Digging Into Wisconsin’s Sandy Past with Historian Jean Mansavage

You're listening to Perspective on WFHR 1320 AM, 97.5 FM.

I'm Melissa Kaye, bringing you news in our community.

During this interview, I'm talking with Jean Mansavage, retired federal historian from the Department of Defense Agencies in Washington, D.C., active local historian, and Wisconsin master naturalist.

Thank you for joining me, Jean, to share with the community some of our own local natural history in the Sand Counties area.

Well, Melissa, thank you so much for having me.

It's wonderful.

I moved back home, and now I can share more of the stories with people who live here.

Yeah, because you grew up in this area.

Laft had your career.

How many years were you serving with the Federal Department of Defense?

I was with the Department of Defense for about 30 years, with four different agencies.

And what brought you back to this area?

It's been my plan, my whole career, to move back here, to retire back here.

It's because this is where my heart is, and it's where...

It's home.

Perfect.

Beautifully said.

Well, let's dive into what we plan to talk about today for those who don't yet know of Aldo Leopold.

Gene, you're going to introduce us to him today, and I hope we can do more interviews about him.

Leopold worked for the U.S.

Forestry Service, among other conservation efforts, and wrote a book called A San County Almanac.

In the book's forward, he mentions how conservation is getting nowhere, because we regard land as a commodity that belongs to us.

Instead of a

community to which we belong.

Now the indigenous people who lived in this area for generations before Europeans showed up approached land in a much different way.

Could you start there for us?

Yes,

in fact, thank you for bringing this up.

And before we begin, I would like to acknowledge the indigenous peoples who have called Wisconsin's land and waters home for generations.

Of the 12 original First Peoples of Wisconsin, the Ho-Chunk and the Menominee nations have historical and spiritual connections to the land where we reside now.

And each of us, I think, have an obligation.

to learn about an appreciation, the history of the land we are on, as well as the past, present, and future contributions of Indigenous people who have been and continue to be its caretakers.

Beautifully said.

Now, the Sand County Almanac, when Leopold says that, what does he mean by sand county?

Good question.

there

is no sand county

in the state.

I knew there were 72 counties and

I

didn't think sand was one of them.

So recently within the last couple of decades the DNR has actually named all of the ecological landscapes in the state and ours is the called the Central Sand Plains Ecological Landscape that formed around what was once Glacial Lake Wisconsin.

Okay, Glacial Lake Wisconsin.

Overall, this ecological landscape is, as we all know, relatively level, sandy.

And it's comprised of forests, wetlands, and barrens.

It's one of 16 equal regions in the state.

And it covers roughly 3,400 square miles, or about 6% of the

land in the state.

So that's a pretty big area here, kind of in the heart of Wisconsin.

But this was formed throughout ancient history.

Yes.

And there were some things that I've learned by doing some research that have just blown my mind.

And in order for us to just understand why we've got all this sand, we really have to go way back in geological time to understand why.

And we're talking like 500 million years way back, right?

Yeah.

And back then, it was known as the Cambrian period.

Wisconsin, what's now Wisconsin, was actually located south of the equator before all those land masses broke apart into what we have today.

And it was just off the coast of a slab that was called Laurentia.

And back then, the land that would become Wisconsin was covered by a shallow tropical inland sea that deposited thick layers of sand and mud on the ocean floor.

And then, about 440 million years ago, there were all sorts of small aquatic animals and plants that were deposited when they die on the ocean floor.

And over time, all these little creatures, plus the sand and the mud, were buried and compressed into what they call late Cambrian sandstone, which is the geology that underlies the central sand plains.

And for any of us who were kids that would would find pieces of sandstone or or climb in the bluffs around in this area, because I grew up over by Tomas Barda, we go to Oakdale and climb up on the sandcliffs and you could just break chunks of it off.

And Monroe County is part of the Central Sand Plains.

So that's that's exactly why.

And so there's more geological history too.

So getting a little closer to today, about a million years ago,

What we all know is kind of as the ice age.

There were glaciers that covered the state, all but what we call the Driflus area, which is the southwestern corner of our state, and approximately 100,000 years ago.

So now we're getting close.

We're getting real close

now.

The climate cooled again, and a massive glacier spread across the...

the continent during what they actually call the Wisconsin Glaciation episode.

And near the end of this cycle, about 32,000 years ago, the glacier began its final advance into Wisconsin.

And so now this leads us into Glacier Lake, Wisconsin.

Yes.

Yes.

About 18,000 years ago, the Glacier Lake, Wisconsin, which is not what we think of as Lake Wisconsin today, but the Glacier Lake, which was

in total 1825 square miles.

