A mastodon tooth more than 8 inches long turned up on a stream bank in Wisconsin, state officials say.

Cale Severson, a Department of Natural Resources employee, discovered the huge tooth while working on a trout habitat project in Grant County in southeastern Wisconsin, the department said Friday.

What Severson calls the "find of a lifetime" came as he examined rocks that had been dumped by flooding.

"I noticed something really odd in that pile -- seeing just two of the five cusps -- and realized it probably was not a rock at that time," he said. "I grabbed it, and out came the 8.5-inch-long molar."

Work on the stream bank was suspended while Sherman Banker, an archaeologist with the Wisconsin Historical society, examined the area.

Banker said the find -- from a juvenile mastodon -- was unusual but not of great scientific interest.

The mastodon, an enormous, elephant-like mammal, roamed southwestern and southeastern Wisconsin during the Ice Age.