I second that about being plentiful and easy to collect. They are quite invasive here in Illinois and I've been collecting them from the wild, not sure if they have infected your area but look into it as a source of material and helpful to your habitat locally. If they are invasive locally look at sites near shaded rivers, creeks, and streams. They are easy to identify but if you go in the fall they will be very visible of course.
The only thing to know with these is they only put out one flush of growth in the spring, once that hardens off they are done producing vegetative growth for the year. I have heard you can possibly get another flush if they are healthy and you cut back severely after first flush hardens. I have no experience defoliating them but would love to know if anyone does?
They grow very predictably which makes pruning choices easy but the single flush makes for slow development.
Resisting the urge to remove growth before fall is the hardest part but after working on some for a few years it drastically increases thickening, wound healing and of course energy for the next season. Although some should always be removed, chiefly any place 2+ branches are sprouting from as it can create bad swelling.
They heal well, backbud very well, heal wounds quickly if done right.
They prefer some moisture but can tolerate drying out pretty well.
They are not shy of showing you they need water though as they will droop dramatically especially before new growth hardens off.
Will grow is most anything I imagine but having them in inorganic bonsai soil is very helpful as the very fibrous root system can be very hard to disentangle and pick clean of organic material initially.
They can handle very severe root pruning. I've pruned 90% of roots off them not that I'm recommending it but I'd go very hard first time and just get it all sorted out.
They will fill most pots in one year and should be repotted annually.
I'd take most of what you wired down to one or two internodes as well. You will see them backbud a bit during the fall prune but more will pop in the spring as well. You may decide to regrow the tree entirely after you see what it pushes out next spring.
No major diseases that I know of. Best fall color if you keep them in full sun but they don't mind shade and if you can't be there to water that's a great option. They are pretty cold hardy and need minimal winter protection but keep some moisture as they do require that.
They make great bonsai in my opinion and under utilized. They are pretty much care free and having a few trees you don't have to worry about is very nice
One won noelanders trophy not long ago
Hope that helps just trying to save you some time as I often see inaccurate or little information on them.
. Movement? Still mostly straight branches
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