Here's the largest (as in thickness) tree I have at the moment. It is a Crape Myrtle (Lagerstroemia Indica). The pot is a Chinese one and measures: 750mm x 600mm x 200mm deep. The tree measures 550mm across the base (soil level) and stands 500mm high. It was part of a huge trunk we dug out of a garden some time ago. We cut the trunk into six segments - the other two I have are a bit smaller across the base. There was very little root left on any of the segments because they had spread so far away from the trunk we had to cut a most of the heavy roots away. As far as I can remember, this one had maybe six very thin feeder roots left when we'd finished. The first photo is how it looked last summer and except for feeding and watering, it hasn't been disturbed in the black plastic tub. This spring it put out at least six times the foliage so it's taken quite a while to recover from being ripped out of its 52 year old bed. The next two I took today after pruning it heavily and potting it up for the first time. The original thin roots had thickened up considerably and over the entire base it had put out a huge mat of very fine feeder roots. I cut the thicker ones away leaving just this lush mat of feeders. Before I pruned the foliage, it had quite a good overall shape but was made up of long thin branches with leaves all the way along. If I'd left it like that, the leaves inside the canopy would have died off leaving these straight 'sticks' with a couple of leaves on the end. So, by pruning the branches back to two or three leaves will encourage it to put out a lot more shoots over the next month or two. Especially as it is in some new fertile potting mix. At the time we dug this out, I only had a bag of 'El Cheapo' potting mix ($2.95) and didn't have time to go and get some decent stuff, so I used it. It's now somewhere about 2 years since we dug it out and the top 10cm of that potting mix still hadn't broken down - it was still brown - don't know what it was made from, but it was absolute rubbish!
There is a lot of dead wood in the trunk especially in the middle and on the right side between the two pairs of red lines in the fourth photo (looking at the tree), and when I get around to it, I'll brew up a good batch of Lime/Sulphur and bleach it - should look quite good with bleached 'driftwood' curving up through the centre and the side of the trunk.
In Bonsai terms this tree would be medium/large (as in width, not necessarily in height). I can just lift it but it is really a two man job and that makes it a medium/large - a four man lift is classed as a large one.