All bow to our alien overlords !!

[MaryN]

I am sure if the situation required it, you would devote resources to dealing with unwanted invaders. The two plants mentioned above may be regarded as a menace now, but could have potential for other uses once there is no need to keep waterways clear. Who knows. Situations change. Believe it or not, once plants are allowed to grow their own ways pests and diseases are often kept under control by the plants themselves. It is only the hybridisation of plants, and the growing methods of humans that have caused so many of the diseases and pests that now rampage across the countryside.