| 75 million years ago |
Shallow seas cover the Chicago area. The climate is warm and
humid - dinosaurs inhabit the land, sea and sky. |
| 65 million |
Newly exposed land surfaces are changed by wind and rain.
Flooding waters cause erosion and sediment deposits and create riverbeds. |
| 6 million |
The climate becomes warmer and drier and grasses cover the
land. Deep root systems evolve to survive fire and drought. |
| 1.5 million |
First mammoths arrive and large mammals become plentiful. |
| 18 thousand |
Pleistocene glaciers cover most of Illinois with massive sheets
of ice up to a mile high. The climate is as cold as the Arctic. |
| 15 thousand |
The ice sheets slowly retreat northward and meltwater creates
a great lake larger than today's Lake Michigan known by geologists as Lake Chicago.
Glacial erratics from Canadian bedrock are left behind. The climate warms and tundra
replaces the glaciers with coniferous (pine) forests. |
| 12 thousand |
The climate continues to warm. Oak and hickory trees replace the
pines. Grasses and wildflowers move northward from the south and west to become
the Illinois prairie. Large grazing animals like buffalo, elk and deer replace Ice Age
mammals. |
| 8 thousand |
The first Native American people follow the herds northward. Fire
becomes a new force on the landscape. |
| 1674-80 AD |
French explorers Jacques Marquette and Louis Jolliet arrive
and trade with native tribes. La Salle calls region "Che-cau-gou"- native term from
which Chicago gets its name. |
| Late 1770s |
Jean Baptiste Point DuSable establishes first settlement
on the grasslands by Lake Michigan which becomes present day Chicago.
|
| 1830s |
Native Americans are forced westward from the Chicago area.
European settlers begin arriving. John Deere invents steel moldboard plow which
breaks tough prairie sod and begins farming practices which destroy the prairie. |
| 1852 |
Black bear, bison, cougar and lynx still live in Cook County wilderness.
German community of Franzosenbusch is founded near Wolf Road Prairie. Scattered
communities of German settlers establish underground railroad stations to aid slaves. |
| 1925 |
The Village of Westchester is founded. |
| 1970 to present |
Wolf Road Prairie is officially recognized and volunteers
work to preserve the prairie. Land in the prairie is purchased by Save the Prairie
Society, Illinois Department of Natural Resources, and the Forest Preserve District
of Cook County. Wolf Road Prairie becomes a dedicated Illinois Nature Preserve.
|
