Wood in Upper Blue
Just took a run down the Upper Blue; there's definitely some wood.
A few hundred feet above boulder crk (I think), at the entrance to the first moderately significant drop there is a large river wide strainer. It could be boofed on river left, though we portaged river right. Recommend portage/scout river left (river right sucks), but there aren't great eddies after it becomes visible. There were some rafters trying to drag it out of there, I'm not sure if they were successful.
Next wood was river left at what appeared to be an old railroad trestle. It looked like it was cut, so it probably has been there for a while. It was my first time running this stretch, so I'm not sure.
3/4 through the run there was another large river left strainer. After scouting we determined it could be run safely river right, but at this level there were some very large shallow rocks in the river right line. It required a moderately difficult move to navigate the rocks. If you flipped you could easily be sucked in to a potentially deadly situation. Use caution.