Is your poison ivy on the ground, or climbing. Mine is mainly climbing, and I find that if I cut it off at the base (I use a sharpened shovel) after a year or so it does give up. i have ivy on the ground--english ivy, and Im using cardboard on it. It is mainly propagated by birds who plant the seeds all over the place. So if you can get it under control before the seeds ripen you are ahead of the game. But if the birds plant more seeds, it will be back.
