Commelina communis and Atriplex oblongifolia: two alien plants spreading in the north-east of France (Alsace)
Commelina communis (Commelinaceae) is a small herbaceous plant with a blue corolla. It originates from Asia (Far East). It was first recorded in the 1960s in Alsace (France) and has lately been more and more often recorded as naturalized in different habitats: forest borders (Schirrhoffen), wastelands and gardens (Barr, Obernai) and on very urbanized places such as pavements (Strasbourg). However the plant is only considered as a “weed” or “naturalized” by the Global Compendium of Weeds, it is quoted as an invasive alien plant in Montenegro (Stevesic et al., pers. comm.) and in Lithuania (Lithuanian Invasive Species Database).
Atriplex oblongifolia (Chenopodiaceae) originates from a zone extending from Ukraine to Iran and is a chamephyte growing up to 1.5 m in eight. It is frequently found along roads. It is only known as “naturalized” by the Global Compendium of Weeds. It is recorded in Belgium and in Germany. In France, it recently proliferated in Alsace (Haut-Rhin) and is also known in the Rhône area (JM Tison, pers. comm.)
Sources
Danijela Stesevic and Danka Petrovic, Snezana Vuksanovic and Nada Bubanja, Urban area of Podgorica (capital), Babji zubb (central part) and Ulcinjska beac (southern part), personal communication, denist@cg.yu
The Global Compendium of Weeds: http://www.hear.org/gcw/alpha_select_gcw.htm
Lithuanian Invasive Species Database: http://www.ku.lt/lisd/species.html
Jean-Marc Tison, personal communication, jmt6@wanadoo.fr