Observations from Blackwood Ridge.

We toured on Blackwood Ridge taking a look at wind slabs near treeline and buried surface hoar. We dug two test pits along our route. The first was in a wind exposed, cross loaded area on a N aspect at 7,200 in near treeline terrain (39.10134, -120.17346) In this area we encountered hard wind slab about 1 foot thick. This slab was 1F hard and sat on top of 4F- older snow below the slab. ECTN results and no cracking while breaking trail at this location.

We moved a bit higher along the ridge and dug a second test pit in a more wind protected area on a N aspect at 7,400' in near treeline terrain (39.09904.-120.17837). Here we found 8mm surface hoar buried about 10 cm below the snow surface. This was the most intact SH I have seen as a part of this Jan 18 layer. The CT produced BRK shear quality, ECT and PST gave no indication of likely propagation along this layer. The SH layer was fairly well bonded into the upper snowpack. It took some work to make it fail in a shovel tilt test.