Jimmy Turner, director of research at the Dallas Arboretum & Botanical Society, is on a mission to stop mass murder. It kills him to see crape myrtles hacked, chopped and topped around North Texas.

MILTON HINNANT/DMN

Stop this: Don't top crape myrtles to control their height.

"I honestly don't know why people feel like they have to top their crape myrtles," Mr. Turner says with a sigh. "I guess people do it because their dad did it or their neighbor does it, but there's nothing that can be gained by this destructive process."

In fact, he says, you can weaken the tree and ruin its shape by beheading it.

Mr. Turner acted as consultant with the Crape Myrtle Trails of McKinney to create a pamphlet that lists the following guidelines for trimming your trees:

•Never use pruning as a means of height control. Transplant tall varieties to more spacious surroundings.

•Remove nothing (including seed heads) from the top of a large crape myrtle.

•Remove unwanted branches from the bottom of your crape myrtles in order to train them to grow tree-form.

•Remove damaged branches or those that rub against each other from the interior.

If your plant has been "crape murdered" by topping it, the quickest way to restore it is to cut the crape myrtle completely to the ground in late winter. Retrain the vigorous growth that comes back from the root system.

Lisa Martin is an Arlington freelance writer.