Tuesday, March 17, 2009

A Piece of Wood

It's not really much to look at. A little bit too big to call a stick, but not quite big enough to call a log, the piece of wood is a more or less straight, 8 inches long by about an inch in diameter. Black on one end, fading to gray on the other, it's splotched here and there with an ocher colored mud.

It smells funny, too.

I pulled it out of the bank of a small stream close to my home. This small stream runs through an open field, a former pasture that used to graze a herd of cattle. For what ever reason, the farmer who's land it is that the creek runs through got tired of grazing his cattle out there. The cattle went somewhere else, and all that's left now is the creek running through the open field.

I was there at the creek with my seven-year-old daughter. We had met a couple of friends of ours there, one a Habitat Biologist with the Wisconsin Department of Natural Resources, the other his seasonal assistant. Together, we were waiting for more people to show up, all of whom were going to help out with a restoration project that still another friend had organized. The project centered on restoring this stream, subject to a century of non-existent land management practices, to a point where it's wild brook trout would be able to not only survive, but reproduce, as well. Shocking surveys indicated that only a very few of the small char lived in the cold, clear water; the streams sediment load allowed only the barest minimum of cover for the fish to survive.

While we were waiting, my friend caught me up on the details of the project. He showed me where the wooden "lunkers" had been placed; basically a large wooden pallet, a lunker is placed along the bank of a stream, under the water. Rock is piled on top of the structure, and dirt is bulldozed over that. Seeded with grass, it eventually becomes a cut-bank, accomplishing a number of things all at once. The wooden structure becomes home to many types of fish, both trout and other species. The once collapsing banks are now stabilized with turf-covered rock, and the now narrowed stream, swifter and colder than before, is now better able to scour down to its original gravel beds.

My friend, the biologist, mentioned that he had pulled a very interesting piece of wood out of the sediment making up the banks of the river, down underneath the water.

"I've sent it in to be Carbon 14 dated, but I'm pretty sure it's between 4 and 8 thousand years old," he said.

Come again?

"There a bunch of it down here - here, let me show you." We walked over to the bank, and he pointed down to the edge of the stream. Sticking out of the bank under the water was a snag of wood. I stumbled down to it and pointed a questioning finger at it.

"Yeah, that's one of them. They're all over down through there," he replied. My friend went on to explain how you could tell the ancient lumbers approximate age by the angle and depth of the woods deposition. Below the agricultural runoff of the previous century lay the former stream bank. Below this lay gravel and fine grained, wind blown loess clay beds deposited by the glaciers. Sticking out of this was an ugly piece of wood, a little bit too big to call a stick, but not quite big enough to call a log.

As I grabbed hold and pulled the stinking, mud-covered branch out of the bank, my imagination swam with the possibilities...

By its appearance, it was one of the primary branches from a large evergreen, perhaps either a hemlock or a spruce. It is almost certain that the tree provided shade and cover to a wide range of animal life: 1,000 years ago bear, carnivorous cats, rodents and ungulates such as deer, elk, moose and woodland caribou prowled the Wisconsin woods. If the piece of wood turns out to be truly ancient, that is, 6,000 to 8,000 years old, then it's quite possible that maybe a wooly rhinoceros or even a mammoth had browsed along it's branches.

The tree might have shaded this same creek, and while it's almost certain that this little river was running then as it is now in this general area, it is anybodies guess where exactly the stream bed lay that long ago. It would take a major excavation of the entire area to figure that out, and that isn't the point of this project. But if this was the streams original bed, brook trout were here. It would be something like a poem to say that the fish flashing beneath our feet were ancestors of Pleistocene brookies, but that is probably not the case: most of Wisconsin's brookies, except in a few rare cases, came decades ago from Maine, brought here after the original stocks were choked out of Wisconsin's streams by logging and agricultural runoff.

If the branch turns out to be not quite as old as we hope, the possibilities still remain amazing. Perhaps the tree this branch came from sheltered some of the earliest Wisconsinites. I watched my dark haired daughter playing in the creek; I could imagine a similar daughter 2,000 years ago, playing under the majestic evergreen that my stick came from. Kneeling at the base of the tree among its gnarled roots, she would have laughed into the shady, sunlit gloom as the babbling brook splashed her. Or maybe she gazed at an approaching thunderstorm from the tree, clinging to my branch as she worriedly watched the purple clouds build in the West, lightning walking the path of the primitive gods towards her and her families camp...

It's not really much to look at. A little bit too big to call a stick, but not quite big enough to call a log, it smells funny, too. But the story this branch tells is amazing; it's history as vast as the centuries.

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