Welcome to TBN (January 2014 and first post)
Marks on trees made by Bigfoot.
I am inclined to agree with Richard -- the trees may have been scraped by the limbs of felled trees as they were being skidded to the landing deck.
I think that someone has marked these trees to cut out...... not sure what they used. Wanted the marks to be visible for when a crew comes in to take them out. [[ ??? ]]] If you noticed, there are some off the trail that are marked the same...