Sisymbrium volgense Bieb. ex E. Fourn. (SW-Russia) – A very rare, locally naturalised alien. First discovered at the railway station of Quaregnon-Wasmuel in 1953 but not confirmed lately. Known since at least 1974 from a slope of an old mill in Oud-Turnhout (at least 1600 specimens in the 1970’s but by now much reduced; Verloove 2002). Finally also discovered on a talus of a railway track near the port of Gent in 1996 and subsequently further spreading in the surroundings on waste land.
Sisymbrium volgense is a rhizomatous perennial and thus forms dense stands. Curiously, ripe fruits are rarely (if at all) produced. It is a rather unshowy, Brassica-like plant that could easily pass unrecorded. Its perennial life-form, slightly glaucous foliage, tiny yellow flowers and often undeveloped fruits are diagnostic features.
Brennenstuhl G. (2016) Sisymbrium wolgense M. Bieb. ex E. Fourn. im Stadtgebiet von Salzwedel (Altmark). Florist. Rundbr. 50: 120-126.
Clement E.J. (1979) Sisymbrium volgense Bieb. ex E. Fourn. in Britain. Watsonia 12: 311-314.
Jehlík V. (1981) Chorology and ecology of Sisymbrium volgense in Czechoslovakia. Folia Geobot. Phytotax. 16(4): 407-421.
Oprea A. and Sîrbu C. (2010) Sisymbrium volgense (Brassicaceae) in the flora of Romania. Analele Universităţii din Oradea - Fascicula Biologie 27(2): 296-299. [Available online at: http://core.kmi.open.ac.uk/display/861901]
Shaw J.M.H. (1995) Sisymbrium volgense: new to Derbyshire. BSBI News 68: 43.
Verloove F. (2002) Ingeburgerde plantensoorten in Vlaanderen. Mededeling van het Instituut voor Natuurbehoud n° 20: 227 p.