Smoke Tree

Question

My question did not refer to pruning for a tree as opposed to a bush. We know how to do that. We need to know how to eliminate the growth (suckers?) at the base of one tree. The other tree does not have this problem.

Answer 1

Perhaps, this article on Tree Sucker Control will help: https://www.gardeningknowhow.com/ornamental/trees/tgen/tree-sucker-removal-and-tree-sucker-control.htm