I haven’t found trumpet vines to stop growing for anything, or anywhere. I have them sprouting up in the middle of my lawn. Or garden. Or anywhere. Aside agent orange or napalm I can’t say I can see them stopping growing for anything.
One side of my yard has 4ft chain link against my neighbors 6ft stockade. Unless I keep the trumpet vines well watered with my above recipe of chemicals, they keep growing in there, and will destroy the fence. Prior to destroying everything g in that gap I had 4” diameter trumpet vines in there.
Well the hunt continues for us. Thank you. I honestly had never herd of them.
I will add, if you want death. Look to Copper Sulfate. Granular and can be put in water like a rock salt am let breakdown to spray. Or drill stumps and toss in a spoonful, water and nature takes it course. Does no soil activity in stump roots, but a vine it will stagnant the soil for a few weeks.