In a small portion of my yard mustang grapes have established
themselves. Originally this happened on the other side of a fence
hidden from my sight by a passiflora vine on the fence itself.

Last year the grapevine engulfed the passiflora to the point that it
killed it, and did a fairly good job at engulfing a ~5 year old pecan
sapling. Over the winter I cut back all of the dead foliage and the
pecan tree is now thriving, but I don't want to replant along the fence
unless and until I can kill the currant.

Glyphosate herbicides don't seem to be making much of a permanent dent;
the vines continue to return although in somewhat sickly form. The
former owner buried enough broken concrete, in several hundred pound
slabs, that it would take earth moving equipment to root out the vines.
Should I simply continue regular applications of the glyphosate
herbicide and be patient?

What is the city using to control mustang grapes along the Town Lake
greenbelt, is it working, and is it available to non-professionals?

Any advice?

Thanks,
--
Mike Harris
Austin, TX