Got a coal with white pine on white pine with bowdrill today. It took a fair amount of speed and the coal took a long time to coalesce. I had three coals go out in 3 or 4 seconds before I got one that would stay burning. The white pine’s dust pile burst into flame after sitting in the wind for five minutes or so.
I intend to experiment further with the dust pile turned tinderbundle. It may be useful if tinder materials are rare.
Also got a coal with sumac.