I'm leaning toward the arbor threats. They seem to work well on many trees. So nice to have figs, and not the reeds. They look like bamboo...is this a possibility? If so, blast away at them, as they will take over everything. I've heard of people building cement moats in the ground really deep, to control them. I yi yiiii....
it is Arundo dorax - looks a lot like bamboo but is not as strong. clumping bamboo is okay - the other one - watch out!!! good to make biochar with...
Yes, some of those, once you get them going, as you say, watch out. They're a forever thing.
Do you make biochar? I learned about it from @haphazard-hstead. A new one on me...