2. Persicaria nepalensis (Meissn.) H. Gross (syn.: Polygonum nepalensis Meissn.) - An exceptional, locally naturalized alien. Discovered in 2010 in relative abundance on sandy tracks in woodland in Averbode (see also: http://waarnemingen.be/soort/view/135488). Obviously present since quite some time already. Since 2013 also discovered in several localities in the surroundings of Brugge, mostly in cemeteries.
Persicaria nepalensis is increasingly recorded in neighbouring countries as well. Several recent German records were associated with birdseed (for gaming) (Diekjobst 1994, Aboling 2008, Schepers 2011). This most likely is the vector of introduction in Averbode as well.
In several parts of the world Persicaria nepalensis is increasingly reported as an invasive environmental weed, especially in the Americas (see for instance Meier 2006, Vibrans & Alipi 2008). For that reasons, its populations in Averbode are now monitored and controlled but its eradication does not seem successful so far.
A rather similar species, Persicaria runcinata (Buch.-Hamilt. ex D. Don) H. Gross (syn.: Polygonum runcinatum Buch.-Hamilt. ex D. Don), was recently recorded as an escape in the British Isles (Macpherson & Clement 2003). See under Persicaria capitata for more details.
|
|
 |
Selected literature:
Aboling S. (2008) Persicaria nepalensis (Meisn.) H. Gross – Erstnachweis für Niedersachsen. Flor. Rundbr. 41: 33-38.
Diekjobst H. (1994) Der Nepalesische Knöterich (Polygonum nepalense Meisn.), ein Neufund in Deutschland. Flor. Rundbr. 27(2): 90-93.
Kalveram T. (2015) Vorkommen des Nepal-Knöterichs, Persicaria nepalensis (MEISN.) H. GROSS, in der Haard (Haltern am See, Nordrhein-Westfalen). Online Veröff. Bochumer Bot. Ver. 7(2): 11-14. [available online at: http://www.botanik-bochum.de/publ/OVBBV7_2_Kalveram_Persicaria_nepalensis.pdf]
Kowalczyk T., Pliszko A. & Drobniak S.M. (2014) Persicaria nepalensis (Polygonaceae), a new potentially invasive anthropophyte in the Polish flora. Polish Botanical Journal 59(2): 255-261. [available online at: http://botany.pl/ibwyd/pol-b-j/pbj59.html]
Macpherson P. & Clement E.J. (2003) Persicaria runcinata in the Clyde Valley (V.C. 77). BSBI News 92: 44-45.
Meier W. (2006) Contribución al conocimiento de Persicaria nepalensis (Meisn.) H. Gross y P. capitata (Buch.-Ham. ex D. Don) H. Gross, especies invasoras en el Parque Nacional El Avila, Venezuela. Acta Bot. Venez. 29(1): 1-16.
Pignatti-Wikus E. (1973) Polygonum nepalense Meisn., avventizia nel Bellunese. Giorn. Bot. Ital. 107: 291-294.
Schepers G. (2011) Erstfund von Persicaria nepalensis (Meisn.) H. Gross im Rheinland. Decheniana 164: 95-97.
Tan K. & Baytop A. (1995) Polygonum nepalense Meisn. in Turkey. Turkish J. Bot. 19(6): 601-602.
Vibrans H. & Alipi A.M.H. (2008) Notes on neophytes: 4. Polygonum nepalense (Polygonaceae), an invasive plant new for Mexico. Acta Botanica Mexicana 82: 1-6.