Great tree. I started a Gary Oak up here in Seattle a couple years ago too. Well, I started two (in successive years), but the first one I killed because they are indeed a bit sensitive about root work. My second is healthy and survived a bare rooting and repotting from a nursery drum into a grow box last spring. I only took about a third of the undesirable roots off -- I think I will approach that conservatively over several repottings. Perhaps Spring 2022 will be my next go at it.
I also have it in mind to craft a broom, although mine is currently trending more upright. In any event it needs some time to thicken up its trunk. Contrary to what people say about oaks in bonsai, I've found ol' garryana to be quick growing and extremely vigorous, at least in these climes it calls home. Maybe it's unusual in this respect? The shoots it sends out during its spurts are quite absurd -- they usually grow to 6-10" long within a couple weeks before the leaves on them even fully unfurl. Likewise I've heard people say it takes a long time for oaks to develop their craggy bark, but your images in this thread prove otherwise for this species!
In terms of habit, I've noticed mine likes to send shoots out radially from its apical node like spokes on a wheel, as well as straight up. It's pretty hideous when it does that every spring, honestly, like it's trying to cover all its bases by growing out at all the right angles possible, but easy enough to control with some selective pruning before the shoots thicken up too much. Have you noticed this on yours?
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