The last 8 days I have been out surveying in the northern half of Wales. Have visited all the sites for Impatiens noli-tangere (Touch-me-not Balsam). One site there must have been in the region of 100,000 plants. It grew here for well over 1km along a river and along woodland rides. Other sites were much smaller. Only one site couldn't be located, this was in Denbighshire. Another site in Merionethshire looks like it's bigger cousin Himalayan Balsam will soon swamp it out.