WHITEWATER WILDLIFE MANAGEMENT AREA – On a recent day, Bob Tangen gazed to the top of one of southeast Minnesota's many bluffs, countless of which in the region are blanketed with mature northern red oaks.
But the bluff that was the focus of Tangen's attention was largely devoid of trees, having been logged a few years ago.
Whether the hillside, which lies within Whitewater Wildlife Management Area (WMA), will ever again be graced with oaks and the deer, turkeys and songbirds they nurture is unknown.
"You log down here, and unless you've prepared the site ahead of time and care for it afterward, pretty much what you get in place of the trees you cut is buckthorn,'' said Tangen, a retired Department of Natural Resources Whitewater WMA assistant wildlife manager.
Beautiful as they are, oaks exist in southeast Minnesota as much by chance as design. Wildfires that swept across the area before settlement helped propagate these majestic trees naturally by clearing forest understory and allowing young oaks to regenerate in direct sunshine.
As the region was settled by pioneers, many hillsides were grazed and burned, which again provided an ideal environment for red oak, as well as American basswood, sugar maple and prickly gooseberry.
In the years since, as these and other hardwoods have matured and fires and grazing in the southeast have declined, shade-tolerant species such as buckthorn — an invasive plant that is extremely difficult to eradicate — have thrived.
Tangen, along with his former boss, retired Whitewater WMA wildlife manager Jon Cole, says that planned, periodic logging of selected tracts within Whitewater's 27,000 acres benefits the forest and the fish and wildlife those trees support.
Indeed, DNR wildlife managers throughout the state's 1,440-unit WMA system, which blankets some 1.29 million acres, consider forest management to be among tools they regularly employ to sustain plants and animals.
"It wasn't just oak cuttings we would include in our planned timber harvests,'' Cole said. "Deer and turkeys, of course, love oaks and acorns. But other birds are more dependent on cottonwoods and willows, for example, and in the cuttings that were part of our 10-year Whitewater WMA forest management plans, we also included those species.''