I'm coming back to this smart phone posting to add some explanation: we had come in to Lake City from an 80-mile ride on Tuesday, July 27. In the morning, as I wheeled my trike down the hall in the motel, I noticed that one tire was uneven. It had developed a bulge in the casing and appeared to have gotten some cuts in the tread. We did ride on some bad surfaces our first day out.
We tipped the back trike up to the side to change the tire. Fortunately, we had brought spare tires with us -- two of them, since they also serve as padding for the front wheel when it rides in the trailer.
We were back on the road in short order and headed down the Minnesota side of the river to Winona. From Winona, we crossed into Wisconsin and (after a brief detour down a road that existed only on Google maps and perhaps in some long-range plan for a bike path) began the bike trail part of our tour. The four great rails-to-trails routes in southwestern Wisconsin provide a car-free way to go down the Mississippi to Lacrosse, then across the state as far as Reedsburg. The surface is crushed limestone, which is best where it is heavily traveled. In the less-used areas, the center stripe remains grassy; that's hard for trikes, because it forces one wheel to run on grass.