Well-weathered Phragmites mixed in with a patch of Japanese knotweed (background) along the Neponset River in Dorchester, MA. Dig that fancy collar!
There's a lot of digging and soil movement going on in this area right now. The increased disturbance will likely be a boon for these invaders, since they are very good at spreading by vegetative reproduction. Even the tiniest fragments of their rhizomes (underground stems) that get broken off can grow into whole new plants.