pcollingridge's picture

Japanese Knotweed

Observed: 19th March 2011 By: pcollingridgepcollingridge’s reputation in Plantspcollingridge’s reputation in Plants
Japanese Knotweed
Showing emerging bud
Showing rhizome
Showing rhizome
Showing rhizome
Fallopia japonica

Has been growing beside a small pond for several years - last year the wardens sprayed it & overwinter cut it back.... but it just doesn't want to die!
The foliage & flowers were taken last year. The bare stems were taken in Feb this year

Species interactions

No interactions present.


leenestofvipers's picture


We used to call that Wild Rhubarb when we were kids and used to eat it.....does taste like rhubarb.

BDeed's picture


I think spray treatment will take at least 3 years, i really don't like this plant!! Highly invasive and almost impossible to get rid of, it'll spread from a tiny piece of plant material and suffocate everything in it grows over (although i have noticed in places bluebells seem to like growing under it!).

anonymous spotter's picture

Repeated applications of herbicide -

are needed to control it, and that can affect the surroundings, especially by a watercourse.
It can be dug out, but you have to go quite deep, and remove even the tiniest fragments of root. On a landfill it has to be buried at least 2 meters down to stop it re- growing there.
Whoever introduced it to the UK should - together with the one who did the same with Himalayan Balsam - be burnt in effigy instead of Guy Fawkes every year!