I returned 15 months later to see how my 2015 wood opticons were fairing on the PCT. I didn't expect to see any one of the five I planted in the ground early in the summer of 2015, but there were still two there. They were placed in the ground several feet from where I had initially installed them. Awesome! This meant individuals had interacted with them with some degree of curiosity and care. The slides were no longer in the viewers however. And one of the slide holders was on the ground...no longer attached to the top of the vertical element. Last month in August while camped down from the trail I came back the next morning after the initial find to see that a PCT backpacker had already interacted with them and placed the slide holder on the ground back up on top of the vertical element. So this interplay happened just overnight from when I first spotted them... which makes me wonder perhaps if one or more of the other wood opticons are elsewhere, placed by a backpacker's hand with a curious eye.