Trying to Get Rid of Forsythia

How do I permanently get rid of forsythia? I've tried digging it, burning it, and weed killer. It still comes back.

There are probably a few gardeners out there wishing they could get their forsythia to flourish like yours. I would recommend cutting the plants to ground level. Do this continually for a season or two to kill the plant. Or cut it back and treat the new growth with a total vegetation or brush killer. Several applications will be needed. Whether using traditional or new environmentally friendly products read and follow label directions carefully so you do not damage any of the nearby plantings and you are able to use the area for your desired purposes. Unfortunately theses products can kill any green plants they touch. So use carefully. Try a sponge applicator to wipe the product on the leaves or protect nearby plants to reduce the risk of damage.