"Snags" in the Missouri River, somewhere in Nebraska.
Photo by Jim Peterson
Sometime in the more or less distant past, springtime floodwaters deposited rich loam on the floodplain here, then ran on downhill toward the Gulf of Mexico. At the water's margins cottonwood trees, Populus deltoides(1) like these took root in the hospitable soil, reaching down to drink, holding on for dear life.
Annually, the river sips away at the banks and claims what it left on them back then. In due time the cottonwoods succumb to the river's subversion, lie down in the depths and die, and become snags. They are submarine sieves, straining through their flailing limbs and naked rootwads all the flotsam the river brings their way. Sometimes, even today, they trap boats and, occasionally, boaters. They are open manholes on the riverine roadways of the West.1
All the snags' branches wave under the water much as they blew in the wind. Those that protrude above the river's surface also oscillate in the current, as if to warn sensible creatures away. These are called sawyers.
Captain Lewis recorded an encounter that Sergeant Ordway and Private Willard had with a gang of sawyers on the night of August 4, 1806, somewhere downstream from the mouth of the Milk River.
Ordway and Willard delayed so much time in hunting today that they did not overtake us untill about midnight. . . . In passing a bend just below the gulph, it being dark, they were drawn by the currant in among a parsel of sawyers, under one of which the canoe was driven and throwed Willard who was steering overboard. He caught the sawyer and held by it. Ordway with the canoe drifted down about half a mile among the sawyers under a falling bank. The canoe struck frequently but did not overset. He at length gained the shore and returned by land to learn the fate of Willard whom he found was yet on the sawyer. It was impossible for him to take the canoe to his relief. Willard at length tied a couple of sticks together which had lodged against the sawyer on which he was and set himself adrift among the sawyers which he fortunately escaped and was taken up about a mile below by Ordway with the canoe; they sustained no loss on this occasion. It was fortunate for Willard that he could swim tolerably well.
Snags and sawyers that break loose during high water can collect into log jams, which the French-Canadian boatmen with the Corps would have called embarrases—"hinderances."—which could pin a boat broadside against its upstream edge, and possibly cause the current to capsize it.