Setaria parviflora

4. Setaria parviflora (Poiret) Kerguélen (syn.: S. gracilis Humb., Bonpl. et Kunth) (S-Am.) – A rare and usually ephemeral alien, although sometimes very persistent. Formerly regularly introduced as a wool alien in the valley of river Vesdre, at least between 1887 and 1957. In the past decades much decreasing and nearly always associated with cereals (perhaps mostly introduced with birdseed nowadays). Setaria parviflora is now usually found in port-areas: near unloading quays, by motorways,… It was very locally naturalised in the port of Gent on both sides of the canal Gent-Terneuzen: it was at first detected on the left bank where a small colony persisted between 1975 and 1985 (Robbrecht & Jongepier 1986, Robbrecht & Jongepier 1989). In 2001 a large and obviously well established population of Setaria parviflora (ca. 50 m²) was discovered on the right bank of the canal, close to a power station (see Verloove 2002, Verloove 2006). This colony persisted ever since (confirmed in 2014) and apparently survived the severe and successive cold winters of 2008-2011. Moreover, a new very large population was discovered nearby in 2012: Setaria parviflora grows in abundance on the southern bank of the Moervaart at its junction with the canal Gent-Terneuzen. It was confirmed in relative abundance in Ardooie in 2007 where it persists as a pavement weed since at least 1997 (although now gone). In 2017 S. parviflora was also discovered on a canal bank in Genk, along with other xerophilous alien grasses such as Paspalum dilatatum and Sporobolus indicus.

Setaria parviflora is often very reminiscent of S. pumila and possibly overlooked. It is a perennial with a narrower inflorescence and smaller spikelets but otherwise much alike.

Herbarium specimen

Setaria parviflora, root - Drawing S.Bellanger

Setaria parviflora, Gent (port area), S-side of Moervaart (close to  canal Gent-Terneuzen), worked-up roadside, September 2012, F. Verloove Setaria parviflora, Gent (port area), S-side of Moervaart (close to  canal Gent-Terneuzen), worked-up roadside, September 2012, F. Verloove
Setaria parviflora, Gent (port area), S-side of Moervaart (close to  canal Gent-Terneuzen), worked-up roadside, September 2012, F. Verloove  

 


Selected literature:

Clement E.J. (1980) Adventive news 18. Mixed bag. BSBI News 26: 12-18.

Robbrecht E. & Jongepier J.-W. (1986) Floristische waarnemingen in de kanaalzone Gent-Terneuzen (België, Oost-Vlaanderen & Nederland, Zeeuws-Vlaanderen), vooral van 1981 tot 1985. Dumortiera 36: 6-21.

Robbrecht E. & Jongepier J.-W. (1989) De synantrope flora van het havengebied van Gent (België, Oost-Vlaanderen), waarnemingen van 1986 tot 1988. Dumortiera 44: 1-12.

Verloove F. (2002) Ingeburgerde plantensoorten in Vlaanderen. Mededeling van het Instituut voor Natuurbehoud n° 20: 227 p.

Verloove F. (2006) Setaria parviflora. In: Van Landuyt W., Hoste I., Vanhecke L., Van den Bremt P., Vercruysse W. & De Beer D., Atlas van de flora van Vlaanderen en het Brussels gewest. Instituut voor Natuur- en Bosonderzoek, Nationale Plantentuin van België en Flo.Wer: 826.

Verloove F. & Vandenberghe C. (1996) Nieuwe en interessante voederadventieven voor de Belgische flora, hoofdzakelijk in 1995. Dumortiera 66: 11-32.

Vivant J. (1960) Setaria geniculata (Lam.) Pal. (S. gracilis H.B.K.) naturalisé dans le sud-ouest de la France. Bull. Soc. Bot. Fr. 107: 29-31.

Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith