A piece of pottery with decoration marks in a man's hand
Sandstrom is among a dozen anthropology students who spent summer session conducting a field study at Sherburne National Wildlife Refuge uncovering evidence of occupations that have laid undisturbed for up to 1,000 years.
St. Cloud State University is partnering with Sherburne National Wildlife Refuge to document ancient occupations in the refuge. Cultural resources management graduate students are also doing projects at the refuge on how fire affects an archaeological site and restoration of mounds disturbed during past archaeological studies.
The field was once part of a farmer’s field, so students had to look down below the plow line to find artifacts with historical significance that can reveal clues about Central Minnesota’s past, said Professor Mark Muñiz, field study leader.
Through the study they’re seeking to answer questions about how big the site is, how old it is, what cultures occupied the site and how they used it, he said.
With each artifact they uncover they come closer to the answers. In just a few weeks on site, the study has revealed arrowheads, flakes of rocks left over from making stone tools, pottery sherds and fire cracked rock.
Designs on pottery sherds can be studied to reveal which culture made the designs and flakes and arrowheads made from stone not common in Central Minnesota can point to trade taking place among people, Muñiz said.
Sandstrom found an arrowhead made from Hixton silicified sandstone, a stone found only in western Wisconsin. In another excavation unit, students found flakes of obsidian, a rock from the Rocky Mountains that was traded throughout the Great Plains and into the Western Great Lakes.
“We’re getting some really interesting connections to other parts of North America with just the raw materials we’re finding here,” he said.
This isn’t the first time St. Cloud State archaeologists have studied sites at Sherburne National Wildlife Refuge. The university’s first field studies were conducted in the refuge in the 1960s-70s led by professor emeritus Richard Lane, and 2018 marks the 50th anniversary of the St. Cloud State archaeological field school.
It was in reviewing reports from those first decades-old studies that Muñiz came across a reason to investigate the site.
A report from a 1974 field study contained a note that the location should be investigated further because of reports of artifacts found in the area. There was no indication that the site was investigated at the time, so Muñiz included it in the 2018 summer session field study.
When the class walked out for an initial investigation in early June, they knew right away they had found a special site, he said.
Just walking in the field students were finding flakes and arrowheads without disturbing the ground.
Sam Mick pulled an arrowhead out of a gopher mound, and that’s where the students put one of their first excavation units.
The unit didn’t reveal any artifacts below the plow line, indicating that it was a later occupation. Other units in the site have proved more promising, with artifacts being revealed in every layer of earth they uncover.
Sara Robbins works in an excavation unit during the field study.
In one unit, Mick and Kylee Glen found a sherd of cord-wrapped, stick impressed pottery that features design elements from the original pot.
“When we find pieces like that it is really exciting for us because when you get to the decorative portion of the pot, that helps you narrow it down to … who made it,” Muñiz said.
Sandstrom’s unit has been one of the most prolific for artifacts, in just one 5-centimeter level of their 1-meter square unit Sandstrom and her partner Azenette Vega recorded 16 artifacts from an ancient activity surface.
The artifacts included flakes from making stone tools and fire-cracked rock, which were the remnants from rocks used for cooking by dropping them into a water-filled pot to boil water and heat food, said Courtney Kujala, anthropology student.
When the rocks cracked too much and began breaking up in the food, they would be discarded. With the amount of artifacts being found and the soil characteristics in Kujala’s unit, Muñiz is hopeful that the group has found a midden, a place where occupants discarded flakes, food, broken pottery and other waste items. If the location is a midden, it would have much to tell about how the people lived and used the site, Muñiz said, adding that he plans to explore the possibility further during a future field study at the site.
“Middens are not super rare, but to find one that’s intact, that hasn’t been plowed, looted or had a road put over the top is uncommon,” he said. “That would add a really important component to an already significant site.”
