There's a plant that's popped up in the back of my flowerbeds and I wanted to see if anyone could ID it. It was there last year and died back with winter, and is now more vigorous than before. It has leaves like a redbud, but it's not growing like a tree, and the main stems are this kind of neat rick-rack pattern instead of just straight.

I'm just outside of Ft Worth, TX.

Link to pic: http://www.catlyke.net/?attachment_id=757

Closer stems view: http://www.catlyke.net/?attachment_id=758