I prefer a glufosinate-based herbicide rather than roundup (glyphosate). One brand name is 'Rely' if you can find it. But there are others. It is a broad spectrum herbicide but, unlike roundup, it is not as systemic and will not kill the roots. It will kill what it touches, but if you accidentally hit a shoot or low leaf on your vine, it will only kill that leaf, not affect the rest of the vine.