If you have any groves of American Beech or Quaking Aspen near you there are likely some arborglyphs on one of more of them.  

Google says vandals and lovers historically target these two species due to the texture of their bark and that the carvings leave permanent scars for the rest of the life of the tree.

I am going with lovers on this tree, the heart is a little wonky but it probably impressed whomever the carving was for.

Show us your love story without people today.