Planning the adventure, following the glaciers
I am once again relying on the Indiana Geological Survey (IGS) for perspective in my Northern Indiana guidebook, reusing a quote in the Southern Indiana version: “No other event since the extinction of the dinosaurs sixty-five million years ago can compare to the Ice Age in terms of the profound effect it had on our landscape and the natural environment in which we live today.”
That quote assumed more relevance this week as I began mapping the year’s guidebook travels. Exploring what scant little there is left of the Northern Indiana landscape encountered by French voyagers in 1670s is indeed experiencing the remnant effects of the “rivers of ice,” to cite the IGS again, which have repeatedly advanced and retreated over the Northern Indiana landscape the past 700,000 years.
When I photograph the Cedar Creek in the Dustin Nature Preserve in Huntertown, for example, that Natural, Scenic, and Recreational River's water will be following a course that was set some 13,000 years ago, when the last retreating Wisconsin Glacial ice sheets left behind a ridge of glacial debris known as the Fort Wayne Moraine.
The Wisconsin Glacial, the latest of the two Ice Age events that covered Indiana in the last quarter million years, began about 50,000 years ago and was gone 10,000 years ago. It ground and scoured the entire state north of a ragged line from Terre Haute to Richmond.
Two glacial lobes alternately advanced and retreated over the area, leaving behind the Glacial Lake Chicago, which covered Northwest Indiana and eventually receded into Lake Michigan, and the Glacial Lake Maumee, which reached Fort Wayne and eventually shrank to Lake Erie.
When shooting Summit Lake State Park in November, I stood just a few miles from Indiana’s highest elevation – 1,257 feet – in Wayne County where the landscape is gently rolling ag. Beneath my feet were a couple hundred feet of Wisconsin Glacial deposits called till, unsorted mixtures of soil, gravel and rock, that sit atop the highest bedrock in the state and gently slope north, west and south. When the French arrived, Northern Indiana supported more than 11 million acres of beech-maple forest and a little less than a million more beech-maple with oak and hickory mixed in.
As I did with the Southern Indiana guidebook, I’m organizing this one around the North’s six natural regions – Lake Michigan, Northwestern Morainal, Grand Prairie, Northern Lakes, Central Till Plain and Black Swamp – which were identified by the Indiana Academy of Science in 1985. Each has a unique assemblage of natural features that include, along with glacial history, climate, soil, bedrock, flora and fauna.
Within those regions I’ve identified nearly 200 natural areas with some level of protection. Since I will be sleeping on the ground on the long-distance journeys, I’m mapping the excursions around state parks, specifically Dunes, Tippecanoe River, Potato Creek, Chain O’ Lakes, Pokagon, Prophetstown, Oubache and Mounds.
Among the nature preserves, parks, and wildlife areas on the itinerary is the state’s only national park: the Indiana Dunes National Lakeshore. So ecologically spectacular is this refuge’s 15,000 aces, its Cowles Bog is known as the “birthplace of ecology.” Pinhook Bog and Cowles – named after University of Chicago Professor Henry Cowles, a pioneer in the field – are National Natural Landmarks. So are the Big Walnut Creek and Shrader-Weaver Nature Preserve.
The Fawn River Nature Preserve in LaGrange County is bisected by the Fawn River, which is reputed to be the state’s wildest waterway.
But while there are a surprisingly large number of natural areas north of I-70, they are small. After two centuries of ditching and draining, there’s virtually nothing left of the Grand Prairie Natural Region, which stretches a hundred miles or so due south of the Valparaiso Moraine and Lake Michigan.
I've seen in many forms what humans have done to the Wisconsin Glacier's natural legacy. I've stood inside a South Bend combined sewer overflow and stood atop a pile of waste tires 75 feet deep. I grew up in Indianapolis.
I’m ready to see what's left of it.
Photographs: Top, Turkey Run State Park; Center Top, Fort Harrison State Park; Center Bottom, Fall Creek Gorge Nature Preserve; Bottom, Raccoon State Recreation Area.