After speaking with Ben, I am continuing to develop the idea. I am thinking about having around 5-10 shot codes at certain points around a tree showing the shadows at different times of the day. Essentially like a sundial as was pointed out as I was browsing through some of my shots. I am using the shadows idea to have different shadows at different times showing the space in time. Almost like a time machine.
Maybe the shadows could relate to peoples perception and movement around the space.
So it could look like this mock up.
After doing a bit of research on shadow art, the vast majority didn't appeal to me so I haven't included them on here. A bit boring and bland. But then I found Neffs work, and I'm very impressed. He captures the shadow in a very memorable way and I hope to capture shadows in a similar way. Without chalk!