How cool! My wife and I both looked at this and thought initially it was just tree bark and thought it was great. Then the forest came out of the background and it's amazing.
Thanks for the comments. This is my first submission here after discovering this site today. I didn't have to do much with this photo in PS. All I did was desaturate, bumpe up the contrast on the trees in the foreground, and add a blue in the duotone.