Took a trip to the WA coast just North of Cape Discovery. Walking a trail and heard a tree knock or to be more accurate three rapid knocks. Possibilities are some human BFRO type but have no idea why they would be that far off trail. The knocks were too rapid to be tree banging in the wind. So that leaves a single event by a woodpecker that did not repeat knocking or a BF. On the way back out, did hear another repeating knock of much longer frequency in the same area but on investigation discovered it was a tree swaying in the wind knocking against another tree. Things like this make me furious at the BFRO. If BF knock, and most think they do, knocks used to be a way to know one is nearby. However, now that humans are performing the knocking behavior, it is more likely to be a BFRO type than BF, so knocks are not positive indication of BF activity. I am surprised that the BFRO does not advocate using stompers to lure in BF with fake footprints too. Makes as much sense as doing tree knocking when they have no idea what it really means.