Anyone know the ratio of mature tree size vs container size? I am in Zone 7 in Abbotsford BC Canada, (similar to Seattle climate). I want to plant a medium to large hardy tree that has a tall, wide canopy when it matures (approx. 30+ ft tall and at least 20ft+ wide) and preferably has attractive foilage or blooms at some point in the year, such as a maple or flowering cherry). I'd like a fast grower. I want to put it in a container but don't know what size I need. I am looing for ideas. The container is going to be 14" wide, 24" high and 4 ft long and will be bottomless with roots being able to escape through the bottom into the soil beneath which is part tp soil and then clay soil. I know the size of the pot/container will be relative to the tree I choose but does anyone have a formula or idea of what size of maturity type of tree etc I can have in a container like this? What hardiness should I be looking at, too, since the young roots in the early years will be above ground in the container before excaping into the landscape?