Reynoutria japonica

To be wanted is a contextual state
Relative to location, in our knotweed case
Ground up as a paste, the menace is on
Growth from anywhere makes hither yon
Pulled up may slow but the chemical stop
Won't get them gone while the pests may get got
Battle for sun and the rain and the food
That otherwise runs to the others
Intrusion confusion may justify harm
While yarns make a mockery 
Strengthening arms
Shorten the long and climb up the trees
Doing it quickly and quite as you please