Do any of you have large crape myrtles that you groom each year?

I let mine go once I trim it in the spring, but year after year I get a build up of stems and roots at the base of the plant that keep trying to generate more long stems. I like to keep them trimmed from the ground up to about 2 feet.

I am not sure what to do about the build up of stems that are around the plant. It is a wonderful place for ants, and pretty hard to control.

I have 16 crape myrtles, and would love to know what the rest of you do if you have this situation. (My neighbor just lets his go, and one is almost at the top of his two story house.) I want mine to stay at about 10 feet or so, not be giants.

Sammy