Rock...the nurseries here are limited at best and I would not want to depend on them for anything. Like the maples I recently ordered and received...had to go online and find the ones that I wanted and get them shipped. They were grown for bonsai and are pretty good size etc. They will not make it through a winter here most of the time so I will have to store in shed with minimal heat. Same thing is going to happen with the oak. If I am going to spend the time and money with something, it needs to be very cool and pretty (fall colors), and I don't care if it is zoned for here or not. Obviously it could not be a tropical, but if it is a zone 6 and I'm a 5 that's easy to take care of. I will probably never leave any bonsai out over the winter here because of sub 0 and wind factors and I don't want to be out trying to move them to cover when I see that coming. The shed stays at 30-40 F and I have a temp monitor in there. Peter