A Goodhue, Minn., man stumbled upon wood buried deep in the ground while doing excavation work in Carver County last summer, later discovering the artifacts were 14,000 years old.

The uncommon find, which survived the last Ice Age, offers a window into a time when parts of Minnesota were covered in glaciers. The wood split into pieces during excavation — the larger of two chunks, which is 2 feet long and a few inches in diameter, found a home last week at the Carver County Historical Society as the oldest item in its collection. The smaller one will stay at the University of Minnesota's Bell Museum of natural history.

Joel Kassen was installing new sewer lines in a Carver farm field in June when he noticed his excavator was hitting wood. He found that unusual, since he was digging about 18 feet underground — deeper than anyone had dug in recent centuries and far below where a log would typically hide, said his brother, Gary Kassen.

Joel Kassen carefully scooped out the relic and brought it to his brother's Chanhassen home. The pair both have an interest in geology and history and suspected the wood, which had remained solid, "was from the glacial period," Gary Kassen said. "I was excited — that's something I've always hoped I would find, or I would see."

The rural area where the wood turned up is across from Hwy. 212 and a Fleet Farm store, Gary Kassen said, and under development as a business district. There's a new gas station nearby, and a road now covers the hole where it laid.

His great-grandfather's farm, where the family first settled, is just 10 miles from the excavation site, south of Cologne, Kassen said.

Gary Kassen, the engineering director for hydraulics at CNH Industrial, had contacts at the U. The find ended up at the Bell Museum, whose staff sent it to California for radiocarbon dating.

The wood, they determined, is between 14,033 and 14,433 years old.

About 10,000 to 12,000 years ago, Carver County was covered in glaciers, though the glacial period was ending. A glacier must have picked up the wood as it moved, said Tim Whitfeld, collections manager at the Bell Museum's herbarium.

When the ice sheet melted, the glacier deposited the items it had collected, he said, including the wood.

"It was really cool to actually verify [the age]," Whitfeld said. "It provides a date for when there was glacial activity in the area — that's an interesting, significant finding."

It's somewhat uncommon to come across such wood, Whitfeld said, and discovering it was "pure luck," since a person wouldn't know where to look. It took a "sharp eye and a keen interest" to recognize it, he said.

The wood — which is probably black spruce or white cedar — is the only item Whitfield knows of in the Bell Museum collection that comes from that glacial period, he said.

Whitfeld said the museum wants to do an anatomical study to nail down the wood's species, and officials hope it can be displayed as part of a Minnesota natural history exhibit.

The new artifact is also unique to the Carver County Historical Society, which is a registered repository for archaeological artifacts.

"This is, for our collection, the oldest item we have," said Jeremy Murray, the historical society's curator of collections.

While it may be just a piece of wood, to hold it in your hands is exciting, Murray said, adding that it may have survived because it was under the water line where oxygen couldn't break it down.

"It just speaks to how well some of these things can be preserved under the right conditions," he said.

Erin Adler • 612-673-1781