Archaeologists seek cultural evidence in Sherburne refuge

Jacob Fritz uses a wire screen to sift soil for ar
In this photo taken Nov. 27, 2015, Jacob Fritz uses a wire screen to sift soil for artifacts.
Dave Schwarz | St. Cloud Times via AP

The biggest surprise to emerge from an archaeological survey that started late this fall in Sherburne National Wildlife Refuge is what hasn't turned up.

A site such as this — land where Native Americans once hunted bison and elk, where the St. Francis River provided prime campsites, where Europeans once farmed -- holds promise.

There's potential to find evidence of Native American cultures, of fur traders and farmers.

"We've been in some terraces like this that jut right into the watershed and the river runs right by it and it's flat and if you were ever in a canoe and wanted to just chill out for a while, that's where you would go," said Joe McFarlane, project manager and owner of St. Paul-based McFarlane Consulting.

"Nothing."

On the day after Thanksgiving, with the St. Francis River providing a shimmery, sunlit backdrop, McFarlane dug shovel test pits with Jim Cummings, principal investigator, and Jacob Fritz, who is pursuing a master's in cultural resources management at St. Cloud State University.

The St. Cloud Times reports that the survey, which is to wrap up in May at a cost of no more than $76,850, is one element of a $520,000, 968-acre oak savanna restoration. The largest restoration in the 30,700-acre Sherburne National Wildlife Refuge's 50-year history includes a long-planned timber harvest, which instigated the archaeological work.

By the time the ground froze in early December, the McFarlane Consulting crew had surveyed about one-fifth of the 2,145-acre project. After 354 shovel tests and initial walking surveys, they'd turned up two prehistoric and two historic sites.

Work will resume in the spring, earlier if there's a thaw.

Jim Cummings measures
In this photo taken Nov. 27, 2015, Jim Cummings measures the depth of a hole dug while searching for artifacts at the Sherburne National Wildlife Refuge in Zimmerman, Minn.
Dave Schwarz | St. Cloud Times via AP

"I'm most interested in avoiding burial mounds from thousands of years ago. Central Minnesota has a lot of earthen burial mounds that have been found over the last 100 years," said James Myster, the U.S. Fish & Wildlife Service's Bloomington-based regional archaeologist and historic preservation officer. "If they've identified any of those, we're going to put a buffer around them and completely avoid them during the timber sale."

Myster said FWS is also interested in prehistoric campsites or 100-plus-year-old farm sites.

In an average year, the eight-state region handles 10 archaeology projects. Sherburne's is among the largest.

It started with pedestrian surveys. Walking 10 meters apart, the crew scanned the earth for visible features such as burial mounds. McFarlane estimated each of the five tracts surveyed turned up 20 to 30 spots worth a second look. They marked those with a GPS and later returned with a shovel.

On this day in late November, the pointed shovel sliced easily into the sandy soil. While bits of tangled roots turned up in the screen, barely a pebble was found in the fine, reddish-brown earth.

The crew, only three of the usual six, worked in a well-practiced rhythm. Lay out the small blue tarp. Set up the wooden frame that holds quarter-inch hardware cloth taut. Shovel, precisely, a hole 40-45 centimeters in diameter and 50-70 centimeters deep, depending upon when the soil type changes. Run a gloved hand over the screen, loosening the soil from the roots. Fold up the screen. Grab the edges of the tarp. Funnel the dirt back in the hole. Tamp it down. Make notes. Move to the next spot.

"It's like a presence/absence kind of thing," Cummings said. "That evidence is arrow points, spear points, pieces of ceramic pots. It might be the flakes from the manufacture of stone tools. Bone that has been altered from cooking. ... Other things are granite or basalt rocks that have been cracked in a way that indicates they have been super-heated beyond natural causes."

Discovery of any evidence equals a positive shovel test.

"It tells us something was going on here. It doesn't tell us what was going on here. But it gives us an opportunity to tell the refuge managers that this is an area that should be avoided," Cummings said.

A report goes to the FWS and the Minnesota State Historic Preservation Office. (This is the first phase. The second would involve more carefully digging larger holes; the third would involve extracting as much information as possible from the site.)

So far, there's not much to tell.

"We're surprised that we're not finding more cultural material. However, I'm confident that we will. We just haven't found that specific location," Cummings said.

Cummings reached into a pocket to extract one of the Sherburne artifacts: The results of Shovel Test No. 86, a piece of Tongue River silica, a little bigger than a quarter.

Tongue River silica isn't something you'd find in the Anoka Sand Plain, which includes Sherburne NWR. It's found to the northwest, in glacial moraines, but it was traded and used widely. Judging from the grooves and flake marks, Cummings figured it was material left over from making a stone tool.

"That's not a real exciting artifact," Cummings said, returning the piece to the tiny, zip-top plastic bag labeled in black marker. "But it's one of those indicators that, because we found it in this little, small chunk of this big space, that's an indicator that there's an archaeological site there."

One reason the crew expects to find more has to do with watersheds and biomes.

The state's watersheds drain to the Arctic, the Atlantic or the Gulf of Mexico -- so anyone who followed those streams would have turned up here. Three biomes -- prairies, hardwoods and pines -- meet in Minnesota.

"Only Minnesota has appreciable amounts of all three. That's really significant. That's why people come here to hunt, camp, fish, recreate. That's also why people came here to hunt, fish, camp, survive," Cummings said.

"The excitement of it for me -- and that's part of why I like to do archaeology -- is connecting the landscape where we are to what it is we're finding or not finding," Cummings said.