So that's about the size of Rhode Island or what they put within Grand Canyon National Park was

about the same

size.

So this lake was 18 over 1800 square miles and it was 70 miles long and it reached the depth of 160 feet and the Statue of Liberty is about 160 feet.

So it

was pretty deep.

Yes.

So it formed when

the outlet to what was then the Wisconsin River got blocked by ice that had been stopped by harder underlying bedrock that was down near Baraboo.

So it's quartzite down there, not sandstone.

So when the ice came upon it, it stopped the glacier from proceeding.

And so you had the lake, you had the water melting off the glaciers, but you had the river backing up that created Glacial Lake Wisconsin.

And then about

14,000 years ago, the climate warmed again.

And the ice dam that was holding everything back was breached.

And the lake drained rapidly.

It was catastrophic flooding.

It dropped water levels by about over 100 feet in just a few days.

And

this kind of catastrophic flooding is what created the Wisconsin Dells.

And it left behind all the accretions that make up our modern day sandy soils.

And then that sandy soil has been a part of the history of this area for all of our living history.

They say that soil is destiny.

And it truly is.

If you look at our agriculture and our recreation, those things that happen as a result of

all those millions of years ago, help us be the people that we are today.

They say that with wine, there's a concept called terroir.

So all these wines are special because of the grapes that they're made of that were

grown

in special regions under certain temperatures and precipitation.

Well, we're people.

And I think that there's a certain terroir of the soils on which we've grown up that make us the people that we are.

I like to watch archaeological shows, and I know that there are scientists who taste soil.

They truly do.

When they're digging just to see what it's made of.

And don't call it dirt.

Them spiting words.

Yes.

Well, let's take a quick break here.

Let's hear from our sponsors.

I'm Melissa Kay, and I am talking with Gene Mansavage.

I appreciate having you here today, and you're listening to Perspective on 1320 AM, 97.5 FM WFHR.

You're listening to Perspective on WFHR 1320 a.m.

97 5 fm.

I'm Melissa K and I'm talking with Jean Mansavage She is a retired federal historian from the Department of Defense agencies in DC and active local historian in Wisconsin master naturalist We've been talking about the ancient history of this area and where we left off was talking about the soil content and how important that is and vital to the way that we live on this earth today so or on this on this area of

of land.

So tell us more about the soil.

Sure.

So the materials that we talked about earlier, the soil materials, were largely, what we've got left, were largely a result of wave action that took place within this huge glacial lake.

So you've got waves sloshing around on all those sandstone.

And we all know when you rub sandstone in your hands, how easily it erodes.

So

all that material kind of sifted to the bottom of the lake.

and created some of the soil.

Also, there was glacial meltwater and outwash that came from little, little tiny rivers underneath the glacier, whereas it melted and brought more sand, gravel that we all know about, as well as clay and silt that all settled kind of at the bottom of this lake.

And in addition to the obvious sandy landscape that we all know about, we're also...

familiar with the cranberry bogs that are out toward Babcock to the west.

And we actually have the second largest percentage of wetlands of all the 16 ecological landscapes in this state.

We've got about 26% of our areas covered with wetlands.

This acreage, it's not just the sand that came from Glacier Lake, Wisconsin, but we have an area that was once called the Great Swamp of Central Wisconsin.

And it formed in the lower lying areas that were on the margins of this old Glacier Lake.

So in these areas, the silt and clay from the Glacier Lake bed combined with really

relatively high water tables on those margins and it impeded the drainage and created really poorly drained kinds of peatlands.

So in these peatlands that we all know about out near Babcock, early in the 20th century, believe it or not, many people aren't aware, but we tried to drain them thinking that this dark peat type material was really soil rich.

agricultural property.

Would have been good for planting other crops in.

But people didn't know about the actual makeup of that soil and the water table again being very high and in the soil fertility was very very low.

In addition there are growing season frosts that occur out in those lowlands and it makes agriculture largely unsuccessful except of course for commercial cranberry production.

Because cranberries were growing there naturally.

Exactly, exactly.

Well, now let's move into something that you and I have talked about outside of this, but the tension zone.

Can you explain what that means?

This is another cool thing that I never understood growing up here.

I had observed it, but I didn't know there was a real reason for it.

So what the heck is the tension zone?

there are factors of temperature and precipitation that really divide Wisconsin into a northern and a southern climatic zone.

However, our region lies in this area that's called the tension zone, and it's tension between those northern and southern types of climates.

So the region... Whether, not personalities.

Whether, excuse

me.

