Pat Hashman of Story City examines a find during an archaeological dig Sept. 15 at Whiterock Conservancy.
Pat Hashman of Story City examines a find during an archaeological dig Sept. 15 at Whiterock Conservancy.

September 23, 2018

When we arrived at Whiterock Conservancy Sept. 15 for a hot day of archaeological digging, it was difficult for us to leave our air-conditioned car.

We aren’t archaeologists, so we weren’t sure what to expect. Dinosaur bones?

The man in charge of the dig, Joe Artz, is a specialist in geoarchaeology, which involves studying features in the earth’s surface and relating archaeology to the landscape to help determine how items were buried and how long they’ve been there.

“I look more for dirt than artifacts,” Artz said — in fact, his coworkers call him “the dirt man.”

After meeting the other dozen or so volunteers, we climbed into the bed of a truck — only to find it wouldn’t be taking us all the way.

We hiked to the dig site, a five-minute foray through thick grass and plants that were sometimes taller than us, with no path in sight.

Finally, we made our way out of the grass maze and stood on a ridge above the Middle Raccoon River.

Up until then, we’d had no clue that where were standing, only half an hour away from our homes in Carroll, was once a glacier.

The glacier, which formed the Des Moines Lobe, entered Iowa about 15,000 years ago. One mile high, it moved one-eighth of a mile a year.

“It got to Des Moines and Terry Branstad said, ‘OK, that’s far enough,’” Artz joked.

It eventually advanced to what would later become Ames and then Coon Rapids.

About 3,000 years after the glacier first entered Iowa, it had melted.

“Everything that we are standing on has been built up in past glacial times,” Artz said.

The area became an archaeological site when Artz and his wife, Chérie Haury-Artz, rode a canoe down the Middle Raccoon River in 2010 and discovered fire-cracked rocks along the bank — rocks indigenous people used to surround a cooking hearth that were altered and split from the heat.

“We found a couple of the cracked rocks and reported it as an archaeology site,” Artz said. “I thought it would be a real good place to have a volunteer team. That was the first thing we did was look for artifacts in the cut bank.”

A cut bank, shaped like a small cliff, is formed by soil erosion as the water comes into contact with the bank.

We divided into groups to tackle several tasks — using a bucket auger to dig down a meter or more, every 10 meters from the bank, showing how far away from the bank people worked and how long ago they were there; digging a 1-by-1-meter square to sample a larger area; and examining the soils lower down along the bank.

The two of us started out working with Artz’s wife, Haury-Artz — an education assistant with the Office of the State Archaeologist at the University of Iowa whose specialty is animal bones — and two other (more experienced) diggers, Claire Teusch, 17, a high-school senior from Jefferson, and Emily Randall, 22, who works for the Iowa Department of Transportation in Ames as a cultural resources assistant.

Rebecca used a sifting screen to filter the dirt that Haury-Artz dug from the ground with the bucket auger, forcing stubborn clay-based soil through the screen to isolate anything that wasn’t soil.

After more than an hour, she found one tiny piece of gravel that Haury-Artz assured her wasn’t from indigenous people.

She also found a worm.

Others were more successful; Teusch and Randall found several pieces of fire-cracked rock about 10 meters closer to the bank than where Rebecca stood, while other volunteers found chert arrowheads that had been left behind.

The discoveries confirmed once again that groups of people from post-glacial times had used the land we were now standing on to cook and find food.

Annie took photos and interviewed archaeologists and volunteers, taking a few breaks to watch Rebecca break her back sifting through piles and piles of dirt in search of just one piece of fire-cracked rock — or at least another worm.

And she was still holding out hope for some small sign of dinosaurs.

But we had work to do in Carroll, and after a few hours, the heat had become too much and Rebecca’s arms had grown tired of sifting. So we headed back to the air-conditioned car.

The rest of the group stayed until about 5 p.m., and we applaud them.

The day went well, Artz said, with the dig’s participants getting a lot of digging done and discovering quite a bit. During the day, the diggers also found another archaeology site that no one had known about prior to that dig, on a rise not far from the cut bank.

We had never been part of an archaeology dig before — as it turns out, it’s paleontologists who find dinosaur bones, not archaeologists, and we didn’t come across any signs of the prehistoric creatures in Coon Rapids that day.

Still, it was fascinating to know that a place so close to our home once housed a glacier and later helped nomadic people find and cook food.

“It shows that western Iowa today is connected with not just a small town — it’s part of a bigger continent,” Artz said. “It’s part of a bigger culture. We’ve always had ties to the world beyond Iowa’s borders.”

Artz said he believes the artifacts we found were left by people who lived in that spot briefly between 2,000 and 3,000 years ago.

“We’re essentially marking a place here where people left a record,” he said. “There were people here, and all we know of them is what they left behind. So in some ways, this is a tribute and a thank-you to them.”