Dennis Myllyla thought he’d struck a fine bargain with the Michigan Department of Transportation. MDOT would get fill for nearby highway construction by dredging a pond on his farm near Arnheim, Mich., and Myllyla would get the pond.

Neither Myllyla nor MDOT expected to find a prehistoric forest too. But that’s exactly what they uncovered, about 15 feet down.

“We ran into logs, lots of logs. It was like a forest down there,” said Myllyla, who has been farming in the Arnheim area since 1948.

Forestry consultant Justin Miller was on site when the MDOT heavy equipment operators found themselves dredging up more logs than sand. Miller, who had been preparing a management plan for the forested sections of Myllyla’s property, was a 2000 graduate of Michigan Technological University’s School of Forest Resources and Environmental Science, and he knew just whom to call.

“I’ll rush right down and take a look,” James Schmierer responded. The forester from Michigan Tech was there within 24 hours.

What he saw amazed him. “We find a lot of trees lying on the forest floor, but this was the first time I’ve seen so many trees thousands of years old and so well preserved in the soil,” he said. Dozens were tangled together, some of them 20 feet long and more than 2 feet in diameter.

“What could bury a whole forest 15 feet underground?” Schmierer wondered. “It had to be a single catastrophic, violent event, and it must have happened a long time ago for 15 feet of soil to build up.”

Schmierer and his colleague, Michael Hyslop, a GIS analyst and instructor of geomorphology and vegetation at Michigan Tech, speculate that the trees were either transported or mowed down by the last glacier to move across the Keweenaw, before Lake Superior covered the peninsula. “That would make them more than 10,000 years old,” he said.

Schmierer and Hyslop have recovered some of the logs and are hoping to carbon-date them. Schmierer also hopes to identify the species of tree.

“If I had to guess, I’d say it was an elm,” said Miller, “but I really don’t know. I’ll be real curious to find out how old they are and what species.”

Schmierer plans to make two displays from chunks of the ancient trees, one to put on exhibit at Alberta Village, the Michigan Tech School of Forestry’s field site, and the other for the atrium of the U.J. Noblet Forestry Building on campus.

“And Michigan Tech is going to give me one as a momento,” said Myllyla.