Not long ago, as the geologist measures time, the water released from a melting glacier during the last great Ice Age created a much larger Lake Michigan, called Lake Chicago, which covered most Cook County. This water stood 40 feet deep over what is now the Sand Ridge Nature Center. As the water found its way to the ocean, the level of the lake dropped, rose, and dropped again, forming beaches and low sand dunes on many temporary shorelines. Eventually, prairies and woodlands grew on the sandy soil of the long ridges left behind as the lake receded. The lower areas, between the ridges, developed into large wetland communities. Today, the Nature Center building stands on a 6000-year-old broad, low ridge of sand and water polished pebbles, surrounded by a rich mosaic of woodlands, prairies and wetlands.The ecosystems of Sand Ridge Nature Center include several small sand prairies. These rare communities feature native grasses such as little bluestem, prairie dropseed, and Indian grass. Wildflowers are very diverse, and include hoary puccooon, shooting star, prickly pear cactus, and other flowers of sandy or acid soils. Summertime is a busy time on the prairie, with millions of small creatures, from birds to garter snakes to shrews, bees, butterflies, beetles, ants and spiders, all intent on finding food, finding mates and rearing their young.
The woodlands of Sand Ridge are dominated by several species of oak trees, including black oak, white oak, pin oak and bur oak. These open-crowned trees allow sunlight to penetrate to the woodland floor, where a huge variety of spring and summer wildflowers, sedges, and ferns flourish. Other interesting and unusual trees within the preserve include blackgum, sassafras, quaking aspen and bald cypress. Many animals of the woodland are secretive, and are only seen by those who are quiet and observant. These animals include white-tailed deer, coyotes, owls and flying squirrels.
There are several different types of wetlands within the preserve. A large pond attracts geese, ducks, kingfishers, herons, frogs and turtles. Several much smaller vernal ponds, that are present in the springtime, but generally dry up by mid-summer, are nurseries for chorus frogs, American toads, salamanders, and a host of smaller creatures. Marshes, some of which are nearly dry by late summer, are pristine places used by wildlife year-round as nurseries, resting-places and diners. Some of the wetland plants that can be seen are cattails, cord grass, tussock sedge, buttonbush, rose mallow, water lily and cardinal flower.
People have been living in this region for thousands of years, following the retreat of the glaciers. It is likely that the first people lived in small groups, following game and gathering what they needed from the land. About 2,000 years ago most people started living in settled communities based upon a combination of agriculture and hunting. Native American populations were small, with only a few thousand people living in the Chicago region. Their way of life followed the seasons, with spring and summer spent tending crops of corns, beans and squash by villages. After harvest, family groups moved out to winter hunting camps. Some common game animals were bison, white-tailed deer, and wild turkeys. Trade routes up and down the rivers and overland along high ground brought copper, flint, shells, and seeds to the various villages.
Even though the population of native people was small, they had a large effect on the regional landscape because they regularly set fire to prairies and woodlands. Burning kept these ecosystems open and park-like for ease of travel, enhanced the diversity of plant and animal life, and attracted game to the rich new growth.
With the arrival of Europeans in North America, many of the native people were ravaged by new diseases, and displaced by the new colonists pushing ever westward. Tribes moved west, and came into conflict with the people already there. Their way of life also changed with the importation of desirable European trade goods such as iron pots and steel axes. The men turned more of their time to trapping and hunting beaver and other furbearers for trade.
The first Europeans in the area were French fur traders during the seventeenth century. They developed close ties with the native people, and intermarriage was common. Father Marquette and Louis Jolliet visited the area in 1673 and established peaceful relations with the native people. In 1779, the first permanent trading post in the region was established by Jean Baptiste Point du Sable at the mouth of the Chicago River.
After the War of 1812, the United States gained control of the lands of the Chicago region. Settlers poured in, and surveyors marked off the land so it could be sold. The native people lost their rights to the land through a series of treaties and conflicts, and many moved west across the Mississippi River.
Chicago grew quickly because of its favorable position on Lake Michigan and major rivers, making it a center for trade and manufacturing for much of North America. By 1870, 350,000 people lived in Cook County, and more than a million people lived in Chicago by 1900. Farmers of the Calumet region, where Sand Ridge is located, often made their living on small truck farms, growing fruit, vegetables and meat to supply the growing city to the north and the market towns of the region.
With new building techniques and need for steel mills and refineries, the formerly undesirable sandy dunes and wetlands of the Calumet region came to be used extensively for industry. Population increased dramatically as workers built homes near their place of work. Farming became less of a livelihood as the towns turned to manufacturing and service as their resource base.
During the early years of the twentieth century, many far-thinking people became concerned with effects of increasing urbanization and lack of contact with nature. They saw that many ecosystems and beautiful natural areas were being lost. In the Chicago region, after much time, effort, and politics, the Forest Preserve District of Cook County and DuPage County were established in 1915 to preserve the native flora and fauna of the region for the education, pleasure, and recreation of the public. Land purchased included areas that were naturally beautiful or contained rare and unusual ecosystems, as well as old farm sites.
The preserve of Sand Ridge Nature Center is on former farmland in an unincorporated area of the town of South Holland. Because of the sandy soil and large wetlands, much of the land is marginal for farming, and it appears that much of the property was not heavily used. The original Nature Center building was built in 1962 and immediately became an educational destination for school groups and individuals. In 1992, the present Nature Center building was reconstructed to be handicap accessible and to better serve the changing needs of the public, with more exhibit space and a large classroom.
* Much of the information for this section came from “Chicago Wilderness, An Atlas of Biodiversity”, written by Jerry Sullivan, published by Chicago Wilderness.