I would be interested in doing more bicycle trees perhaps tipped at an angle as a fence or making a square. This project was done with a single crab apple planted small about as big around as a thumb and took 12 years. The same can be accomplished much faster with a larger tree to begin with, or faster growing tree species like Poplar or Sycamore.
This piece just ended up finished. It seemed "done" at a certain point. I cut it and saved it as an artifact. I couldn't imagine it growing any further. I don't usually think in terms of an end product or arrival because I'm so involved in the process. But tree projects in which objects are included into the growth are sometimes over and completed. There wasn't any where further for this to go other than yet another wheel being added above. So I felt the exercise complete.