A RANCHER I MET while walking from Charlson to Watford City told me I should camp behind the Lutheran Church, its hard white steeple rising above brown spring fields on the North Dakota prairie. I knew what lurked on the horizon, and the churchyard seemed as safe a shelter as I was likely to find. So, on that May evening, I dropped my backpack on a square of green lawn behind the building and staked my tent, crawling in to sleep.
Frogs in a streambed croaked. Buntings darted between stout gravestones carved with names of settlers from a century before: Olson, Johnsrud, Rolfsrud, Larson, Hansen. I had spent the last four days moving step by step across open prairie — and when I settled down to sleep I felt more…