The island we camped on two nights ago has no name. On the 2007 U.S. Army Corps of Engineer maps -- the latest edition of the gold standard, for canoe and tow pilots alike -- it does not appear at all. This, to me, is the power of the river: always renewing, always creating.

A glance at satellite imagery makes clear why there is an island where there is: the Corps built a dyke, and the dyke stopped the sand. The Mississippi is a muddy river, which means it is filled with dirt, but when the river slows, or the dirt is stopped, it drops out, and builds land. Then plants arrive, setting their roots, holding this new soil together, willows most of all. (Willows, I’ve noted, are resilient: we’ve seen them growing up even through the riprap, the stones thrown down at the river’s edge to keep the bank from eroding away. No wonder no trees are allowed to grow along the levee.) Moss and shrubs grow up from the hardened mud. Beaver and deer find their new home. An island is born. Eventually, some flood will rip it away, or attach it to the mainland: an island will die, in other words. (Oxbow lakes, too, have a live-and-then-die life cycle.)

Rivers are all about change, in other words. There is some change that I wish hadn’t happened: now that the water is warming, for example, the silver carp are beginning to leap from the water. We’ve seen invasive mustard garlic scattered across the islands where we camp. As a few members of the expedition have pointed out, though, there is one invasive species far worse than any other. Human beings, of course.

We are camped now at the bottom of Little Cypress Bend, but I see no cypress trees; I doubt there has been a cypress here since the days of the steamboats, when the forests were cut down all along the river to keep the engines churning. We have cramped the river in this narrow floodplain, and in places we are trying to narrow it further still. We have built our dams and dykes. But the river keeps doing its work, keeps on building its islands, and will do so even once we’re gone.

(For those who want more quotidian information: we are camped now at mile marker 861, on Joe Eckles Towhead, with a storm raining down on us now. Yesterday we resupplied in New Madrid, Mo. -- and were wowed by the town’s generosity -- and tomorrow, if the weather cooperates, we should expand our crew when we arrive in Caruthersville, Mo.)