Fallopia japonica var. japonica - Japanese Knotweed
Japanese Knotweed is one of the most successful alien plants and is still extending its range in Cornwall. It has become a dominant species along many river corridors such as the White river near St. Austell (SX05C) and the Cot valley near St. Just (SW33Q). It is also common on waste ground, especially where soil has been moved around or brought onto the site, along road verges and banks, and sometimes on hedges and in woodland. Large scale earth movements resulting from Derelict Land Reclamation schemes have been particularly noticeable in establishing and spreading this highly invasive and pernicious species. Japanese Knotweed also occurs on the Isles of Scilly.
Click here to see Aphotoflora images by David Fenwick
Source:
French, C.N., Murphy, R.J. & Atkinson, M. 1999. Flora of Cornwall. Wheal Seton Press, Camborne.