Oops! I got it wrong a few days ago. Here is a video link of the real culprit.
watch?v=xw1irzxDsXc&p=1E77798E361EAC3E&index=2&playnext=2
Looking it up online has made me realise what a lot of damage is being done in physical and economic terms. Wonder if the Himalayan Balsam will end up being the same?
The radio/photos video series explains that the government is considering introducing a predator.
Interesting, indeed. It is curious how “plants” in one region are “weeds” in another. I have planted a few Spanish Brooms (http://en.wikipedia.org/wiki/Spanish_Broom) here. They are pretty decorative plants planted by many in my area (+ 6000 ft. or 1,828.8 meters), but in some areas, where it is hotter than it is here, they spread like wildfire and are considered noxious (http://www.ncrcd.org/scotchbroom.html).
The “scotchbroom” covers several hillsides between here and Oban – and it seems to bloom for more than half the year. Frightening to see what plants can do in terms of colonisation.