Has anyone tried the Columnar variety of European Hornbeam as bonsai? I picked up a few from my local garden nursery last year and stuck them in the ground uncertain of what I wanted to do with them. Today I picked up 5 more and will use these and the other 3 as a hedge. They have a 4/4.5" base and 2/2.5" trunk and at $45, I think they're mighty cheap. I was just wondering if their upright growth habit is more of a battle than what it's worth to bonsai?