Ivanhoe is a remnant of a globally unique natural community known as "dune and swale." It was formed when ancient glacial Lake Chicago receded thousands of years ago. A series of linear sandy beach ridges alternate with long narrow wetlands in parallel bands to form this rare community. Like counting the rings on a tree, aerial photographs from the early 1930s clearly show this distinctive topography extending inland several miles from the shores of Lake Michigan. Rapid industrial and residential development of the lakeshore destroyed all but tiny fragments of this incomparable landscape.
The Nature Conservancy
Located in a working class neighborhood of Gary, the east 40 acres of Ivanhoe had originally been plotted into individual lots for residential development. The Conservancy began acquiring these lots in the mid-1980's through tax auctions and donations. The west unit of Ivanhoe - 80 acres - was amassed in 1991.
With the help of volunteers, interns, and partner organizations, plus financial assistance through various public grants, the Conservancy transformed Ivanhoe into a rich patchwork of upland savanna, prairie, forest, and wetland by thinning out the overstory through prescribed burns and manual labor.
In the summer of 2001, the first of 250 Karner blue butterflies were released at Ivanhoe as part of a multi-year effort to restore this federally endangered species to the preserve. The reintroduction projects are ongoing and will be so until viable populations are seen. The success of these projects have the Conservancy working with federal and state officials to expand its efforts to restore Karner blues to other preserves in northwestern Indiana which include areas guarded by the Southern Lake Michigan Rim Project Office.
Dune and swale complexes are a series of roughly parallel, sandy ridges and low, wet tracts of land. In Indiana, they are formed partly from the irregular cycles of high and low water levels of Lake Michigan. Past glacier movement, wind (eolian processes) and weather play an integral part of the formation of the dunes and swales as well.
There are four distinct zones within a dune and swale complex. They are: the beach and foredunes, open interdunal swales, forested dune ridges and the forested swales. Each zone is characterized by the vegetation (or lack thereof) found and the amount of sand accumulation. A diverse mosaic of black oak savanna, prairie and wetlands is commonly found within a dune and swale community.
The size of the complexes can be quite expansive. In fact, the dunes along the Great Lakes are some of the largest systems of freshwater sand dunes in the world, ranging from high, forested dunes and linear dune ridges commonly backing sand beaches.
The preserve is open for visitation, and includes an interpretive trail. For more information please consult the Conservancy’s Preserves Visitation Guidelines.
From the I-80/94 and I-65 interchange, travel west on I-80/94 approximately 7 miles to the Cline Avenue North exit (S.R. 912. Travel north roughly 2 miles to U.S. 20 E (W. 5th Avenue). Continue traveling east on U.S. 20 E. about one mile to Hobart St., and turn left (north). Drive north until Hobart St. ends, move the barrier, drive in, park, and move the barrier back. You may want to place a sign on your front dashboard indicating that you are there to visit the preserve.