June 24, 2005, Middle Sister, Renfrew and Collier Gl

Having skied the more standard approaches to Middle Sister from Pole Creek trailhead to Hayden Glacier and to the SE Ridge, the NW approach via Obsidian trail and the Renfrew and Collier Glaciers had remained on my agenda for many years. I hadn't made it up this way except for an early October day hike on the excellent 17-mile loop to Obsidian Falls and 7534 ft Collier Cone, at the terminus of the Collier Glacier. For those who might be unfamiliar with the area, McKenzie Pass (5325 ft) on SR 242 is the one of the most unusual and scenic spots on any highway in the US, . The TAY report), I drove down to Sisters to pick up my Obsidian Limited Entry Permit in the outside drop box and arrived at McKenzie Pass after 10 PM. I decided to car camp here rather than continuing on a few more miles to the Obsidian trailhead and campground, worried about possible mosquito problems there (this turned out to be a very wise decision). The night was warm and nearly bug-free among the barren lava flows of the pass, never dropping below 50 F, and dawn arrived all too soon before 5 AM. I slept in another hour, took some photos, slowly packed my gear, and drove to the trailhead. Mosquitos were already out, and I made a hasty exit up the trail at 8 AM, bringing the 100% DEET along just in case. The hike was quick up the well-designed and maintained trail, with occasional snow patches as low as 5100 ft and a few deep drifts across the trail from 5400 to 5600 ft accompanied by clouds of mosquitos, which I swiftly charged through with minimal blood loss. The trail is again bare up to the crossing of Jerry Lava Flow ( and continuing on the path of the buried climber's trail directly up the drainage towards Middle Sister. The snow was already very soft by 10 AM, a sign that the snowpack had not frozen very well overnight. There were numerous sets of post hole tracks . This first slope is the steepest on the entire route, perhaps 25-30 degrees, and the snow was extremely weird and unconsolidated on this NW aspect, just like I had seen on Snowdome the day before. I was sinking 6-8" deep into the mush while skinning, but stability appeared to be good as no sluffs were released. I struggled through the mush to reach the large 8200 ft bowl beside the spectacular "Dragon's Back" rock formation (marked "Folding Rock" on some maps; see a 3-shot panorama including Little brother and North Sister, or a 7-shot 180-degree panorama wrapping around to include Middle Sister at 2 resolutions: 2600 or 5200 pixels wide).

Beyond the bowl, Middle Sister returns to view and . I reached the Hayden-Renfrew Saddle at 2 PM, with a steady 20 mph wind blowing through the gap and just as a series of lenticular clouds began to alternately obscure and reveal the summit. I had skied the 45-degree slopes of the North Ridge from the summit in June 2000, reaching the saddle from 3600 or . After a brief traverse east to explore the 8840 ft Collier Saddle on the flanks of North Sister, I continued down the Collier Glacier to about 8500 ft, where the glacier rolls over and there is a ). Until the mid-20th century, the Collier Glacier was the largest by area in Oregon, but severe recession has removed much of the glacier below 7500 ft and dropped it into second place behind Mount Hood's Eliot Glacier. From the viewpoint, it was time to angle left off the glacier into the large bowl east of Point 7722 and rejoin my ascent route near 7500 ft. The snow got very mushy and somewhat sticky as I headed NW out the drainage I had come, turning to

A double solar halo with 22-degree and 46-degree arcs above Middle Sister. The 46-degree halo (lower right) is very rare compared to the fairly common 22-degree halo (at top). Unlike double rainbows, the colors are not reversed in the two halos, because they are formed by refraction through different facets of ice crystals in the stratosphere, not by single and double total internal reflections within raindrops.