AusBonsai

When developing Trident branch structure, should you fertilize in spring? Or is that just going to create long internode?

Fert will usually give longer internodes but be careful when withholding fert. Trees can quickly starve in small pots and frequent watering if not fed.
Low N fert and reduced rates might be safer.
You can also prune off any long internode early spring growth after the growth settles down. Later growth usually has smaller internodes.
I have also noted that smaller shoots growing close to a strong one usually have really compact internodes so I often leave a strong sacrifice branch just above a branch I intend to keep. Prune the strong one later in the season when you have a good start on the keeper.

Thanks, I'll try that.