I bought a real birch tree trunk at a local floral design supply in the flower district downtown. To tell you the truth, it looked as though it had a quick sloppy sponged white paint job on it. It looked good but so easy to replicate for the many trucks I'd need on set. As I started to test making a few out of the tons of free fabric core tubes I had here, I soon realized how complex the texture really is. Making the straight tubes (upper left) zig and zag slightly was the easy part. I used…