The Driftless is famous, in an underplayed, Midwestern sort of way. I suspect that only people in the region and geology students ponder it much. It gets some play among fly fishers because of its trout streams, though even then its not first on the list of places to fish. There’s a popular Orvis fly fishing podcast by Tom Rosenbauer, and when from time to time the Driftless gets mentioned, he always says that he really wants to get there soon. Apparently soon time like glacial time is pretty long.
The Driftless is usually referred to as the Wisconsin Driftless, but it’s actually located in parts of Illinois, Iowa, Minnesota, and Wisconsin, right where the four states dysfunctionally try to join their borders at the Mississippi River. They don’t quite make a Four Corners, and Illinois is usually ignored anyway. Its portion of the Driftless is small, and it has no trout streams. I’m sure that otherwise it’s the very thing.
Driftless is a great name. There’s an upended, unanchored feel to it, like Clint Eastwood as the Man with No Name. In truth though, it’s not glamorous like the Rockies or the West Coast. It’s not the historical epicenter of fly fishing like Pennsylvania or the Catskills. It’s in Wisconsin. It doesn’t wear a poncho or smoke a cigar. It’s in Iowa. Is it heaven? No, it’s Iowa.
Glacial drift is the geologic term of art for all the silt, sand, rocks, and boulders that glaciers put in their pockets when they went for a stroll, and then left behind when they turned for home. The Driftless is just that–it’s without the silt, sand, rocks, and boulders that a glacier deposits.
The Last Glacial Age lasted about 100,000 years, and ended at 2:30 in the afternoon on a sunny day 14,000 years ago. During the Last Glacial Period, all of Canada was covered with ice, which explains hockey, but parts of Alaska–presumably including the Bering Strait land bridge, Beringia–weren’t, which explains America’s first immigrants (who, I’m reasonably certain, weren’t documented). Sea level at glacial maximum–like drift that’s a term of art–was as much as 400 feet lower than now, and as sea level rises that’s getting lower all the time. Much of the Northern United States was covered with ice, but the Driftless wasn’t. I don’t know why, it just wasn’t. There was ice to its right, to its left, above it and below it, but it remained–Driftless.
All those thousands of feet of ice did at least three things. The glaciers scoured and flattened things out, and they filled in what was left–that’s where the deposited drift went. They also forced water to go in new directions. By missing the Last Glacial Period, the Driftless’s pre-glacial geology was left pretty much alone. It was left with shallow soils–Look ma! No drift!–covering various kinds of rocks: sandstones and limestones and dolomites and whatnots. They’re the kind of rocks that allow a karst topography.
What is a karst topography? Think of it as fractures, pockets, underground streams, and caves in soluble rock, and, in the case of the Driftless, streambeds on the surface carved a bit deeper by the runoff of glaciers and the release of prehistoric great lakes when ice dams fractured. The results produces springs and spring-fed streams. The water gets cold down under, and the trout get cold water up top. In the Driftless, on the surface, there’s a lot of trout habitat. It’s not big, western rivers. It’s small streams through farmland, and no one is ever very far from cheese curds.
The original trout in the Driftless were brook trout, but brown trout and rainbow trout were introduced. All three can be found there now, plus the sterile hybrids of browns and brookies, tiger trout. It is the kind of fishing freshwater fly fishers crave, and since I first read about wild trout in northeast Iowa, I’ve been a wee bit obsessed with going to the Driftless.
I’ve actually been to all of these states before. I’ve been to Minnesota in winter, which is a treat, and a couple of years ago we fished in Wisconsin for Muskie, so no one should be surprised that we didn’t catch anything and now have to go back. I only passed through Iowa a long, long time ago, but it was green and rolling, and I was from a flat brown place and I thought it was beautiful. We stopped in the Amana Colonies just north of Iowa City, and it did look a bit like heaven. It was Iowa.
