Species Detail - Himalayan Knotweed (Persicaria wallichii) - Species information displayed is based on the dataset "Irish vascular plant data 1999-2009".
Terrestrial Map - 10km
Terrestrial Map - 10km
Distribution of the number of records recorded within each 10km grid square (ITM).Marine Map - 50km
Marine Map - 50km
Distribution of the number of records recorded within each 50km grid square (WGS84)._0.jpg)
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Persicaria wallichii
Himalayan Knotweed
NBNSYS0000003765
RecommendedWell-formed
Aconogonon polystachyum (Wall. ex Meisn.) M. Král, Aconogonum polystachyum (Wall. ex Meisn.) M.Král, Persicaria polystachya non Opiz (Wallich ex Meissner) Gross, Persicaria polystachya non Opiz (Wall. ex Meisn.) H. Gross, Pleuropteropyrum polystachyum (Wall. ex Meisn.) Javeid & Munshi, Polygonum polystachyum Wallich ex Meissner, Polygonum polystachyum Wall. ex Meisn., Reynoutria polystachyum Wall. ex Meissner, Rubrivena polystachya (Wall. ex Meisn.) M.Král, Rubrivena polystachya (Wall. ex Meisn.) M. Král
Invasive Species: EU Invasive Alien Species Regulation No. 1143/2014 || Invasive Species: Regulation S.I. 477/2011 (Ireland) || Invasive Species: Medium Risk Invasive Species (2013 Report) || Invasive Species: Regulation S.I. 374/2024 (Ireland) || Invasive Species: The Wildlife (Northern Ireland) Order 1985
pewal
Greuter & Burdet
Flowering plant
Species
1
1
1
21/08/2002
21/08/2002
22 March (recorded in 2014)
25 November (recorded in 2013)
Dr David Thomas Holyoak, Irish vascular plant data 1999-2009, National Biodiversity Data Centre, Ireland, Himalayan Knotweed (Persicaria wallichii), accessed 26 August 2025, <https://maps.biodiversityireland.ie/Dataset/35/Species/29165>