1. Cortaderia selloana (Schult. et Schult f.) Aschers. et Graebn. (syn.: C. argentea (Nees) Stapf, Arundo selloana Schult. et Schult. f., Gynerium argenteum Nees) (S-Am.) – A much-planted ornamental grass. Rather rarely seen as a relic of cultivation in abandoned gardens or occasionally as a garden throw-out. The first spontaneous appearance (self-sown) probably dates back to 2004: one young non-flowering specimen in a grassy slope of the central reservation of the R8-motorway around Kortrijk near Kuurne. Also observed in deforested coastal dunes (nature reserve Hannecartbos) in Oostduinkerke in 2006 (a single, self-sown specimen – not confirmed subsequently). In 2009 a single subspontaneous plant was seen on a demolition site in Izegem and on an off-ramp of a motorway (R1) in Antwerpen (near Berchem). In the latter locality seen for the first time in flower in 2011. In 2010 also recorded from the nature reserve Fluithoekduinen in Koksijde (a single specimen). From 2011 increasingly seen and obviously naturalising locally. A dense population of several tens of specimens was discovered on rough ground in Beveren (Roeselare).
Cortaderia selloana should be looked for in residential areas in the coastal sea dunes. It might be overlooked and non-flowering specimens might well be confused with large-leaved native grasses like Ammophila arenaria (L.) Link. However, it has a ligule of hairs (not membranous) and its leaf margins are sharply serrulate. A future naturalisation in this climatologically suitable area is very likely.
In more temperate regions in Europe, including southwestern France, Spain, etc., Cortaderia selloana is rapidly increasing recently and is often experienced as a noxious invader once established (see for instance Domènech & Vilà 2007). Additional information about its invasion in Europe is provided by DAISIE at: http://www.europe-aliens.org/pdf/Cortaderia_selloana.pdf.
Clement E.J. (2005a) Cortaderia selloana does self-sow abundantly in Britain. BSBI News 99: 47-48.
Domènech R. & Vilà M. (2007) Cortaderia selloana invasion across a Mediterranean coastal strip. Acta Oecologica 32(3): 255-261.