Mount Heyburn, North Buttress of the East (Third) Summit, Sawtooth Mountains. On October 15 my wife Shari and I climbed an obvious buttress on the north face of Hayburn’s east summit. Difficult climbing involved crack climbing. On the fifth pitch I let loose a large rotten flake, which fortunately missed Shari. Some of the rock was extremely weathered and rotten while other parts were quite sound. There was a short overhanging finer crack on the summit spire. NCCS III, F9, Al.