Is anyone able to direct me to discussion on the design of mature Acer buergerianum?
Any pictures I have seen seem to illustrate multiple branches coming from the same area of the trunk, bar branches, etc.
There’s one possible reason you’re seeing bar branches on tridents, and that’s because of how thick they get. They’re natural fast growers and very vigorous, so they develop a thick trunk quickly.
Once your tree is at a certain thickness, two (or several even) thin branches coming out of the same horizontal plane won’t really be able to affect the girth of the tree that much, or at all (aka won’t cause bulging/inverse taper).
It’s impossible to avoid sometimes on larger trees, but it doesn’t pose a problem. It’s not something to try to include in your design on purpose though. In general, treat it as any other deciduous / acer species, and make sure to have a thick trunk to really try to emulate that trident feel.
Thank you - that clarifies some of the mystery!