Monday's Riddle! Gathering Moss...

This riddle is close to my heart- and I can't wait to post the picture! ~ F

When you walk, I stand under your feet, whether on the ground or high in a peak. I am one of the seeds that sows this place- I watch in silence with a stoney face. I am solid and true like any good boulder- for there's nothing out there that could possibly be older. Your history is read in my lines; some in the past have left me their signs. When I roll, I gather no moss- when I do, it may be tricky to get across. I am always around, though it seems never there, except in the woods when your in need of a chair. 


What am I?

Check back later to get a clue...