Wonderful philosophy. The trumpet vine IMHO is not evil. The consequences of their nature can be evil - as your experiment aims to show, by demonstrating what (the little) can be done to counter evil. Perhaps, not all sociopaths are neither....(just do evil deeds).... The pivot of your piece is to keep it up close and personal and not push evil into a corner of its own making. There is will thrive and gather into a larger than nuclear blast...
Love how everybody can join to love trees (as friends). You grow us all with this post!