Xa mere 15 millennia or so¡Xmost of southern Michigan was covered by a vast ice-sheet stretching northward into Canada. Initially, this Wisconsin Glacier scraped and gouged the surface of the land, expanding and moving southward when the climate was much colder than today. Later, when the climate warmed, the glacier retreated leaving behind mounds, rocks, and boulders, and depressions that filled with melted ice forming lakes and ponds. The Fox Science Preserve includes the remains of a gravel pit, dug to contribute material to the construction of Interstate 94. Excavation was necessary to reach and extract the sand and gravel deposited there by the glacier thousands of years ago.
Although glacial geology is the primary focus of educational forays at the Fox Science Preserve, the site is valuable for studying plant communities as well. Perhaps the most unique feature of the pit is the presence of a well-developed cryptogamic crust¡Xareas of ground that appear to be bare but are in fact covered with algae, fungi, tiny mosses and the precursors of lichens. Primary plant succession begins when these tiny plants develop on bare rock or sterile sand where no previous plants or soils exist. Only recently understood, this living crust is of vital importance in stabilizing soil and providing nutrients so that higher plants can get a foothold. Untouched for almost forty years, the gravel here resembles that which must have occurred upon retreat of the glaciers 12,000 years ago. In fact, the pit bottom represents one of the best examples of primary plant succession in our area! In other areas of the pit where succession is more advanced, mosses, prairie grasses, goldenrods, asters, and shingle oaks are present on the developing soils. In the simplest terms, succession is defined as the (somewhat) predictable change from one plant community (a group of plants that grows together) to another over time. Climate, latitude, elevation, soils and hydrology all play a role. Thus we see shrubland replacing grasses and perennials, which in turn is replaced by pioneering trees, which are followed by more shade-tolerant trees.
Being able to see so many primary plant species, glacially transported boulders, and a well-developed cryptogamic crust is truly unique for this area. This Natural Areas Preservation Program preserve offers a special opportunity for students of all ages. We now have a glimpse of what the land surface looked like after the glacier retreated, a window into the past, one might say.
The Fox Science Preserve will likely be open to the general public later this year. Plans for construction of the preserve entrance and parking are in the works, stay tuned for more information.
