For the most part I would say a heavy power rod, but again, power ratings can be pretty different. Considering rods in I've used in the past, a 4 power (heavy) Dobyns is what I would use for 1/2oz jigs, and some guys even like a 5 power in the Dobyns line for that. However, I would also be comfortable with a MH St. Croix Avid for 1/2oz jigs in rocks/wood.
Now saying that, personal preference on how you like your rod to load/handle the lure will play a big factor into your choice as well.