How do I prune for healthy, multiple trunks? I have a Turkish madrone (Arbutus andrachne) and a Chinese fringe tree (Chionanthus retusus) which can grow in this manner. Both are one gallon "sticks" at this point. I can top them to stimulate lower branches. Should I pick several buds from just above the crown? Can the sprouts all come from the same level or should they be from various locations within a foot or two of the ground surface? How do I select sprouts that will produce a structurally sound mature tree?
I have never heard of topping stimulating growth in other areas. You might contact the folks at a bonsai website to see if it's even possible to force a tree to become more bushy. I know that removing tops of trees encourages more grown, but on the top and this growth is poorly attached suckers which comes off in storms.