The tension zone is a region where northern, cool, dry arctic air from Canada, which causes more snow and colder temperatures, collides with the southern air that's controlled by the winds from the Pacific Ocean that combines with tropical air from the Gulf of Mexico, which creates warmer winters and less snow.

And the tension zone is not only climatic, but the climate determines

the different types of trees and understory that we have in our forests.

And

there is an S shape that really runs sort of from Eau Claire down to Milwaukee.

that delineates where these two temperatures, the northern and the southern climates, are hitting each other.

So this tension zone is not just climatic, but it delineates the northern mixed hardwood and pine forests and the southern oak savannas and prairies that we have in the state.

And in this tension zone, if you look around in the woods around here, you'll notice that there are both the northern and the southern ecosystems that are interspersed.

So we've got the pine trees with all those beautiful maples and

and oaks, and it's mixed.

And that's a result of having both of these climates playing up and down in our area.

And the way that they mapped this...

is also fascinating because they took, I'm sure, a while to figure out exactly where the line went.

Exactly.

And we really didn't know about this until the 1950s when the individuals who study all this, the forests and things like that, they actually mapped out, they did plots where they figured out how many trees per acre or per square foot were on certain

plots of land.

So John Curtis, who's the individual who came up with this idea of the tension zone, looked at over time the different precipitation amounts and the temperatures and kind of plotted where those lines lie in the state.

And then he looked at the different kinds of trees, did very scientific surveys of what trees were located where, and was able to determine

that the fluctuations in temperature and precipitation match the fluctuations in the types of trees.

And so

many, many plots comes up with one final drawing.

And our area is actually right here in central Wisconsin.

We've got probably the broadest area of this tension zone.

It can go anywhere from

eight or 10 miles to 30 or 35 miles.

And we're in one of those areas where it is pretty wide tension zone.

Interesting.

So if you grew up in this area and you go up north, you're going to see trees in the north that you see here and in the south.

If you head to the south, you're going to see trees that are here.

That's really interesting.

We had a cottage in Monacoa or near Monacoa, and it was always all those big pines and poplars, but an aspen.

We didn't have that all at here.

And then you'd go south just into Adams County.

And you've got all the burroke and the jack pine.

But why is it different in that, you know, where we

are here?

And again, I grew up on 20 acres of woods, and I always knew that our woods were unique.

And it's actually my preference and my bias preference.

But now I know why.

Because we're

in the tension zone.

Tension zone.

Yeah.

I just think it's

fading.

Well in our last couple minutes here, why don't we take a brief dive into Alda Leopold?

Gene if you could just give us a little brief overview of his book the Sand County Almanac We're gonna do this in another segment because we there's so much more here, but what can you tell us just briefly?

So one thing I wish people would

would do who live in this area is get a copy of a San County Almanac.

You can get it on Amazon for like seven bucks.

I never read this book until I was a senior in college in Texas when I took an environmental history class.

And if I had read this back when I was a kid, I would have appreciated where we live so much more.

So Leopold talks about his book encompasses this area that is the central sand plains ecosystem.

And he wanted to write a book to give his readers a deeper understanding and appreciation of nature in general.

And he believed that when a person or a nation values the land for both economic and aesthetic reasons, then they'll protect it.

And the almanac is kind of stuck structured into three different parts.

The first section is 12 different essays, one for each month of the year, that detail seasonal changes on his sand farm that's located down on the Wisconsin River near Baraboo.

And the second portion contains essays that describe different North American landscapes, where he looks at the effects of human development, noting that many of the things that we've done have degraded the ecosystems and have led to loss of wildlife.

Again, he's writing this back in the 30s and 40s, so before some of the conservation ideas have taken shape and we've saved some of our land.

use better conservation practices.

And the final section includes Leopold's most influential essay.

It's called The Land Ethic.

And in that, he argues that we humans must extend our moral considerations to the land.

And as you mentioned earlier, viewing it as a community to which we belong, rather than simply a resource to be exploited.

People don't know this, but it's the book has sold more than two million copies has been translated into 14 languages and has influenced the environmental movement by providing scientific Ecological and an ethical framework for conservation

Wow Well, we're gonna have to stop here, but we're gonna have you back again Jean to talk more about this because I think that the natural history

is something that a lot of people don't know and recognize as much as we could and should and appreciate it.

So, thank you for coming back.

Will you come back again?

Absolutely.

Wonderful.

I'm Melissa Kay, speaking with active local historian and Wisconsin master naturalist, former historian from the Department of Defense Agencies in Washington, D.C.

Gene Mansavage.

Thank you for talking with me today, Gene.

Thank you for having me.

And thank you to listeners joining us for news in our community on Perspective, 1320 AM, 975 FM, WFHR.