This is Roald Tweet on Rock Island.
Of all the trees that inhabit the Mississippi River Valley, the most common are certainly the several species of willow that grow thick on the islands and bottomlands and along the sloughs of the main channel.
The willow is one of those trees that gets no respect. Its supple branches give it a certain use in rustic furniture for front porches or cabins, and its green twigs in spring were once used for willow whistles back when boys made things for themselves. But it's too soft and too plain for furniture, too fast burning for fireplaces, and too short lived to take home to the backyard. Winter ice bends willows to the ground, they give way to hardwoods, to maple and oak and walnut, without a fight, retreating to the wet ground no other tree wants. Willows are the wimps of tree-dom.
Or are they? Not on the Upper Mississippi. In the 1870s, willow became the weapon of choice when the Corps of Engineers was ordered to deepen the channel for steamboats. Thousands of acres of scrub willow lay handy in the shallows. From these willows, the Corps wove mats which they submerged with crushed rock, layer on layer to create the long wing dams reaching out from each shore. These dams constricted the flow of water to the center of the river, where it scoured the bottom and deepened the channel.
Wing dams were replaced in the 1930s by great concrete locks and dams. The concrete in those dams lasted fifty years before crumbling to the point of needing millions of dollars of repair and replacement. Meanwhile, nearly all of the hundreds of miles of willow mat wing dams are still in place doing their job. In fact, cut a small section of willow from one of the dams, and it still floats, undamaged by a hundred years under water.
Before I moved to Rock Island, and came to understand willow, I had often puzzled over one of the lines from an old Shaker hymn. "I will bow and be simple, I will bend and be free," go the lines, "Just like the willow tree."
"Bend and be free." The Shakers were inspired by a kind of inner wisdom, but they also knew their willows.
Rock Island Lines with Roald Tweet is underwritten by Augustana College, Rock Island, Illinois.