Do those bags that you buy to catch bagworms really work ?
Delaware County Ohio
I know of no method of controlling bag worms that involves a bag. Maybe you are thinking of the Japanese beetle traps that use a pheromone attractant to lure the Japanese beetle into a bag that they can't get out of (no longer a recommended method for control).
If you are really thinking of bag worms, then look at the two links below: If you have further questions, please ask.